Petioles absent or short, sometimes resembling a pulvinus. Unisexual flowers are common in Medusagyne and in Quiinoideae (except Froesia), but restricted to a clade of three genera in Ochnoideae. Unisexual flowers are found in Schuurmansia, Schuurmansiella, and Euthemis. The flowers are always unisexual in Schuurmansiella.
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The Chenopodioideae are annual or perennial herbs, subshrubs, shrub or small trees. The leaves are usually alternate and flat. The flowers are often unisexual. Many species are monoecious or have mixed inflorescences of bisexual and unisexual flowers.
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The unisexual salamanders (genus Ambystoma) are the oldest known unisexual vertebrate lineage, having arisen about 5 million years ago. In these polyploid unisexual females, an extra premeiotic endomitotic replication of the genome, doubles the number of chromosomes. As a result, the mature eggs that are produced subsequent to the two meiotic divisions have the same ploidy as the somatic cells of the adult female salamander. Synapsis and recombination during meiotic prophase I in these unisexual females is thought to ordinarily occur between identical sister chromosomes and occasionally between homologous chromosomes.
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Flowers are generally unisexual, and can range from tens of cm to over a meter large.
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Mole salamanders are an ancient (2.4–3.8 million year-old) unisexual vertebrate lineage. In the polyploid unisexual mole salamander females, a premeiotic endomitotic event doubles the number of chromosomes. As a result, the mature eggs produced subsequent to the two meiotic divisions have the same ploidy as the somatic cells of the female salamander. Synapsis and recombination during meiotic prophase I in these unisexual females is thought to ordinarily occur between identical sister chromosomes and occasionally between homologous chromosomes.
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All flowers are monoecious and unisexual, producing a spike inflorescence. All inflorescences are subtended by shorter, proximal bracts.
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Alternatively, if each individual plant has only unisexual flowers of the same sex then the species is "dioecious".
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The silvery salamander (Ambystoma platineum or LJJ) was once considered a distinct species of mole salamander from the United States of America and Canada. It is usually between 5.5 – 7.75 in (12 – 19.9 cm) long and is slender with many small silvery-blue spots on its back and sides. It is brownish grey and the area around its vent is grey. This unisexual Ambystoma hybrid species,Unisexual Salamander Complexes has been grouped with other unisexual ambystomatids that takes genetic material from Jefferson salamander (A.
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Members can be recognized as large marsh herbs with two-ranked leaves and a brownish compact spike of unisexual flowers.
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The entire plant is hairless (glabrous). The flowers are unisexual, carried on the same inflorescence (i.e. the plant is monoecious).
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Kleptogenesis is a sexually parasitic form of reproduction in unisexual organisms, that is often associated with species that are also capable of gynogenetic reproduction. In this reproductive mode unisexual females mate with sympatric males of related species, and genetic material in the paternal line recombines with the maternal DNA and thus is passed on. This mode of reproduction can be seen in numerous, though not all, species of unisexual salamander, particularly salamanders in the genus Ambystoma, and is implicated in the exceptional genetic diversity that exists in those animals.
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Inflorescences are unisexual, while its fruit is ovate, approximately x , with a very short apex, largely included in the pubescent perigon.
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The flowers unisexual. Its flowers have 3 sepals, 0.7-1 by 1-1.5 millimeters, that are partially fused at their base.
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Some genera and species have laurel forest foliage due to convergent evolution. Dodonaea viscosa flowers The flowers are small and unisexual, or functionally unisexual, though plants may be either dioecious or monoecious. They are usually found in cymes grouped in panicles. They most often have four or five petals and sepals (petals are absent in Dodonaea).
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Chionanthus polygamus is a tree in the family Oleaceae. The specific epithet polygamus refers to the tree having both unisexual and bisexual flowers.
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Similarly, Ambystoma laterale, Ambystoma jeffersonianum, Ambystoma texanum and Ambystoma tigrinum have been identified as extant parent species to unisexual salamanders within the same genus. However, mitochondrial evidence suggests that the origins of hybrid Ambystoma, on the maternal line, lie in a relative of Ambystoma barbouri. In spite of this, all extant unisexual species of Ambystoma share no nuclear DNA with Ambystoma barbouri.
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Melicope triphylla grows up as a shrub or tree up to tall. The flowers are unisexual. The ellipsoid to roundish fruits measure up to long.
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Dawley, RM & Goddard, KA. 1988. Diploid-triploid Mosaics among Unisexual Hybrids of the Minnows Phoxinus-Eos and Phoxinus- Neogaeus. Copeia, 3: 650-660.Kupritanova, L. 2009.
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In the majority of plant species, individual flowers have both functional carpels and stamens. Botanists describe these flowers as "perfect" or "bisexual", and the species as "hermaphroditic". In a minority of plant species, their flowers lack one or the other reproductive organ and are described as "imperfect" or "unisexual". If the individual plants of a species each have unisexual flowers of both sexes then the species is "monoecious".
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Caribbean islands species. These plants are functionally dioecious, flowers imperfectly unisexual. :Pereskia marcanoi Semideciduous forests on Hispaniola at elevations of about 500 m (1600 ft). :Pereskia portulacifolia Hispaniola.
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Anisophyllea species grow as shrubs or trees. The bark is smooth to flaky. The flowers are unisexual. The fruits are drupes (pitted) and are ellipsoid or pear-shaped.
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Dacryodes species grow as shrubs to medium-sized trees. Their bark is smooth to scaly with pale sapwood. Flowers are unisexual. The fruits feature a fleshy and thick pericarp.
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Blue-spotted salamanders are known to be associated with unisexual (all-female) populations of ancient origin. The unisexual females often look like blue-spotted salamanders but have hybrid genomes and require sperm from a co-occurring, related species to fertilize their eggs and initiate development. Usually the eggs then discard the sperm genome and develop asexually (i.e., gynogenesis, with premeiotic doubling); however, they may incorporate the genome from the sperm into the resulting offspring.
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G. underwoodi is a unisexual species, reproducing through parthenogenesis. Captive specimens have been recorded laying up to eleven eggs within four months, with between one and four eggs per clutch.
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The tihue bears bundles of small yellow unisexual or hermaphrodite flowers. The fruit is a greenish achene with seeds bearing feathery anemophilous filaments. The seed is dispersed by the wind (anemochory).
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Corals can be both gonochoristic (unisexual) and hermaphroditic, each of which can reproduce sexually and asexually. Reproduction also allows coral to settle in new areas. Reproduction is coordinated by chemical communication.
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Various aspects of floral morphology promote allogamy. In plants with bisexual flowers, the anthers and carpels may mature at different times, plants being protandrous (with the anthers maturing first) or protogynous (with the carpels mature first). Monoecious species, with unisexual flowers on the same plant, may produce male and female flowers at different times. Dioecy, the condition of having unisexual flowers on different plants, necessarily results in outcrossing, and might thus be thought to have evolved for this purpose.
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In sequential hermaphrodites, where individuals function as one sex early in life and then switch to the other, the allocation decisions lie in what sex to be first and when to change sex. Animals may be dioecious or sequential hermaphrodites. Sex allocation theory has also been applied to plants, which can be dioecious, simultaneous hermaphrodites, have unisexual plants and hermaphroditic plants in the same population, or have unisexual flowers and hermaphroditic flowers on the same plant.
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The species is a climbing wintergreen plant. It has few or no thorns. The width to length ratio of its leaves is about 0.6. The flowers are unisexual, in a simple umbel.
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The species is a climbing wintergreen plant. It has few or no thorns. Its leaves are ovate or cordate, almost as broad as long. The flowers are unisexual, in a simple umbel.
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Male and female flower on different plants. The pollination is done by bees and other insects. The flowers are irregular. The flowers are unisexual, male flowers with 5 to 20 fertile stamens.
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A fire destroys the plant but the seeds survive. The seed is stored in a cap and spread by the wind. The plant is unisexual. Pollination occurs through the action of birds.
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Didymeles species are evergreen trees. The simple leaves are leathery in texture, with untoothed (entire) margins. There are no stipules. The flowers are unisexual, with the two kinds borne on separate plants (i.e.
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Nestegis species are evergreen trees or shrubs. The leaves are opposite, simple, entire, and coriaceous. The inflorescence is axillary, decussate, sometimes terminal and somewhat paniculate. The flowers are either bisexual or functionally unisexual.
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The six species of Ripogonum are perennials, either vines or shrubs. The leaves, which may have several different arrangements, lack stipules. The stems may have prickles. The Australian species are bisexual; others are unisexual.
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These plants are dioecious, i.e. unisexual, with male and female flowers on separate plants. There are 3 to 8 fused sepals, but no petals. The male flowers have 2 to 8 stamens, but no pistils.
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There are usually one to three leaves. The petiole sheath is short. Inflorescences are typical aroids with a spathe and spadix. It has no sterile appendix and its flowers, usually one to three, are unisexual.
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2014 Jul 29;5(4):e01494-14. doi: 10.1128/mBio.01494-14. PMID: 25073643 VGII C. gattii have probably undergone either bisexual or unisexual reproduction in multiple different locales, thus giving rise to novel virulent phenotypes.
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Polyploidy, a numerical change in the number of chromosomes, is common in parthenogenic amphibians. Triploidy (having three sets of chromosomes), tetraploidy (four sets of chromosomes) and pentaploidy (five sets of chromosomes) are common in salamanders. In unisexual salamanders these different levels of polyploidy are a result of multiple hybridization events, involving two to four species. Ambystoma nothagenes is a unisexual, triploid hybrid of Ambystoma laterale, Ambystoma texanum and Ambystoma tigrinum, while hybrids of Ambystoma platineum and Ambystoma texanum have been found to be tetraploid.
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The flowers are unisexual. Its flowers have 3 oval sepals, 1-1.5 by 1-1.5 millimeters. The sepals are smooth on their upper surface, hairy on their lower surface, and have fine hairs on their margins.
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It is a resinous tree, up to tall. Grayish bark is smooth in texture. Leaves are simple and alternately arranged, peltate, orbicular-ovate, apex is acuminate, and palmately 8 to 9-nerved. Unisexual flowers are dioecious.
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In the wild, five species of Ambystoma salamanders contribute to a unisexual complex that reproduces via a combination of gynogenesis and kleptogenesis: A. tigrinum, A. barbouri, A. texanum, A. jeffersonium, and A. laterale. Over twenty genomic combinations have been found in nature, ranging from "LLJ" individuals (two A. laterale and an A. jeffersonium genome) to "LJTi" individuals (an A. laterale, A. jeffersonium, and an A. tigrinum genome). Every combination, however, contains the genetic information from the A. laterale species, and analysis of mitochondrial DNA has indicated that these unisexual species most likely diverged from an A. barbouri individual some 5 million years ago, making them the oldest unisexual vertebrate species on Earth The fact that these salamanders have persisted for so long is remarkable, as it contradicts the notion that a majority of asexual lineages arise when the conditions are right and quickly disappear. It has been argued that this persistence is very much due to the aforementioned "genome replacement" strategy that accompanies kleptogenic reproduction—replacing a portion of the maternal genome with paternal DNA in offspring has allowed unisexual individuals to "refresh" their genetic material through time.
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The shrub is round and grows high and blooms from September to January. Fire destroys the plant but the seeds survive. The seed is stored in a cap and spread by the wind. The plant is unisexual.
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The inflorescence is multibranched and from 200 to 400 mm long. The tightly packed flowers are unisexual and coloured lilac to pink. Male flowers are borne in pairs, and have six stamens. The female flowers are solitary.
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Flowers are pentamerous, white and solitary in auxiliary spikes. M. glauca is usually hermaphroditic or sometimes unisexual by abortion of pollen or ovules. The corolla tube is short with spreading lobes. Flowering occurs in January and February.
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Species names were later dropped for all unisexual salamanders because of the complexity of their genomes. The offspring of a single mother may have different genome complements; for example, a single egg mass may have both LLJJ and LJJ larvae. Despite the complexity of the nuclear genome, all unisexuals form a monophyletic group based on their mitochondrial DNA. The maternal ancestor of the unisexual ambystomatids was most closely related to the streamside salamander, with the original hybridization likely occurring 2.4-3.9 million years ago, making it the oldest known lineage of all-female vertebrates.
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A list of the known unisexual vertebrates, pp. 19-23 in: Evolution and Ecology of Unisexual Vertebrates. R.M. Dawley and J.P. Bogart (eds.) Bulletin 466, New York State Museum, Albany, New York Other usually sexual species may occasionally reproduce parthenogenetically; the Komodo dragon and hammerhead and blacktip sharks are recent additions to the known list of spontaneous parthenogenetic vertebrates. As with all types of asexual reproduction, there are both costs (low genetic diversity and therefore susceptibility to adverse mutations that might occur) and benefits (reproduction without the need for a male) associated with parthenogenesis.
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The plants are upright, unbranched and unisexual. Their stems are naked, up to 3 cm high, are shiny and have large leaves. Male plants have large, rose-like clusters of leaves at the tip. Female plants have capsules.
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Amaranthus graecizans is an annual herb that grows up to tall. Stems are branched from base, glabrous or covered with crisped hairs. The flowers are unisexual and are yellow with round black seeds that are 1–1.25 mm.
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The entire animal, including tentacles, is several meters long. The feeding polyps are pink when young, before developing tentacles. A mature feeding polyp is yellow with a single tentacle. Colonies are unisexual, and reproduce by incomplete asexual reproduction.
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Poeciliopsis monacha—occidentalis is a unisexual (all female) hybridogenic lineage. It is an ancient clonal lineage that appears to be more than 100,000 generations old. The maternal ancestor was P. monacha and the paternal ancestor was P. occidentalis.
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The tree grows up to tall. It has deciduous pinnate leaves 10–20 centimeters (4–8 inches) long. The plants are dioecious, with separate male and female trees. The flowers are apetalous and unisexual and borne in panicles.
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"Scientists discover unknown lizard species at lunch buffet" (CNN, November 10, 2010). This species is one of four unisexual Leiolepis agamospecies. However, the genus Leiolepis has five different bisexual species. This unisexuality is possibly due to mutation and hybridization.
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They are arranged alternately and have stalks (petioles). The ocrea is tubular and membranous. The inflorescences are terminal, paniclelike or racemelike, borne on stems (pedunculate). Individual flowers are either bisexual or unisexual, with four greenish to reddish brown tepals.
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The plant dies after a fire but the seeds survive. The seeds are stored in a cap and released after they are ripe and spread by the wind. The plant is unisexual. Pollination occurs through the action of birds.
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The sperm is absorbed through pores in the skin, causing fertilisation. Corals can be both gonochoristic (unisexual) and hermaphroditic, each of which can reproduce sexually and asexually. Reproduction also allows corals to settle new areas. Corals predominantly reproduce sexually.
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Venation of the leaves may be palmate to reticulate. A pair of tendrils often appear near the base of the petiole. The inflorescence type for members of this family is an umbel. The flowers are inconspicuous, radial and unisexual.
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Sometimes the bracts are absent and only their remaining tooth-shaped, awl-like, spatula-shaped or band-shaped appendages are recognizable. Dorstenia urceolata from Brazil. The globular, tapered, or warty flowers are unisexual. The female flowers within the receptacle mature first.
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The plants are large and showy, usually between high. They have wide-spreading, glistening leaves when moist that become shrivelled and dull when dry. The fertile plants are unisexual. The male plants can be distinguished by their conspicuously flattened heads.
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The seed is released one to two years after flowers are formed and spread through the wind. The plant is unisexual. Pollination may occur through the action of mammals. The plant grows in shale and sandy soil at altitudes of .
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K. borckiana is apparently a rare unisexual clone that reproduces through parthenogenesis, in that only 100 female museum specimens are known to exist and no male specimens. It is believed to have arisen from hybridization between Kentropyx calcarata and Kentropyx striata.
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Aphananthe is a small genus of evergreen trees in the family Cannabaceae. Around six species are recognised, found in Madagascar, South-east Asia, Mexico and Australia. Leaves are alternate on the stem and toothed. Flowers are unisexual, fruit form as drupes.
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The seed is stored in a cap, released after a long period and spread through the wind. The plant is unisexual. Pollination occurs through the action of rodents. The plant grows on sandstone soil on rock moldings at heights of 1.750 - 1900 m.
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Keep at some 20 °C to 20 °C. Germination will start after some 4 to 6 weeks. Keep seedlings cooler, yet frostfree with reduced watering in winter in a sunny spot. The flower is small, unisexual, yellowish-white, and arranged in axillary crests.
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The inflorescences are pyramidal panicles clad in yellowish hairs, up to long, growing in the leaf axils. The yellowish-green flowers are unisexual and regular with parts in fours. They are followed by single-seeded drupes, long, which are black when ripe.
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This is a deciduous tree with a straight, gray trunk that can measure up to 30 metres tall. Its leaves are ovate, ovate-cordate or lanceolate in shape, with conspicuous primary veins and serrated edges. The greenish flowers are unisexual and inconspicuous.
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Denver: Colorado Division of Wildlife. vii + 131 pp.Cole, Charles J.; Painter, Charles W.; Dessauer, Herbert C.; Taylor, Harry L. (2007). "Hybridization Between the Endangered Unisexual Gray-Checkered Whiptail Lizard (Aspidoscelis dixoni) and the Bisexual Western Whiptail Lizard (Aspidoscelis tigris) in Southwestern New Mexico".
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Urticating (stinging) hairs are often present. They have usually unisexual flowers and can be both monoecious or dioecious. They are wind-pollinated. Most disperse their pollen when the stamens are mature and their filaments straighten explosively, a peculiar and conspicuously specialised mechanism.
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Evidence on the molecular level has demonstrated this despite obvious morphological differences between the two families such as Barbeya having small, unisexual, petalless flowers, while the flowers of Dirachmaceae are characterized by their bisexuality, and their relatively large petals (and size in general).
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Flowers are unisexual and plants are dioecious (pistillate and staminate flowers are borne on separate plants). Stamen number ranges from four to several hundred. Shape and size of stamens are extremely variable. Sterile stamens are often present, both in pistillate and staminate flowers.
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Flowers are usually unisexual, rarely bisexual, with a cup-shaped calyx. Fruits are one or two-seeded. Chisocheton habitats are rain forests, typically understorey trees, from sea-level to about altitude. The wood of several Chisocheton species is used locally in light construction.
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The flowers are unisexual and found in axillary cymes at each leaf node. They lack petals and are generally on a stalk. The fruit is a capsules with three valves and produces tiny, oblong, four-sided red seeds. It has a white or brown taproot.
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The sterile stems are arched, like those of strawberries. Badge moss is the largest mnium. It can be distinguished from magnificent moss by its unisexual plants, leaf edges that extend down the stems for a noticeable length, and 3-6 stalked capsules per plant.
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A pair of trees in Kolkata. Alongside on the ground is a freshly shed leaf with the sheath still green. shedding of leaf in Royal palm Roystonea regia produces unisexual flowers that are pollinated by animals. European honey bees and bats are reported pollinators.
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Ambystoma platineum, a unisexual mole salamander species, are a result of the hybridization of sexually reproducing Ambystoma jeffersonianum and A laterale. A. platineum individuals normally live in proximity to either of these parent species, due to their need to use their sperm to facilitate reproduction.
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The inflorescence is a dense terminal cluster of many five-lobed pink flowers. Plants may have bisexual or unisexual flowers, with some plants bearing only male or only female flowers. The fruit is a shiny brown rounded achene around 3 millimeters (0.12 inches) long.
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The Board of Trustees of the Royal Botanic Gardens, Kew.Forzza, R. C. 2010. Lista de espécies Flora do Brasil . Jardim Botânico do Rio de Janeiro, Rio de Janeiro Dracontium species can be distinguished from related genera by their inflorescence, which is smaller and unisexual.
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The visible body is globose. The flowers are about 20 cm across, dioecious and unisexual. They have 10 bracts and are bright red in colour covered with sulphur-yellow spots. They appear above the ground, bloom for 2–3 days and have a putrid odour.
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Unlike most crown-shafted species, the inflorescence in R. melanochaetes emerges from the leaf axil rather than beneath the shaft. The much-branched panicle is 1–2 m with unisexual flowers of both sexes. Fruit matures to a 1 cm red drupe with one seed.
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It grows to be tall. The main stem does not have leaves but rather small scales (see phyllanthoid branching) and the secondary stems contain the flowers and leaves. The flowers are inconspicuous, small, and unisexual. Male and female flowers are located on the same plant.
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The flower are solitary in panicles. Some species have cleistogamous flowers produced after or before the production of typical flowers with petals. Flowers are bisexual or unisexual (e.g. Melicytus), actinomorphic but typically zygomorphic with a calyx of five sepals that are persistent after flowering.
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Alnus serrulata has unisexual flowers and is monoecious. Shown here: maturing male flower catkins on the right, last year's female catkins on the left. Ilex aquifolium is dioecious: (above) shoot with flowers from male plant; (top right) male flower enlarged, showing stamens with pollen and reduced, sterile stigma; (below) shoot with flowers from female plant; (lower right) female flower enlarged, showing stigma and reduced, sterile stamens (staminodes) with no pollen A "perfect" flower has both stamens and carpels, and may be described as "bisexual" or "hermaphroditic". A "unisexual" flower is one in which either the stamens or the carpels are missing, vestigial or otherwise non-functional.
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Leaves are exstipulate alternate simple palmately lobed or palmately compound. The flowers are unisexual, with male and female flowers on different plants (dioecious) or on the same plant (monoecious). The female flowers have inferior ovaries. The fruit is often a kind of modified berry called a pepo.
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Schaefferia is a genus of flowering shrubs and small trees in the family Celastraceae. The generic name honours German mycologist and clergyman Jacob Christian Schäffer (1718–1790). Members of the genus are found in the Neotropics. The plants are dioecious, with flowers that are unisexual by abortion.
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Each flower is on a densely hairy pedicel 4-9 millimeters in length. The flowers unisexual. Its flowers have 3 sepals, 2-3 by 1.5-3 millimeters. The sepals are smooth on their upper surface, hairy on their lower surface, and have fine hairs on their margins.
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The inflorescence is interfoliar and once branched, covered in brown hair, with unisexual flowers of both sexes. The female flowers are twice as big as the male's, both with three sepals and three petals. The fruit is globose to ellipsoidal, pink to red, with one seed.
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The leaf and leaflet stalks and axis may be brown and scurfy, while the leaf base is swollen and may be concave adaxially. The family members tend to be without stipules. The determinate, axillary inflorescences carry small, radial, unisexual flowers. The plants tend to be dioecious.
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Species placed in the genus Reynoutria are robust erect perennial plants, growing from rhizomes. They are usually monoecious, with mostly bisexual flowers, but also some unisexual flowers. The petals of the flowers are dry and paperlike when mature. The fruits are achenes with threefold sharp edges.
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The species was dioicous (unisexual), since it produced male and female gametes on separate gametophytes. Horneophyton grew on sandy, organic-rich soil in damp to wet locations. They usually grew as isolated individuals. Surface view of a polished piece of Rhynie chert showing many corms/tubers of Horneophyton.
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The flowers are unisexual, small, discreet green, thick as pea fruit, then changing to reddish blue. In colder areas the leaves in May check and fall in November. Though dioecious, in some communities males dominate the female specimens in number. It grows in oak woodlands and oak sclerophyllus.
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Individual plants are either male producing microspores or female producing megaspores. This plant being unisexual allows it to cross-fertilize with other screwpines. The male plants produce fragrant colorful flowers in long spikes. These long spikes are with 8–12 stamens inserted pseudo-umbellately on slender columns long.
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2009 Most genus members are dioecious, producing unisexual male or female flowers on separate plants. Ascarina lucida, the only member of its genus to occur in New Zealand, is monoecious.Lucy B. Moore. 1977 It will grow to a height of 6m and can have a 30 cm trunk.
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Scleria amazonica is a perennial herb spreading by means of underground rhizomes. Stem is triangular in cross-section, up to 120 cm tall. Leaves are up to 45 cm long, with a V-shaped ligule of dense hairs. Inflorescences unisexual, in a paniculate arrangement, up to 46 cm long.
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Within their range, Palaquium species are mostly found in the Philippines and Borneo. In Borneo many species are recorded in the Malaysian states of Sabah and Sarawak. The leaves are typically spirally arranged and often clustered near twig ends. Flowers are mostly bisexual, though some unisexual instances are known.
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Inflorescences are unisexual, sometimes bisexual, or globose, and borne in the leaf axils or on the older wood and branches. Pistillate (female) flowers line the outer surface of a large receptacle (‘bread fruit’). The flowering period is from October until February. The fruit is big, round, and greenish yellow.
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Heritiera javanica is a species of tree in the family Malvaceae, subfamily Sterculioideae. Like other species in this subfamily, flowers are unisexual; trees may grows up to 40 m high, and their Vietnamese name (under H. cochinchinensis) is huỷnh. No subspecies are listed in the Catalogue of Life.
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Spathe is leathery, 10–13 cm long with an ovoid tube which is green. Spadix is around 3.5 cm long, clavate and creamy white with the flowers unisexual and congested, female at base, male at tip, separated by sterile flowers in the middle. Fruits a cluster of berries.
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The inflorescence is usually compound with whorls of branches, though some are umbel-like, and others have solitary flowers. The flowers are regular, bisexual or unisexual. There are three sepals which usually persist in the fruit. Three petals, usually conspicuous, white, pink, purple, occasionally with yellow or purple spots.
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Ochnaceae is divided into three subfamilies: Medusagynoideae, Quiinoideae, and Ochnoideae. A molecular phylogenetic study resolved Medusagynoideae and Quiinoideae as sister subfamilies, but this result had only weak statistical support. In both subfamilies, the flowers are polystemonous. Except for the genus Froesia, many or all of the flowers are unisexual.
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Coprosma rhamnoides (also known as twiggy coprosma or red-currant coprosma) is an endemic shrub in New Zealand. It forms a small shrub up to 2 m tall. The leaves are very small, simple and variable in shape. The inconspicuous flowers are unisexual and believed to be wind pollinated.
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Croton pottsii is a perennial forb with ovate to elliptic shaped leaves, which are dusty green in color due to the presence of stellate hairs. The flowers can be unisexual or bisexual and lack petals. The species is named for John Potts, manager of the Chihuahua Mint.Seemann, Berthold.
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The circumscription of Dioscoreaceae has expanded over the years. For instance when Stenomeridaceae, as Stenomeris was also included in Dioscoreaceae as subfamily Stenomeridoideae together with Avetra, the remaining four genera were grouped in subfamily Dioscoreoideae, the two being distinguished by the presence of bisexual and unisexual flowers respectively.
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The leaves come to a tapering point at their tip. The leaves have 3-4 pairs of secondary veins emanating from their midribs. Its inflorescences are axillary and arranged as modestly branching, rigid panicles that are 12 centimeters long and covered in very small, fine hairs. Its flowers are unisexual.
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Excoecaria oppositifolia, an understory and evergreen tree species, belongs to the genus Excoecaria of the family Euphorbiaceae. It is found in Western Ghats of India and Sri Lanka. Trees are tall and leaves are simple and decussate in nature. Unisexual flowers are dioecious and inflorescence depends on the type of flower.
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The genus was first described by Carl Linnaeus in 1753. Within the family Polygonaceae, it is placed in the subfamily Polygonoideae. The genus Emex was separated from Rumex by Francisco Campderá in 1819 on the basis that it was polygamous (i.e. had both bisexual and unisexual flowers on the same plant).
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Flowering occurs from August to January, with flowers of a greenish coloration. The flowers are sub-sessile, and unisexual, with male and female flowers occurring on separate plants. Flowers are often solitary and are terminal on short branchlets. Male flowers have a cup-shaped calyx and a funnel-shaped corolla.
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The European beech (Fagus sylvatica) is the most commonly cultivated. Beeches are monoecious, bearing both male and female flowers on the same plant. The small flowers are unisexual, the female flowers borne in pairs, the male flowers wind-pollinating catkins. They are produced in spring shortly after the new leaves appear.
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Flowers are bisexual but sometimes also unisexual and pistillate. Flowers are hypogynous, have 5 sepals that are distinct and green in color and lanceolate to ovate in shape and 2.5-4.5 mm long. Typically with no stipules. The flowers have 5 petals that are white to soft pink in color and are clawed.
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It is a small, compact, soft-wooded, dwarf shrub with Unisexual flowers(dioecious). Its blue-green leaves are semi- evergreen. Its tiny compact branches spread, and often droop, staying close to the ground. It also develops a thick caudex or root-stock, which has led to it being a popular bonsai specimen.
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Maireana pyramidata is a low, dense, stiffly branched shrub of a height from 0.3 to 1.5 m, with finely woolly branches. It is both dioecious and unisexual. The leaves are alternate, narrowly cylindrical and covered with a mixture of dendritic (tree-like structure) and simple hairs. It fruits from August to November.
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Lamina is about 6-18 x 3.5-7.5 cm in length, shape is oblong to elliptic-oblong. Flowers are unisexual and dioecious. Inflorescence of Male flowers show axillary clusters on very short tubercles, silky tomentose; and female flowers are sessile, in axillary clusters. Fruits are as berries and usually bear 4 seeds.
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Kadsura japonica is a cultivated, dioecious, ornamental plant in gardens, and also has edible fruits that can be eaten raw or cooked. It grows from to . It is an evergreen with deep green, glossy leaves that turn slightly red in autumn. Its fruits are very bright scarlet and it has white, unisexual flowers.pfaf.
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Flowers appear before the leaves 1.5–2 cm across, in axillary panicles. Flowers are unisexual with both sexes being found on the same tree. They have no petals, but the calyx is coloured and functions as a corolla. In the male flowers the numerous anthers are fused together to form a column.
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The new borne twigs have little hairs. Male flowers have a unique verticil with 6–10 stamens and are surrounded by tepals (sepals and petals just the same). Female flowers are grouped five by five, and pollination is mainly anemophilous. The flowers are homochlamyd, small (3 to 5 mm), unisexual, arranged in inflorescences.
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Aextoxicon punctatum is a large tree often found in the canopy or emergent. It has opposite leaves with dark green coloration on the top and lighter green below, and is covered in rusty peltate scales. The flowers are actinomorphic and unisexual, in hanging racemes. The flowers have 5 sepals and 5 petals.
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Leaves are alternate, two-ranked, simple, pinnately veined, and have leaf stalks. Stipules absent. ; Flowers: Flower stalks are axillary to (on the opposite side of shoot from) leaf scars on old wood and sometimes from leaves on new shoots. The flowers are usually trimerous; borne singly or in compound inflorescences; bisexual and rarely unisexual.
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Parthenogenesis is a form of reproduction where eggs develop without fertilization, resulting in unisexual species. This phenomenon is closely related with reproductive modes such as hybridogenesis, where fertilization occurs, but the paternal DNA is not passed on. Among amphibians, it is seen in numerous frog and salamander species, but has not been recorded in caecilians.
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The laurel is dioecious (unisexual), with male and female flowers on separate plants. Each flower is fragrant creamy white flower, about 1 cm diameter, and they are born in pairs beside a leaf. The canary laurel is a vigorous, conical tree. Laurus novocanariensis is a species characteristic of laurel forest named laurisilva in Canary islands.
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The flowers are hermaphroditic or unisexual; in the latter case, the male and female flowers show differences associated with the timing of pollination. They are very small (1 or 2 mm), with four yellow-green tepals and four stamens. Flowering period extends from March to June. The fruits are small, red, fleshy drupes, in diameter.
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Flowering time is October–November. Flowers axillary, unisexual and vary in both arrangement and appearance. Male flowers are yellow and are arranged in a 3-flower cluster up to 3 cm long. Central flowers are longer than the laterals with their pedicel being 1–1.3 cm long versus the lateral length of 5–6 mm.
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Unlike its congeners, G. tinctoria and G. manicata, the leaves are small, approximately 6 cm across. They are rounded or kidney-shaped, stipulate on long (2–10 cm) petioles, with crenate edges. Flowers are unisexual, with female inflorescences shorter than male ones. The fruit is a bright red berry (drupe) 3–5 mm in diameter.
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In Ochnoideae, unisexual flowers are limited to a clade consisting of Schuurmansia, Schuurmansiella, and Euthemis. In Medusagyne and Quiinoideae, as in most angiosperms, the anthers open by longitudinal slits. In Ochnoideeae, the anther dehiscence is ancestrally poricidal, with several reversions to longitudinal slits. Testulea, Philacra, and Luxemburgia have anthers that open by apical pores.
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It consists of very fleshy flowers that are unisexual, which is exceptional for orchids. The colorful male and yellowish-green female flowers are typically situated on different plants. Which type of flower a plant produces is determined by the conditions under which it grows. Male and female flowers are markedly different in size and color.
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Ferula tingitana, the giant Tangier fennel, is a species of the Apiaceae genus Ferula. Despite the name, the plant is not a type of fennel proper, which belongs to another genus (Foeniculum). Ferula tingitana is a tall perennial herb. It has alternate leaf arrangement and yellow, unisexual flowers which, like other Apiaceae, grow in umbels.
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Rumex skottsbergii can be identified through their green, narrow, compact inflorescences, erect nature and small leaves. Their stems are usually stiffly erect with 7-10dm long and glabrous. Rumex skottsbergii can also be identified through their unisexual flowers and medium-sized yellowish greenish branched inflorescences; their outer tepals are also a distinguishable trait found within this genus.
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Typha are aquatic or semi-aquatic, rhizomatous, herbaceous perennial plants. The leaves are glabrous (hairless), linear, alternate and mostly basal on a simple, jointless stem that bears the flowering spikes. The plants are monoecious, with unisexual flowers that develop in dense racemes. The numerous male flowers form a narrow spike at the top of the vertical stem.
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Hakea epiglottis is a shrub commonly known as beaked hakea or needlebush hakea and is endemic to Tasmania where populations consist of functional unisexual plants. In a 1989 publication by John Wrigley & Murray Fagg states specimens at Wakehurst Place, an annexe of Kew Gardens London are specimens believed to be 60-70 years old measuring high and wide.
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The young leaves are covered in rust- coloured hairs, which distinguishes this species from the similar Hakea megadenia. Unisexual populations have male plants which do not produce fruit but flowers that produce pollen. Female populations have fruit with no pollen. There are recorded populations of bisexual plants where the fruit occur together with flowers producing pollen.
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The family is a group of evergreen or deciduous trees and shrubs with mucilaginous substances in leaf and bark tissue. Leaves are usually alternate on the stems. The leaf blades are simple (not compound), with entire (smooth) or variously toothed margins, and often have an asymmetrical base. The flowers are small and either bisexual or unisexual.
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Salamanders are the oldest known parthenogenic vertebrates. Molecular methods date the origins of unisexual salamanders to the Pliocene, from between 3.9 million to approximately 5 million years ago. All known parthenogenic amphibians have been the result of hybridization events between closely related species. Pelophylax esculentus, the edible frog, is the product of crosses between Pelophylax lessonae and Pelophylax ridibundus.
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Lamina parts of the leaves are x , narrow oblanceolate to elliptic, apex acuminate, base attenuate-cuneate to obtuse, margin subentire or crenulate, coriaceous, with glandular stinging hairs; midrib raised above; secondary_nerves 8-11 pairs; tertiary nerves distantly obliquely percurrent. Flowers with inflorescence axillary panicles, drooping, to long. Flowers are unisexual, subsessile. Fruit and seed are achenes.
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Its leaves are oval shaped or lanceolate and are generally long and wide, with a leaf stalk up to 18 mm. It has unisexual inflorescences, or clustered flowers. The fruit of Cucumis altheoides are spherical, in diameter, and are a pale green with darker green linear markings. At maturity the fruit turns more red, with 9 to 25 seeds.
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For example, a sporophyte that produces spores that give rise only to male gametophytes may be described as "male", even though the sporophyte itself is asexual, producing only spores. Similarly, flowers produced by the sporophyte may be described as "unisexual" or "bisexual", meaning that they give rise to either one sex of gametophyte or both sexes of gametophyte.
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The colour of the sepals and petals is highly diverse, it may be solid, or variable, or mutable. These may be of several colours, or solid, the striking combinations are of all colours except blue. There is no unisexual flowers in the species. Different species may be growing together, their massed displays creating painterly contrasts in flowering landscapes.
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Sterculia balanghas is a species of plant in the family Malvaceae. It is native to India and Sri Lanka. Leaves are simple, alternate; swollen at base and tipped; lamina elliptic, obovate, oblong, elliptic-ovate or oblong-ovate; base subcordate or round; apex acuminate; with entire margin. Flowers may be unisexual or polygamous are yellow or greenish-purple in color.
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Flowers are unisexual; male catkins are greenish-yellow forming spreading or pendulous clusters at the tips of the branches; female are axillary, solitary or in groups of 2–3. Acorns are narrowly obovate or subcylindrical, usually tapering towards base, 2–2.5 cm long and 0.8–1.2 cm wide, with a woody endocarp and cupule with strongly recurved scales.
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Comptonia peregrina is a deciduous shrub, growing to tall. The leaves of the plant are linear to lanceolate, long and broad, with a lobed margin; they give off a sweet odor, especially when crushed. Plants are monoecious with separate unisexual flowers. The staminate flowers grow in clusters at the ends of branches, and are up to long.
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Among the distinguishing characters of the genus are two series of stamens totaling twice the number of petals; free or nearly free petals (not joined in a tube); a stout rhizome from whose axils the flowering stems rise; and a basal rosette of leaves. This genus contains the only species of Crassulaceae that have unisexual flowers.
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Adenia cissampeloides is a woody vine that can reach up to in length. The stems are pale green to gray green and can be spotted. The leaves have smooth edges and are punctate (marked with dots), with a cordate (heart-shaped) to truncate (square) base. A. cissampeloides is monecious: it has unisexual flowers that occur in inflorescences.
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Flower of silver cockscomb, Celosia argentea, in Tirunelveli, India The flowers are solitary or aggregated in cymes, spikes, or panicles and typically perfect (bisexual) and actinomorphic. Some species have unisexual flowers. Bracts and bracteoles are either herbaceous or scarious. Flowers are regular with an herbaceous or scarious perianth of (one to) mostly five (rarely to eight) tepals, often joined.
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The leaves are alternate, simple, blades 5 to 7 centimeters long, and 2 to 3.5 centimeters in width, shallowly toothed, and finely hairy. The winter buds are brown and hairy, similar to those of other hackberries, but smaller, only 1 to 2 mm. long. Terminal buds absent. Flowers are monecious and unisexual, occurring either solitarily or in small clusters.
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The inflorescences are bracteate racemes or cymes. The flowers are hermaphroditic (bisexual), rarely unisexual (androdioecious), actinomorphic (rarely zygomorphic). The perianth is placed on a hypanthium that may be free or may be partly fused with the ovary (which is then semi-inferior). There are usually five sepals, but there may be three to ten, fused with the hypanthium, occasionally petaloid.
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Ficus carica is a gynodioecious, deciduous tree or large shrub that grows up to tall, with smooth white bark. Its fragrant leaves are long and wide, and are deeply lobed (three or five lobes). The fig fruit develops as a hollow, fleshy structure called the syconium that is lined internally with numerous unisexual flowers. The tiny flowers bloom inside this cup-like structure.
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Embryonic mortality in parthenogenic amphibians is high. Hatching rates for North American salamander species have ranged from 19.5% to 30.5%. It is speculated that intergenomic exchanges, like crossing over during meiosis, may play a role. Intergenomic exchanges are often lethal due to the fact that chromosomes in unisexual species are homeologous (similar, but less so than homologous chromosomes from within a species).
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The Cucurbitales are an order of flowering plants, included in the rosid group of dicotyledons. This order mostly belongs to tropical areas, with limited presence in subtropic and temperate regions. The order includes shrubs and trees, together with many herbs and climbers. One major characteristic of the Cucurbitales is the presence of unisexual flowers, mostly pentacyclic, with thick pointed petals (whenever present).
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The leaves are large, coarse, hairy pinnately-lobed and alternate; they get stiff and rough when old. The plant has branching tendrils. The white to yellow flowers grow singly in the leaf axils and the corolla is white or yellow inside and greenish- yellow on the outside. The flowers are unisexual, with male and female flowers occurring on the same plant (monoecious).
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Stipules are absent. The many small flowers of Spiraea shrubs are clustered together in inflorescences, usually in dense panicles, umbrella-like corymbs, or grape-like clusters. The radial symmetry of each flower is five fold, with the flowers usually bisexual, rarely unisexual. The flowers have five sepals and five white, pink, or reddish petals that are usually longer than the sepals.
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It is generally dioecious, but it may have unisexual and bisexual flowers on one plant, or all female or all bisexual flowers on a single plant. It can reproduce sexually or vegetatively by sprouting new plants from its root crown. The fruit is a hairy nutlet. This plant can be found on Santa Cruz and San Miguel Islands off Southern California coast.
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The flowers are unisexual. Its flowers have 3 sepals, 0.8-1 by 0.5 millimeters. The sepals are smooth on their upper surface, hairy on their lower surface, and have fine hairs on their margins. Its 6 petals are arranged in two rows of 3. The outer elliptical petals are 1.5 by 1-1.5 millimeters with smooth upper surfaces and densely hairy lower surfaces.
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There are glands at the tips of the marginal teeth. The flowers grow in clusters or singly in the axils of the leaves. They are unisexual, with male flowers being on a different tree from female flowers. They are yellowish-green and fragrant, and are followed by globular, fleshy fruit up to in diameter which turn orangish- red as they ripen.
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Tripsacum dactyloides has separate female and male flowers on the same individual making it a monoecious plant. The inflorescence of the terminal axillary bud is long. The type of inflorescence is usually a single raceme or a panicle with a combination of two to three unisexual single racemes. Fruits: The seed-producing season of the grass is from June to September.
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These plants have the ability to easily release their leaves in strong winds, a supposed adaption serving to prevent toppling during hurricanes. Inflorescences occur beneath the crownshaft, emerging from a narrow, horn- shaped bract. The flowers on the branched panicles are usually white, unisexual, and contain both sexes. The fruit is an oblong or globose drupe long and deep purple when ripe.
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The inflorescences may be terminal or axillary, and are in the form of spikes or clusters, with at most very short peduncules (flowering stems). Individual flowers have pedicels (stalks). The flowers may be bisexual or unisexual, with sometimes a mixture of staminate, pistillate and bisexual flowers on the same plant. There are five white to greenish white tepals, joined at the base.
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Schisandaceae are pollinated predominantly by nocturnal gall midges that lay their eggs in the male and female flowers (in Schisandraceae species with unisexual flowers) or the male-stage and female-stage flowers (in species with bisexual flowers). The larvae of these midges develop in the floral tissue once it has dropped to the ground, feeding on floral exudates (not ovules or pollen).
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The inflorescences are usually in the axils of leaves, rarely below the leaves or at the ends of stems. In Uapaca, the flowers are in a pseudanthium, a tight bundle of flowers that resembles a single flower. Except for four species of Aporosa, the flowers are unisexual, the plants being either monoecious or dioecious. The flowers are actinomorphic in form.
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Amaranth has a primary root with deeper spreading secondary fibrous root structures. Inflorescences are in the form a large panicle that varies from terminal to axial, color, and sex. The tassel of fluorescence is either erect or bent and varies in width and length between species. Flowers are radially symmetric and either bisexual or unisexual with very small, bristly perianth and pointy bracts.
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The flowers are unisexual, with male and female flowers growing on separate trees. Pollen is transferred from one flower to another flower by wind and insects. Fruits stay green until near maturity, when they darken to purple or black before falling to the ground. The berries are 6-7 mm long, appearing in mid-summer and ripening from autumn to winter.
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Streblus smithii (also known as Smith's milkwood and the Three Kings milk tree) is a species of plant in the family Moraceae. It is endemic to Three Kings Islands, New Zealand. The bark exudes a thick white (often referred to as a milk-like) sap when cut. The flowers are small and unisexual and the fruit is either achene or drupe.
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The flowers are arranged in panicles, 100–150 mm long. The green or purple flowers are large and unisexual as the tree is dioecious (male and female flowers are found on different trees). The pollens are oval in shape, approximately 40 microns in length. The calyx is dull orange and is divided into five sepals, each one 10-13 mm long.
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Leaf margins are serrate or rarely entire. Most species have yellowish green, small, bisexual or unisexual, rarely polygamous flowers; which are produced singly or in axillary cymes, cymose racemes, or cymose panicles containing a few flowers. Calyx tube campanulate to cup-shaped, with 4 or 5 ovate-triangular sepals, which are adaxially ± distinctly keeled. Petals 4 or 5 but a few species may lack petals.
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The Castilleae are a tribe within the plant family Moraceae. It includes eight to 11 genera and 55–60 species including Castilla, the Panama rubber tree. Members of the tribe are primarily Neotropical with two Afrotropical genera, one genus in New Guinea, and one in New Caledonia. The tribe's distinctive inflorescence is unisexual in monoecious species, with discoid to urceolate receptacles with involucrate bracts.
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Antoine Nicolas Duchesne is important in the development of strawberries in both France, and the rest of the world. He discovered that strawberries can be either bisexual, or unisexual. He also conducted experiments, crossing F. moschata and F. chiloensis. The resulting large fruit put Duchesne in King Louis XV's favor and allowed him to continue to study and create his categorization of the ten "races" of strawberry.
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Pilea pumila is an erect annual, growing 0.7 to 70 cm tall. The foliage is opposite, simple with dentate margins, wrinkly (with depressed veins), ovate, and with long petioles. Both the leaves and stems are translucent and bright green, turning bright yellow in autumn. The flowers are small, borne in axillary cymes, unisexual with both genders occurring on the same plant, greenish yellow, and pollinated by wind.
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Mature Rafflesia arnoldii flower with buds Rafflesia arnoldii is rare and fairly hard to locate. It is especially difficult to locate the flower in forests, as the buds take many months to develop and the flower lasts for just a few days. The flowers are unisexual and thus proximity of male and female flowers is vital for successful pollination. These factors make successful pollination a rare event.
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G. tenuispina Gymnosporia is an Old World genus of plants, that comprise suffrutices, shrubs and trees. It was formerly considered congeneric with Maytenus, but more recent investigations separated it based on the presence of achyblasts (truncated branchlets) and spines, alternate leaves or fascicles of leaves, an inflorescence that forms a dichasium, mostly unisexual flowers, and fruit forming a dehiscent capsule, with an aril on the seed.
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Flower of sweetgum The flowers typically appear in spring and persist into autumn/fall, sometimes persisting into winter. They are typically about in diameter and are covered with rusty hairs. The flowers are unisexual and greenish in color. Staminate flowers in terminal racemes two to three inches long, the pistillate in a solitary head on a slender peduncle borne in the axil of an upper leaf.
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Palms of the genus Wettinia are monoecious, medium-sized to large, and typically solitary-trunked. They have a low, dense cone of brown or black stilt roots, and pinnate leaves. The rope-like inflorescences of the plant emerge from leathery spathes, and grow in a circular pattern around one or more trunk rings beneath the crown shaft. They are unisexual, fleshy, and cream colored or white.
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Hedyscepe canterburyana, the big mountain palm or umbrella palm, is the sole species in the genus Hedyscepe of the family Arecaceae. It is endemic to Lord Howe Island, Australia and is threatened by habitat loss. It is a solitary palm with a distinct crownshaft, and bears unisexual flowers of both sexes. With the Rhopalostylis palms of Norfolk Island and New Zealand it forms the botanic subtribe Rhopalostylidinae.
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The long inflorescences emerge at each leaf node, from top to bottom, producing pendent clusters of white, unisexual flowers. The fruit matures to a round, drupe, red in color with one seed. Like all Caryotas, the fruit contains oxalic acid, a skin and membrane irritant. As these plants are monocarpic, the completion of the flower and fruiting process results in the death of the tree.
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In the tribe Ochneae, all of the species have actinomorphic flowers. In the subtribe Ochninae, and in the genus Froesia, the components of the ovary (carpels) are very shortly united at the base. Otherwise, the ovary in Ochnaceae is syncarpous, consisting of carpels that are completely fuzed. In Medusagyne and Quiinoideae, many of the flowers are unisexual, except in Froesia, where they are strictly hermaphrodite.
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The inflorescences consist of axillary or terminal spikes or spicate panicles, or axillary clusters of glomeruled flowers. The flowers are unisexual, some species are monoecious, others dioecious. Male flowers consist of 3-5 perianth lobes and 3-5 stamens. Female flowers are usually lacking a perianth, but are enclosed by 2 foliaceous bracteoles, and contain an ovary with a short style and 2 stigmas.
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Unisexual (all-female) populations of ambystomatid salamanders are widely distributed across the Great Lakes region and northeastern North America. The females require sperm from a co-occurring, related species to fertilize their eggs and initiate development. Usually the eggs then discard the sperm genome and develop asexually (i.e., gynogenesis, with premeiotic doubling); however, they may incorporate the genome from the sperm into the resulting offspring.
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Pimelea pauciflora is a small shrub high with smooth, long, reddish stems. The leaves are arranged opposite along the branches, glossy green, smooth, narrow- linear or linear lance shaped, long, wide on a short stem. The inflorescence consists of 3-9 yellowish-green flowers mostly at the end of branches in small clusters. The flowers are unisexual, smooth, male flowers long, female about long.
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In the axil of each bract, there are one to five (rarely to twelve) flowers, free or sometimes fused to each other, to the bract, and to the inflorescence axis. The flowers are usually bisexual (the lateral flowers may be unisexual). The 2-5-lobed perianth consists of two to five connate tepals. There are one or two stamens and an ovary with mostly two stigmas.
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The species is dioecious (unisexual) with male and female flowers on different individual trees. The inflorescences are terminal, branched, panicles about 12–20 cm long, on stout peduncles, holding rusty tomentose buds and yellow or yellowish-white flowers. The male flowers are 7 mm across, with 4 tepals (2 mm) and ovate containing many stamens (filaments to 3 mm). Female flowers are 5 mm across and with 4 tepals (2 mm).
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The gametophyte is unisexual and will produce either sperm or egg and not both at the same time. Sperm is transported, often by water, to an archegonium located on the top of a female gametophyte shoot. Once an egg has been fertilized, it develops a diploid sporophyte structure which is composed of a foot, seta, sporangium, and operculum. The foot supplies the developing sporangium with nutrients from the gametophyte.
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The inflorescence of C. dipsaceus is monoecious and unisexual with each plant having separate male and female flowers. The male flowers range from 1-1.2 x 2-2.5cm, are “corolla yellow,” and have three stamens with 2mm long anthers. Female flowers range from 2-2.3 x 2-2.2cm, are also “corolla yellow”, and have three-lobed stigmas. Both the male and female flower sexes do not have bracts.
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Gynogenetic species, "gynogens" for short, are unisexual, meaning they must mate with males from a closely related bisexual species that normally reproduces sexually. It’s a disadvantageous mating system for males, as they are unable to pass on their DNA. The question as to why this reproductive mode exists, given that it appears to combine the disadvantages of both asexual and sexual reproduction, remains unsolved in the field of evolutionary biology.
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Acrocomia is a genus of spiny, pinnate-leaved palms which range from large trees to small palms with short, subterranean stems. The species bears branched inflorescences which are located among the leaves. The unisexual flowers; female flowers are born near the base of the inflorescence, while male flowers are borne towards the tips. Fruit are large, single-seeded, and vary in colour from yellow, to orange, to brown.
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Both hermaphrodite and monoecious species have the potential for self- pollination leading to self-fertilization unless there is a mechanism to avoid it. Eighty percent of all flowering plants are hermaphroditic, meaning they contain both sexes in the same flower, while 5 percent of plant species are monoecious. The remaining 15% would therefore be dioecious (each plant unisexual). Plants that self-pollinate include several types of orchids, and sunflowers.
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Flowers are bisexual (rarely unisexual), with up to five tepals connate only basally or fused to form sac, one to five stamens, and a superior ovary with one to three filiform stigmata. Fruits and seeds of Dysphania botrys The fruit is often enclosed in perianth. The membranous pericarp is adherent or nonadherent to the horizontal or vertical, subglobose, or lenticular seed. The seed coat is smooth or rugose.
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Flora of Pakistan University of Karachi, KarachiFlora of China Vol. 11 Page 258 黄蓉花属 huang rong hua shu Dalechampia Linnaeus, Sp. Pl. 2: 1054. 1753. Dalechampia has unisexual flowers that are secondarily united into bisexual blossoms (pseudanthia), which act as the pollination units. The pollination and floral evolution of this genus have been studied more intensively than perhaps any other member of the euphorbia family.
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Their blades are cup- or collar-like or deltoid to semi-circular scales. In the axil of each bract, there are three to five (rarely one or seven) flowers, free or sometimes fused to each other, to the bract, and to the inflorescence axis. The flowers are hermaphrodite, rarely unisexual. They consist of a 2-3-lobed perianth of connate tepals, one stamen, and an ovary with two stigmas.
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Sphagnum, like all other land plants, has an alternation of generations; like other bryophytes, the haploid gametophyte generation is dominant and persistent. Unlike other mosses, the long-lived gametophytes do not rely upon rhizoids to assist in water uptake. Sphagnum species can be unisexual (male or female, dioecious) or bisexual (male and female gametes produced from the same plant; monoecious); In North America, 80% of Sphagnum species are unisexual.Andrus, Richard. Sphagnum.
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Plant diagram Trichosanthes cucumerina is a monoecious annual vine climbing by means of tendrils. Leaves are palmately lobed, up to 25 cm long. Flowers are unisexual, white, opening at night, with long branching hairs on the margins of the petals. These hairs are curled up in the daytime when the flower is closed, but unfurl at night to form a delicate lacy display (see photos in gallery below).
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Biota of North America Program 2014 county distribution mapCalflora taxon report, University of California @ Berkeley Vitis girdiana is a woody vine with a coating of woolly hairs, especially on new growth. The woolly leaves are heart-shaped to kidney-shaped with toothed edges and sometimes shallow lobes. The inflorescence is a panicle of unisexual flowers. The fruit is a spherical black grape usually not more than 8 millimeters wide.
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It forms white solitary flowers that are axillary and can be bisexual or unisexual. Capsules form later that are obconical to obovoid in shape and slightly asymmetric. They are usually in length with a diameter. The plant flowers during the summer months between November and March producing a carpet of white-blue five-petalled star-shaped flowers that are ideal as groundcovers in garden beds, rockeries or between paving stones.
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This genus of dioecious evergreen trees and shrubs has 140 species, in tropical and subtropical regions of Asia, with 17 Chinese species, 13 of which are endemic. The trees are 3 to 25 m tall, with leaves usually clustered or nearly verticillate, rarely alternate or opposite, unlobed, pinninerved, and rarely triplinerved. The flowers are star-shaped, small, and greenish. The flowers are clustered or whorled and are unisexual.
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Most fig-marigolds are herbaceous, rarely somewhat woody, with sympodial growth and stems either erect or prostrate. Leaves are simple, opposite or alternate, and more or less succulent with entire (or rarely toothed) margins. Flowers are perfect in most species (but unisexual in some), actinomorphic, and appear singularly or in few-flowered cymes developing from the leaf axils. Sepals are typically five (3-8) and more or less connate (fused) below.
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The flowers are commonly borne in definite or indefinite axillary inflorescences, which are often reduced to a single flower, but may also be cauliflorous, oppositifolious, or terminal. They often bear supernumerary bracts in the structure of a bicolor unit. They can be unisexual or bisexual, and are generally actinomorphic, often associated with conspicuous bracts, forming an epicalyx. They generally have five valvate sepals, most frequently basally connate, with five imbricate petals.
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Detail of a male flowering catkin on a willow (Salix sp.) A catkin or ament is a slim, cylindrical flower cluster (a spike), with inconspicuous or no petals, usually wind-pollinated (anemophilous) but sometimes insect-pollinated (as in Salix). They contain many, usually unisexual flowers, arranged closely along a central stem that is often drooping. They are found in many plant families, including Betulaceae, Fagaceae, Moraceae, and Salicaceae.
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In all other cases of unisexual reptilian species that have been examined, multiple separate asexual lineages are present. As true parthenotes, Lacerta do not require stimulation from sperm to reproduce. The best-known and perhaps most evolutionarily derived example of parthenogenesis in reptiles occurs within the Teiid genus of whiptail lizards known as Cnemidophorus. This genus contains at least 13 truly parthenogenetic species, which originate from hybridization events between sexual Cnemidophorus species.
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This particular parthenogentic mechanism has been observed in unisexual Ambystoma species as well as Glandirana rugosa. The second potential mechanism is apomixis, which produces a complete set of chromosomes through mitotic replication. This method has not been observed in any amphibious species. Courtship behavior between females of the same species has been observed in Ambystoma platineum, and has been posited to induce either oviposition of ovulation, though the precise utility of the behavior is unknown.
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The flowers are unisexual. Male flowers: perianth segments 6 in 2 whorls, outer ones broader, inner ones slightly narrow and pubescent outside; fertile stamens 12; filaments pubescent, of 3rd whorls each with 2 large glands at base, of 4th whorls with smaller glands; rudimentary pistil pubescent or glabrous. Female flowers: ovary pubescent or glabrous. Fruit ellipsoid, 10–12 × 7–9 mm, seated on discoid perianth tube; fruiting pedicel of 5 mm, stout.
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Flowers are small, white, and unisexual. Female flowers have an inferior ovary, the fruit is a fleshy capsule 4–13 mm long and 2–5 mm in diameter, and seeds are 1 mm long, ellipsoid, and hairy. Limnobium laevigatum, or Smooth Frogbit can be distinguished from Limnobium spongia, American frogbit, by flower and leaf characteristics as well as range; American frogbit is not known to occur in western states unlike smooth frogbit.
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These are evergreen perennial herbs with stems growing erect or decumbent and creeping. Stems that grow along the ground may root at the nodes. There is generally a crown of wide leaf blades which in wild species are often variegated with silver and green coloration. The inflorescence bears unisexual flowers in a spadix, with a short zone of female flowers near the base and a wider zone of male flowers nearer the tip.
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A gametophyte can be monoicous (bisexual), producing both eggs and sperm or dioicous (unisexual), either female (producing eggs) or male (producing sperm). In the bryophytes (liverworts, mosses and hornworts), the sexual gametophyte is the dominant generation. In ferns and seed plants (including cycads, conifers, flowering plants, etc.) the sporophyte is the dominant generation. The obvious visible plant, whether a small herb or a large tree, is the sporophyte, and the gametophyte is very small.
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Members of the birch family (Betulaceae) are examples of monoecious plants with unisexual flowers. A mature alder tree (Alnus species) produces long catkins containing only male flowers, each with four stamens and a minute perianth, and separate stalked groups of female flowers, each without a perianth. (See the illustration of Alnus serrulata.) Most hollies (members of the genus Ilex) are dioecious. Each plant produces either functionally male flowers or functionally female flowers.
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Members of Poikilospermum are shrubs or tall woody climbers (also known as lianas). The petiolate leaves are alternate; their stipules are often caducous, intrapetiolar, connate, and leathery; their veins are often prominently pinnate; cystoliths occur adaxially in circular groups, abaxially along veins, either punctiform or linear. The inflorescences are solitary and axillary dichotomously branched cymes, they are unisexual (the plants are dioecious). The glomerules are capitate and either on swollen peduncular receptacles (in P. subgen.
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The main point of contention in research of Ascarina lies in the primitive nature of the flower. Ascarina flowers are naked and unisexual with one carpel in females, and between one and five in males. The male flowers have a morphology that suggests that they have been reduced from a more evolved form, rather than simply retaining more primitive features. There are several pieces of evidence that indicate the reduction of the Ascarina genera.
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Quercus humboldtii is an evergreen tree which grows to a height of 25 meters and a diameter of 1 meter, with buttresses of up to 1 meter. Its bark is reddish grey or grey and fissured, breaking into squares and flaking. The leaves simple, alternate and lanceolate, up to 10–20 cm long, and clustered at the ends of the branches. The flowers are small, yellow, and unisexual, with a racemic inflorescence.
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The tiny white or pink flowers are attached to the stems. They are bisexual or unisexual, produced in clusters of three to many together in the leaf axils. The nickname sticky-weed is due to the adherent quality of the flowers and of the hairy stems; unlike some related species of the family Urticaceae, the hairs do not sting. The flowering period extends from spring through autumn, when it produces large amounts of pollen.
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Bosea cypria is a species of flowering plant in the Amaranthaceae family. It is a highly branched, evergreen shrub, 1–2 m high, erect, suberect, or hanging on walls, cliffs or trees, with hairless angular shoots. Leaves, opposite, simple, entire-+ elliptical, 2-6 x (1-2-3) cm, hairless, petiolate, dark green, occasionally red green. Flowers in branched spikes, hermaphrodite or unisexual 5-merous, very small, green brown, the floral symmetry is actionomorphic.
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The tribes containing the largest number of heterostylous species are Spermacoceae and Psychotrieae. Heterostyly is absent in groups that have secondary pollen presentation (e.g. Vanguerieae). Unisexual flowers also occur in Rubiaceae and most taxa that have this characteristic are dioecious. The two flower morphs are however difficult to observe as they are rather morphologically similar; male flowers have a pistillode with the ovaries empty and female flowers have empty, smaller anthers (staminodes).
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Andricus opertus, the fimbriate gall wasp, is a species of wasp in the family Cynipidae whose bisexual generation induces elongate, spiky galls on the leaves of various species of oaks in California, including valley oak and scrub oak. The galls of the bisexual generation form in spring, adults emerge in late spring, and galls persist on trees until the fall. The unisexual generation of this species forms aborted bud galls in the summer and fall.
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The species is monoecious, with the flowers borne in separate unisexual heads: staminate (male) heads situated above the pistillate (female) heads in the inflorescence. The pistillate heads consist of two pistillate flowers surrounded by a spiny involucre. Upon fruiting, these two flowers ripen into two brown to black achenes and they are completely enveloped by the involucre, which becomes a bur. The bur, being buoyant, easily disperses in the water for plants growing along waterways.
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Most anthozoans are unisexual but some stony corals are hermaphrodite. The germ cells originate in the endoderm and move to the gastrodermis where they differentiate. When mature, they are liberated into the coelenteron and thence to the open sea, with fertilisation being external. To make fertilisation more likely, corals emit vast numbers of gametes, and many species synchronise their release in relation to the time of day and the phase of the moon.
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All Artocarpus species are laticiferous trees or shrubs that are composed of leaves, twigs and stems capable of producing a milky sap. The fauna type is monoecious and produces unisexual flowers; furthermore, both sexes are present within the same plant. The plants produce small, greenish, female flowers that grow on short, fleshy spikes. Following pollination, the flowers grow into a syncarpous fruit, and these are capable of growing into very large sizes.
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The hermaphrodite or unisexual flowers are more or less radially symmetric, with a perianth of three or four fleshy tepals connate nearly to the apex, one or two stamens, and an ovary with two or three stigmas. The perianth is persistent in fruit. The fruit wall (pericarp) is membranous. The vertical seed is ellipsoid, with light brown, membranous, hairy seed coat, the hairs can be strongly curved, hooked, or conic, straight or slightly curved.
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Within the carpel the megasporangium form the ovules, with its protective layers (integument) in the megaspore, and the female gametophyte. Unlike the male gametophyte, which is transported in the pollen, the female gametophyte remains within the ovule. Most flowers have both male and female organs, and hence are considered bisexual (perfect), which is thought to be the ancestral state. However, others have either one or the other and are therefore unisexual, or imperfect.
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In which case they may be either male (staminate) or female (pistillate). Plants may bear either all bisexual flowers (hermaphroditic), both male and female flowers (monoecious), or only one sex (dioecious), in which case separate plants are either male or female flower-bearing. Where both bisexual and unisexual flowers exist on the same plant, it is called polygamous. Polygamous plants may have bisexual and staminate flowers (andromonoecious), bisexual and pistillate flowers (gynomonoecious), or both (trimonoecious).
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They are greenish-yellow or sometimes fully green with purple or brownish stripes. The spathe, known in this plant as "the pulpit" wraps around and covers over and contain a spadix ("Jack"), covered with tiny flowers of both sexes. The flowers are unisexual and sequential hermaphrodites, in small plants most if not all the flowers are male, as plants age and grow larger the spadix produces more female flowers. This species flowers from April to June.
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Sycamore trees produce their flowers in hanging branched clusters known as panicles that contain a variety of different flower types. Most are morphologically bisexual, with both male and female organs, but function as if they were unisexual. Some are both morphologically and functionally male, others morphologically bisexual but function as males, and still others are morphologically bisexual but function as females. All of the flower types can produce pollen, but the pollen from functionally female flowers does not germinate.
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It is the latter's Kingdom Come that the Third Testament was supposed to lead to. Seeing both God and man as intrinsically unisexual, Merezhkovsky regarded a male/female schism to be a symptom of imperfection, the cause for primal human being's fatal disintegration. In the modern times, according to Merezhkovsky, both monastic and ascetic Christianity will cease to exist. Art would not just adopt religious forms, but become an integral part of religion, the latter taken in broader concept.
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Kleptogenic reproduction results in three potential outcomes. A unisexual female may simply activate cell division in the egg through the presence of a male's sperm without incorporating any of his genetic material—this results in the production of clonal offspring. The female may also incorporate the male's sperm into her egg, but can do so without excising any of her genetic material. This results in increased ploidy levels that range from triploid to pentaploid in wild individuals.
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This facet of kleptogenesis was recently ascertained from genetic research that indicates there is no ancestral A. laterale genome that is maintained from one unisexual to the next, and that there is not a specific "L" genome that is found more often than others. "L" genetic material found in these salamanders has also not evolved to be substantially unique from sexual genomes. Examples species exhibiting the property include the water frogs in Europe in the genus Pelophylax.
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Anthers are basifixed and open lengthwise. The flowers are bisexual, less commonly unisexual (more or less dioecious). Ovaries superior to partially inferior, with carpels equal to the number of petals, each forming a single locule, superior, free or almost so, basally with a small to conspicuous basal nectary scale, gradually tapering to a short to long style with few to many ovules. The fruit is usually capsular with dehiscent follicles, opening along the carpal suture and many seeded.
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Each flower is on a densely hairy pedicel 2-4 millimeters in length. The flowers are unisexual. Its flowers have 3 oval-shaped sepals, 0.8 by 1 millimeters, that have blunt tips. The outer surface of the sepals is densely hairy while the inside is smooth, and their margins have very fine hairs. Its 6 petals are arranged in two rows of 3. The outer petals are white or yellow-green and 2 by 2 millimeters.
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From small to moderate to the tallest in the family, the trunks may be solitary or clustering and lack armament. The reduplicate leaf is regularly or irregularly pinnate, bifid, or entire with pinnate ribs; crownshafts are present in some members and absent in others. Monoecious, dioecious, and hermaphroditic palms occur in the group; a protective prophyll accompanies the inflorescence, and all feature peduncular bracts. Any unisexual flowers are slightly dimorphic, solitary, or in rows; all have syncarpous, triovulate gynoecium.
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When A. chilensis flowers at the end of spring, the white flowers are unisexual and small, but they eventually yield a small edible fruit. The small purple-black berries that form are approximately in diameter and contain 4 to 8 angled seeds. A seven-year-old tree can produce up to of berries per year. With fruit that tastes similar to blackberries, the species is known as the Chilean wineberry, and locally in Spanish as maqui or maque.
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Some flowers are self-pollinated and use flowers that never open or are self-pollinated before the flowers open, these flowers are called cleistogamous. Many Viola species and some Salvia have these types of flowers. Conversely, many species of plants have ways of preventing self-fertilization. Unisexual male and female flowers on the same plant may not appear or mature at the same time, or pollen from the same plant may be incapable of fertilizing its ovules.
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65(12) 40-41. The flowers are inconspicuous and incomplete, no petals and 3-4 greenish-yellow sepals, diameter. The fruit is a berry, white, yellow, orange, or red when mature, containing one to several seeds embedded in very sticky juice, called viscin. The flowers are unisexual, and depending on the species, the plant will be monoecious or dioecious (both male and female flowers on a single plant or male and female plants with only one sex of flowers).
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Leaf of Fagus sylvatica Beechnuts in autumn The European beech (Fagus sylvatica) is the most commonly cultivated, although few important differences are seen between species aside from detail elements such as leaf shape. The leaves of beech trees are entire or sparsely toothed, from long and broad. Beeches are monoecious, bearing both male and female flowers on the same plant. The small flowers are unisexual, the female flowers borne in pairs, the male flowers wind-pollinating catkins.
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Most Rubiaceae are zoophilous. Entomophilous species produce nectar from an epigynous disk at the base of the corolla tube to attract insects. Ornithophily is rare and is found in red-flowered species of Alberta, Bouvardia, and Burchellia. Anemophilous species are found in the tribes Anthospermeae and Theligoneae and are characterized by hermaphroditic or unisexual flowers that exhibit a set of specialized features, such as striking sexual dimorphism, increased receptive surface of the stigmas and pendulous anthers.
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It is an evergreen small tree or shrub that measures up to 5 m (16 ft) tall, the bark is greyish-brown and sheds in longitudinal strips. Leaves are alternate, very leathery, with toothed edge and linear shape, the leaves are petiolate, glossy light-green about 9 cm long. The flowers are unisexual star-shaped and white, solitary or clustered in axillary inflorescences. The calyx is formed by 5 sepals, the corolla is made up by 5 petals.
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Rhodostemonodaphne is a genus of flowering plants in the family Lauraceae. It is a neotropical genus consisting of approximately 41 species occurring in Central America and northern South America. This genus has many species that are valued for timber. The classification of the genus is unclear since the species in the genus fall into a well-supported but unresolved clade that also includes species with unisexual flowers currently placed in the genera Endlicheria and part of Ocotea.
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It is an evergreen small tree or shrub that measures up to 5 m (16 ft) tall, the leaves are alternate, very leathery, with toothed edge and oblong shaped, the leaves are petiolate, yellowish-green, about 3–6 cm long. The flowers are unisexual star-shaped and white, solitary or clustered in axillary inflorescences. The calyx is formed by 5 sepals, the corolla is made up by 5 petals. The male ones have 15-20 stamens.
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The family Araliaceae, to which the genus Polyscias including Ming aralia belongs, gives rise to a multitude of trees or shrubs that contain gum and resin ducts. As a whole, the family contains plants that have leaves of alternate, palmately or pinnately compound or simple, with stipules. The inflorescences are generally umbellate, and often arranges in compound umbels, caouttules, panicles or races. They possess flowers of smaller size than the dioecious which are bisexual or unisexual.
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Phoenix sylvestris ranges from 4 to 15 m in height and 40 cm in diameter; not as large as the Canary Island Date Palm, but nearly so, and resembling it. The leaves are 3 m long, gently recurved, on 1 m petioles with acanthophylls near the base. The leaf crown grows to 10 m wide and 7.5 to 10 m tall containing up to 100 leaves. The inflorescence grows to 1 metre with white, unisexual flowers forming to a large, pendent infructescence.
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They are usually irregular, though in some case they may be slightly irregular, and either bisexual or unisexual. The perianth segments are in 1 or 2 series of (2–)3 free segments; the inner series when present are usually showy and petal-like. Stamens 1–numerous, in 1 or more series; the inner ones sometimes sterile. Pollen is globular and free but in the marine genera (Thalassia and Halophila) – the pollen grains are carried in chains, like strings of beads.
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The leaves of all four of these species may or may not have white spots. There are male (staminate) and female (pistillate) flowers (unisexual flowers) on a single plant (monoecious), and these grow singly, appearing from the leaf axils. Flowers have five fused yellow to orange petals (the corolla) and a green bell-shaped calyx. Male flowers in Cucurbitaceae generally have five stamens, but in Cucurbita there are only three, and their anthers are joined together so that there appears to be one.
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In hybridogenesis, females of a unisexual species mate with a male of a related species and utilize their genetic material in order to produce offspring. However, in spite of this requirement, the genetic material of the male is not passed on to the next generation. Just prior to meiosis, during mitotic division, spindle fibers attach to the maternal chromosomes, leaving the paternal chromosomes in the cytoplasm. The paternal chromosomes are therefore excluded from nascent eggs, without recombination having typically occurred.
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In homothallic sexual reproduction, two haploid nuclei derived from the same individual fuse to form a zygote that can then undergo meiosis. Homothallic fungi include species with an aspergillus-like asexual stage (anamorphs) occurring in numerous different genera, several species of the ascomycete genus Cochliobolus, and the ascomycete Pneumocystis jiroveccii. Heitman reviewed evidence bearing on the evolution of sexual reproduction in the fungi and concluded that the earliest mode of sexual reproduction among eukaryotes was likely homothallism, that is, self-fertile unisexual reproduction.
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The unisexual (all female) hybridogenetic fish Poeciliopsis monacha—occidentalis is an ancient clonal lineage that appears to be more than 100,000 generations old. P. monacha was the maternal ancestor of this lineage and P. occidentalis was the paternal ancestor. In these hybridogenetic fish only the haploid maternal P. monacha genome (M), but not the paternal genome, is transmitted to ova (hemiclonal reproduction). The paternal P. occidentalis genome (O) is excluded during a pre-meiotic cell division, thus avoiding synapsis and crossing-over.
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The sex chromosomes in bryophetes affect what type of gamete is produced by the gametophyte, and there is wide diversity in gametophyte type. Unlike seed plants, where gametophytes are always unisexual, in bryophytes they may produce male, female, or both types of gamete. Bryophytes most commonly employ a UV sex- determination system, where U produces female gametophytes and V produces male gametophytes. The U and V chromosomes are heteromorphic with U larger than V, and are frequently both larger than the autosomes.
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Although most Rubiaceae species are hermaphroditic, outbreeding is promoted through proterandry and spatial isolation of the reproductive organs. More complex reproductive strategies include secondary pollen presentation, heterodistyly, and unisexual flowers. Secondary pollen presentation (also known as stylar pollen presentation or ixoroid pollen mechanism) is especially known from the Gardenieae and related tribes. The flowers are proterandrous and the pollen is shed early onto the outside of the stigmas or the upper part of the style, which serve as a 'receptaculum pollinis'.
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Sandpaper tree is a small to medium-sized tree in the banyan group of figs, growing to . The trunk develops aerial and buttressing roots to anchor it in the soil and help support heavy branches. It has almost distichous and alternate which are almost opposite, simple; blade ovate to elliptical or obovate; base acute to obtuse; apex shortly acuminate, acute or obtuse; and margin toothed to entire. Flowers are unisexual and are pink, purplish, or yellow, becomes orange or red at maturity.
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Leaflets obovate-oblong to oblong-cuneate, thinly coriaceous, coarsely serrate-dentate. Flowers usually unisexual; inflorescences are compound umbels with 8-20 primary branchlets up to 10 cm long, 15-20 secondary rays, umbellules with 10-15 flowers in each. Calyx truncate or obscurely 5-toothed; flowers 5mm in diameter, sweet-scented; petals 5, white to pink flushed, ovate to triangular, acute; stamens 5; ovary 2-loculed, each containing 1(-2) ovules; style branches 2, spreading. Fruit fleshy, very dark purple, laterally compressed, 5–8 mm diam.
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A laurel shrub Laurus nobilis in pot Laurus nobilis bloomed The laurel is an evergreen shrub or small tree, variable in size and sometimes reaching tall. The genus Laurus includes four accepted species, whose diagnostic key characters often overlap.Mabberley, The Plant-Book: A Portable Dictionary of the Vascular Plants, Cambridge University Press, 19 Jun 1997 The bay laurel is dioecious (unisexual), with male and female flowers on separate plants. Each flower is pale yellow-green, about diameter, and they are borne in pairs beside a leaf.
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Lianas or reclining shrubs with oblong-lanceolate to ovate leaves. The flowers, which may be unisexual or bisexual, are in axillary racemoids or fascicles, with a white to orange corollas that are strongly zygomorphic (bilaterally symmetrical) with the long bottom petal weakly differentiated with a well exserted (projecting) spur. On the five stamens, the filaments are strongly connate (fused) with the two lowest anthers calcarate (spurred) and possessing a small dorsal connective appendage that is entire and ovate. In the gynoecium, the style is rostellate (beaked).
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The Big Finish series has restarted Benny's relationship with Jason, but it is strongly implied in The End of the World that he has been killed. The Virgin Missing Adventures novel Burning Heart (also by Stone) hints that Jason and Benny may at one point have children. In the novel, the Sixth Doctor and Peri journey to the 32nd century and meet a man named Kane, who expected the Doctor to recognise him. Kane's first name (never revealed) is "one of those...that were unisexual".
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Fagaceae is a family of flowering plants that includes beeches and oaks, and comprises eight genera with about 927 species. The Fagaceae are deciduous or evergreen trees and shrubs, characterized by alternate simple leaves with pinnate venation, unisexual flowers in the form of catkins, and fruit in the form of cup-like (cupule) nuts. Their leaves are often lobed and both petioles and stipules are generally present. Leaf characteristics of Fagaceae can be very similar to those of Rosaceae and other rose motif families.
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It is threatened by habitat loss. Leaves alternate, petioles 2–7 mm long, aovate, base subcordate, both faces with glands giving to them harsh texture, glaucous above, undulate margins, irregularly serrate; lamina twisted 5–9 cm, notorious pinate venation. Flowers unisexual, small; male solitary, pedicels up to 1 cm, 50 stamens; female flowers in 3 in inflorescences. Fruit cupule with 4 narrow valves, with three yellowish nuts 12–20 mm long, pilose, the two lower triangular, tri-winged, and the internal flat and bi-winged.
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The extreme ends of the spectrum are the predominately solitary bushbuck and at the other end the highly social giant eland. In general the herd size of spiral-horned antelopes are not large as they rarely exceed more than a few dozen individuals, and are mostly sedentary in nature. The herd composition is unisexual which is mostly females and their young. It is currently believed to be the reason why some spiral-horned antelopes practicing herd as a defense mechanism to protect the young predators.
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It is widespread in semi-arid areas in Australia and predominant within New South Wales and Queensland. The plant is a shrub 3-5m high with leafless, sometimes drooping in older branches. This speciesleaves are linear to lanceolate 5-15mm long and its flowers are unisexual, blooming either in clusters or single, with 3-4 hairy sepals 2-3mm long and 2-5 petals 2-5mm long and are greenish white to yellow in colour. Male flowers with 8-6 stamens, as long as the petals.
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Self-impregnated snake in Missouri has another 'virgin birth', UPI, 21 September 2015. Retrieved 3 October 2015. Some of these like the mourning gecko Lepidodactylus lugubris, Indo-Pacific house gecko Hemidactylus garnotii, the hybrid whiptails Cnemidophorus, Caucasian rock lizards Darevskia, and the brahminy blindsnake, Indotyphlops braminus are unisexual and obligately parthenogenetic. Other reptiles, such as the Komodo dragon, other monitor lizards, and some species of boas, pythons, filesnakes, gartersnakes and rattlesnakes were previously considered as cases of facultative parthenogenesis, but are in fact cases of accidental parthenogenesis.
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The most striking characteristic of Dorstenia is their reproductive structure, called pseudanthium (Greek for "false flower") or in Moraceae hypanthium, which is composed of clusters of tiny unisexual flowers on a disc- or cup-shaped receptacle that are often adorned with bracts of various sizes and shapes. The pseudanthiums can be planar, convex, concave, round, oval, square, lobed, twig, star, boot, or tongue-shaped. Their color varies from green to yellowish and reddish to violet and brown. Beneath the pseudanthium, there are usually bracts, scattered or in rows, sometimes carrying appendages.
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The film begins in the city of London, where a 30-year-old man sits in front of a university board of 3 women. Apparently, the subject the man is being assessed in is Psychology of women, so hence the unisexual university board. The man is yet again told he has failed completely in the subject, and as he exits the university he is identified as Cheng (Ekin Cheng) by his colleagues. Not giving up, Cheng decides to continue with the subject, but at this time, his girlfriend decides to end their relationship.
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It includes only a few species of small evergreen trees and shrubs species native to tropical South America.Kew World Checklist of Selected Plant FamiliesLissocarpa in IPNI, The International Plant Names Index Lissocarpa species share various characters with other members of Ebenaceae, e.g., the black color of roots and bark, extrafloral nectaries on abaxial leaf surfaces, a persistent calyx, unisexual flowers, biovulate carpels with pendulous ovules, and a similar wood anatomy producing a hard, dark heartwood timber similar to ebony. They are slow-growing trees found on a wide variety of soils and sites.
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Each individual flowerhead is surrounded by an involucre, consisting of one or two rows of bracts that are often leaf-like and usually not merged. The base of the flowerhead may be conical, convex or sometimes almost spheroidal. On the base of the flowerhead, at the base of each individual flower, are linear to narrowly lanceolate, green, chaffy scales (or paleae) that become woody when seeds are ripening. Each flowerhead may contain a few or up to over one hundred hermaphrodite or unisexual, star-symmetric or mirror-symmetric flowers.
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The blades entire or more frequently dentate or crenate, pinnately or palmately veined. There are several types of inflorescence, terminal or axillary, frequently both, unisexual or androgynous. Male inflorescences spicate, densely flowered, with several flowers at each node subtended by a minute bract. Female inflorescences generally spicate, sometimes racemose or panicle-shaped, with 1–3(–5) flowers at each node, usually subtended by a large bract, increasing and foliaceous in the fruit, generally dentate or lobed; sometimes subtended by a small bract, entire or lobed, non accrescent in the fruit.
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This species is very similar to Laurus novocanariensis. As the result of a recent taxonomic change, Laurus azorica is now restricted to the archipelago of the Azores, whereas former populations of this species from the western Canary islands including Gran Canaria and from the Madeira archipelago have been described as a new species, namely Laurus novocanariensis. The Azores laurel is dioecious (unisexual), with male and female flowers on separate plants. Each flower is fragrant, creamy white, about 1 cm diameter, and they are borne in pairs beside a leaf.
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Slightly toothed edges and the midrib distinct underneath. The leaves are 6.5–13 cm wide and 2.5-4 cm long. The flowers are hermaphrodite or unisexual about 1 cm 1 diameter, tetramerous, clustered in three-flowered axillary racemes, pedicels about 3–5.9 mm. Calyx is made up by four opposite sepals. Androecium made up by 8 stamens arranged in two whorls, those externals are longer and (4–5.44 mm) and opposite to the sepals while the internal's whorls are shorter (3-3.5 mm) and opposite to the petals.
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Blooming from May to June, the flowers are unisexual and are both small, hairy, growing on the same individual tree. Both are arranged on a stem, only staminate flowers' are a lot longer. Also, staminate flowers are arranged spirally on a slim drooping stem — this is called catkins. Staminate catkins are about 5 cm(2 in) long; Staminate flowers are about 3.5 mm(0.14 in) long; 4 - 6 perianths, lobed, hairy outside, glabrous inside; 4 - 9 stamens, filaments 2.5 mm(0.1 in) long, anthers 1 mm(0.04 in) long.
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Ascarina plants are divided into three major species groups, based on the number of stamens per male flower, number of supporting flower bracts and geographic location. The flowers of the Ascarina species are unisexual, containing one to five stamens in male flowers, and a single carpel in females. The exception to this is A. lucida, which can have monoecious flowers. Ascarina plants differ from the other members of the Chloranthaceae family in that male flowers can have more than one stamen, indicative of a reduction from a more advanced form.
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The African and Madagascan species all have bisexual flowers (possessing both male and female parts), whereas many of the American species have flowers that are unisexual (either male or female). The apetalous flowers are in small panicles. The fruits are globose or oblong berries, 3–5 cm in length, hard and fleshy and at the junction of the peduncle part with the fruit covered by a cup-shaped, occasionally flat, cupule, giving them an appearance similar to an acorn. The fruit is dark green, gradually darkening with maturity.
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Coffee tree leaves rolled up by Hoplandrothrips (Phlaeothripidae) damage Some flower-feeding thrips pollinate the flowers they are feeding on, and some authors suspect that they may have been among the first insects to evolve a pollinating relationship with their host plants. Scirtothrips dorsalis carries pollen of commercially important chili peppers. Darwin found that thrips could not be kept out by any netting when he conducted experiments by keeping away larger pollinators. Thrips setipennis is the sole pollinator of Wilkiea huegeliana, a small, unisexual annually flowering tree or shrub in the rainforests of eastern Australia.
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As in other wild cattle ungulates that form unisexual herds, considerable sexual dimorphism was expressed. Ungulates that form herds containing animals of both sexes, such as horses, have more weakly developed sexual dimorphism. During the mating season, which probably took place during the late summer or early autumn, the bulls had severe fights, and evidence from the forest of Jaktorów shows these could lead to death. In autumn, aurochs fed up for the winter and got fatter and shinier than during the rest of the year, according to Schneeberger.
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Each leaf, recurving at its end, is 1.5 m long on 30 cm petioles being light to bright green in color. The stiff pinnae are once-folded with a prominent midrib, 90 cm long, and regularly arranged along the rachis. The infrafoliar inflorescence produces small, white to yellow, unisexual flowers on bright red branches, basally divided to three orders and distally to one. The female flowers are nearly twice as long as the male's, both contain three distinct sepals and petals, the former with 3 staminodes, the latter with 6 stamens.
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The pendant inflorescences are massive and some 3 m in length, bearing unisexual flowers – male flowers at the distal end, female flowers at proximal – with first order branches of 13–32 rachillae very close-packed in almost one plane (see illustration). Raphia spp are monocarpic or hapaxanthic, flowering and fruiting only once, followed by death. Raphia farinifera flowers when the tree is some 20–25 years old, and it takes a further 5–6 years from flowering to ripe fruit, all fruits ripening together. Fruit is oblong to ovoid, 5–10 cm in length, with imbricate, glossy, golden- brown scales.
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Flower The flowers are fragrant, dioecious or unisexual, borne singly or in threes in the leaf axils, are five- to six-petalled, white at first, changing to buff-yellow, 2.5–5 cm broad, and both sexes have central tufts of many stamens, though those of the female flowers with no viable pollen. The flowers also lack nectar. Male and female flowers appear on different plants (dioecious), and both sexes have to be planted in close proximity for fruit set. Bees are normally used by commercial orchards, although the more labour-intensive hand pollination is sometimes employed.
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The flowers are unisexual, the plants can be monoecious or dioecious. Male flowers form an interrupted spike or subcapitate inflorescence of glomeruled, ebracteate flowers. These consist of 4 basally connate perianth segments, that are ovate or elliptic, membranous and abaxially hairy; and 4 stamens with oblong anthers and linear, exserted filaments. Female flowers sitting single or paired axillary, enclosed by 2 hairy bracteoles, that are connate in the lower part, compressed to slightly keeled, with 4 hornlike tips; a perianth is missing, the female flowers consist just of an ovary with a short style and 2 elongated stigmas.
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Parietaria is a genus of flowering plants in the family Urticaceae, native to temperate and tropical regions across the world.Flora Europaea: ParietariaAfrican Flowering Plants Database: Parietaria (enter genus name in search box)Flora of North America: ParietariaFlora of China: ParietariaFlora of Pakistan: ParietariaAustralian Plant Name Index: Parietaria They are annual or perennial herbaceous plants growing to 20–80 cm tall, with green or pink stems. The leaves are alternate, simple, entire, often with a cluster of small leaves in their axils. Individual flowers are bisexual or unisexual, produced in clusters of three to many together in the leaf axils.
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P. monacha hybridises with Poeciliopsis lucida and Poeciliopsis occidentalis. When a female of P. monacha mates with a male of either of these two species, the offspring are invariably female. In fact this all-female breeding line can be maintained indefinitely in the laboratory by repeatedly back-crossing the offspring to males of P. lucida and P. occidentalis. In the headwaters of the Fuerte River in northwestern Mexico, it is found that only the bisexual form of P. monacha is present in the highest waters, and the proportion of unisexual individuals increases progressively downstream from here.
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Most Fraxinus species are dioecious, having male and female flowers on separate plants but sex in ash is expressed as a continuum between male and female individuals, dominated by unisexual trees. With age, ash may change their sexual function from predominantly male and hermaphrodite towards femaleness;Gender variation in ash (Fraxinus excelsior L.) Pierre Binggeli & James Power (1991) if grown as an ornamental and both sexes are present, ashes can cause a considerable litter problem with their seeds. Rowans or mountain ashes have leaves and buds superficially similar to those of true ashes, but belong to the unrelated genus Sorbus in the rose family.
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In the late 1970s, he was among the first to introduce mitochondrial (mt) DNA to population biology. This seminal work laid the foundation for phylogeography, a field for which he is recognized as the founding father. Among the many phylogeographic applications for which his laboratory paved the way were genetic assessments of marine and freshwater turtles, catadromous eels, unisexual fishes, and regional assemblages of birds, fishes, mammals, herps, and marine invertebrates. In the 1990s, Avise capitalized upon highly polymorphic microsatellite loci to analyze animal mating systems in nature, on creatures ranging from sea spiders and snails to polyembryonic armadillos to numerous fishes, including male-pregnant pipefishes and seahorses, and hermaphroditic killifishes.
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The flowers are unisexual, small (<1 cm long) and pale yellow in colour. They are thought to be pollinated by insects such as small bees and moths. On Barro Colorado Island (BCI), Panama, it tends to flower during the dry season from the end of January to the end of April, persisting for 11 to 15 weeks each year. In Costa Rica, it flowers slightly later, between March and July, peaking in April. Fruits form between 1 and 3 months after pollination occurs. The fruits are brightly colored green to purplish-black, approximately 17 mm long and contain large seeds (10–14 mm), they occur in groups of 3–5 drupes.
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Triops longicaudatus is usually greyish yellow or brown in color, and differs from many other species by the absence of the second maxilla. Apart from Triops cancriformis, it is the only tadpole shrimp species whose individuals display as many as three reproductive strategies: bisexual, unisexual (parthenogenetic), and hermaphroditic; see below. Triops cancriformis is easily recognizable by its yellow carapace with dark spots, whilst T. longicaudatus individuals have a uniform carapace. The species also appeared about 50 million years later, and, as its name suggests, its elongated tail structures (cercopods) are often nearly as long as the rest of the body; including the cercopods, the body may reach in length.
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Since the original description and early work on this species in the 1990s, other field work has revealed some instances of L. schismatica flowers that were unisexual. The closely related species Triuris brevistylis was discovered to be mostly dioecious but a few individuals were located that had bisexual flowers with the flower arrangement inverted, just like that of the normal L. schismatica flowers. This discovery led the authors of the study to conclude that the inverted floral morphology evolved before L. schismatica and T. brevistylis diverged. Isolated populations during the Quaternary Period (around five million years ago) when temperatures in the Lacandon lowland rainforest were six to eight °C (10.8 to 14.4 °F) cooler than today.
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Meliaceae, the mahogany family, is a flowering plant family of mostly trees and shrubs (and a few herbaceous plants, mangroves) in the order Sapindales. They are characterised by alternate, usually pinnate leaves without stipules, and by syncarpous,Of a gynoecium, made up of united carpels apparently bisexual (but actually mostly cryptically unisexual) flowers borne in panicles, cymes, spikes, or clusters. Most species are evergreen, but some are deciduous, either in the dry season or in winter. The family includes about 53 genera and about 600 known species, with a pantropical distribution; one genus (Toona) extends north into temperate China and south into southeast Australia, another (Synoum) into southeast Australia, and another (Melia) nearly as far north.
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Alternate leaves, petioles 3 to 12 mm long, oblong ovate to lanceolate ovate, with glands and hairs regularly distributed, undulate margins and softly serrated. Lamina 4 to 12 x 2,5 to 5 cm, pinnate veins, pilose and very notorious, mostly below the leaf, new borne green shoots pubescent with brown felt-like hairs. Flowers little unisexual: male in clusters of 3 flowers, briefly pedicellate, numerous stamens, male flowers disposed in 3 inflorescences supported by a peduncle about 1 cm long. Fruit made up by a cupule of 4 narrow valves, in its interior 2 to 3 little yellowish nuts 6 mm long, a little hairy, being the two lower triangular, tri-winged, and the flat internal, bi-winged.
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Leaves alternate, petiole 2–6 mm long,Enciclopedia de la Flora Chilena, 2008 leaves are elliptic-lanceolate 2–6 cm long and 1,5–3 cm wide, thick and leathery, apex and base are attenuate, irregularly toothed margins. Reddish and deciduous stipules. Flowers are hermaphrodite or unisexual, in groups of 2–3 in the axils; five sepals about 1 mm long; five petals wine colored in 2–3,5 mm, ovary reduced in male flowers with five stamens; in female, the ovoid ovary ends in a short style and this in its turn, in flat bi-lobed stigmas. Fruit capsule 6–8 long and 5 mm wide, two valves which contain 1 to 2 seeds.
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Ficus amplissima displays a syconium type of inflorescence (arrangement of the flowers on a plant) borne by all figs (genus Ficus), formed by an enlarged, fleshy, hollow receptacle with multiple ovaries on the inside surface. It is a monoecious species, meaning that separate staminate and carpellate flowers are always found on the same plant. Flowers are unisexual and arise with in the inner wall of syconia, are axillary (arising from the axil of an inflorescence) subsessile (not attached completely with a stalk) and have depressed globe-like shape (spherical with a flattened top and bottom). They are crowned towards the end of branchlets surrounded by basal bracts in a group of three.
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Another example is the one of competition for calling space in amphibians, where the calling activity of a species prevents the other one from calling in an area as wide as it would in allopatry. A last example is driving of bisexual rock lizards of genus Darevskia from their natural habitats by a daughter unisexual form; interference competition can be ruled out in this case, because parthenogenetic forms of the lizards never demonstrate aggressive behavior. This type of competition can also be observed in forests where large trees dominate the canopy and thus allow little light to reach smaller competitors living below. These interactions have important implications for the population dynamics and distribution of both species.
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Helophytes, rarely rheophytes, with thick creeping rhizome; leaf blade simple, ovate to almost linear, fine venation transverse-reticulate; spathe tube with connate margins; spadix entirely enclosed in spathe tube; flowers unisexual, perigone absent. Differs from Cryptocoryne in having female flowers spirally arranged (pseudo- whorl in Lagenandra nairii, whorled in Lagenandra gomezii) and free; spathe tube "kettle" with connate margins (containing spadix) occupying entire spathe tube; spathe blade usually opening only slightly by a straight or twisted slit; berries free, opening from base; leaf ptyxis involute.Simon J. Mayo, Josef Bogner, Peter C. Boyce: The Genera of Araceae. 1. published, Royal Botanic Gardens/ Kew Publishing, London 1997, (Full-text as PDF-file; Continental Printing, Belgium 1997).
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Two evolutionary pathways may be considered to explain how and why gynogenesis evolved. The single-step pathway involves multiple changes taking place simultaneously: meiosis must be interrupted, one gender's gametes eradicated, and a unisexual gender formation must arise. The second option involves multiple steps: a sexual generation is formed with a strongly biased sex ratio, and because of Haldane's Rule the species evolves towards loss of sexuality and selection that is preferential towards the gynogen. Experimenters who attempted unsuccessfully to induce P. formosa in a laboratory by hybridizing its genetic ancestors concluded that the evolutionary origin of P. formosa was not from the simple hybridization of two specific genomes, but the movement of certain alleles at certain loci that resulted in this evolutionary change to unisexuality.
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The fruit capsules of some varieties are more showy than the flowers. Male flower Pollen grains of Ricinus communis Female flower The green capsule dries and splits into three sections, forcibly ejecting seeds The flowers lack petals and are unisexual (male and female) where both types are borne on the same plant (monoecious) in terminal panicle-like inflorescences of green or, in some varieties, shades of red. The male flowers are numerous, yellowish-green with prominent creamy stamens; the female flowers, borne at the tips of the spikes, lie within the immature spiny capsules, are relatively few in number and have prominent red stigmas. The fruit is a spiny, greenish (to reddish-purple) capsule containing large, oval, shiny, bean-like, highly poisonous seeds with variable brownish mottling.
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Rock lizards are extremely rare on their own, usually forming settlements. The population density of parthenogenetic rock lizards can vary in a wider range than that of bisexual species: up to 200 individuals per 1 km of the route in unisexual species and up to 80 individuals in bisexual species, which is explained by the fact that parthenogenetic species are less aggressive and have a high population growth rate. Rock lizards are characterized by complex and diverse social systems, which, in particular, are characterized by stable long-term friendly relations between the male and the female and territorial or hierarchical relations between individuals of the same sex. The basis of the settlements of bisexual rock lizards are sedentary males and females with individual sites, often overlapping.
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Androgynous inflorescences usually with female flowers at proximal nodes and male flower at distal nodes. Flowers unisexual, apetalous, disc absent. Male flowers very small, shortly pedicellate, globose in bud; calyx parted into 4 small valvate sepals; stamens 4–8(–16) on a slightly raised receptacle, filaments free or basally connate; anthers with divaricate or pendulous thecae, unilocular, more or less elongated and later becoming vermiform; pollen grains oblate-spheroidal, with 3–5 pseudopores, tectate, psilate; pistillode absent. Female flowers generally sessile or subsessile, pedicellate in a few species; calyx of 3– (4–5) small sepals imbricate, connate at base; ovary of [1–2]3 carpels, surface often muricate, pubescent or papillose; ovules solitary in each cell, anatropes; styles reddish, free or basally connate, several times divided into filiform segment, rarely bifid or entire; staminodes absent.
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Gymnostoma australianum, also named the Daintree pine or oak, is a species of small trees which are (endemic) to a restricted area of the Daintree tropical rainforests region, of the larger region of the Wet Tropics of north-eastern Queensland, Australia. They constitute part of the plant family Casuarinaceae, often named she-oaks, members of which are characterised by drooping equisetoid (meaning "to look like Equisetum") evergreen foliage, and separate male and female flowers (unisexual). Superficially they look like well known scale–leaved gymnosperm trees species, such as Cupressus in the northern hemisphere and Callitris in the southern hemisphere. Within their restricted distribution in the Daintree rainforests region, they usually grow in the habitats of open, sunny, long-term rainforest gaps, ranging, from the lowlands to the uplands, in regularly flooded river bank (riparian) situations through to rocky or exposed, wet, cloudy, mountain top situations, including recorded collections from altitude.
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While it is often assumed that parthenogenesis is an inferior evolutionary strategy to sexual reproduction because parthenogenetic species lack the ability to complement genetic mutations through outcrossing or are unable to incorporate new genetic material, research on parthenogenetic species has gradually revealed a number of advantages to this mode of reproduction. Triploid unisexual geckos of the species Heteronotia binoei have greater endurance and aerobic capacity than their diploid ancestors, and this advantage may be the result of polyploidy and a form of hybrid vigor. It has also been observed that obligate parthenotes are often found at high altitudes and in sparse or marginal habitats, a pattern known as "geographical parthenogenesis," and their distribution in suboptimal territories may be a result of their increased colonization ability. A single parthenogenetic individual can colonize a new territory and produce offspring, while for a sexual species multiple individuals would need to occupy a new habitat and come into contact with each other for mating in order for successful colonization to occur.
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Laureliopsis philippiana is an evergreen tree up to 30 m (100 ft) tall and 1.4 m (55 in) in diameter, with thin bark, and aromatic wood, and a superficial resemblance to Bay Laurel. The leaves are aromatic, oblong, attenuate at the base, 4.9 long and 1.5–4 cm wide, glossy, leathery, the midrib with yellow hairs, the edges are heavily toothed in the two upper thirds, every tooth ends in a small point. The flowers are hermaphrodite or unisexual, they are small about 5–6 mm long, reddish-green, arranged in racemes, the peduncles are hairy about 2–3 mm long, flowers with bell-shaped perianth split in 7-9 petals more or less equal, hairy outside, 4 stamens and 8-20 staminodes, several carpels, the style is feathery with terminal stigma. The fruit is an achene almost oval, crowned by the perianth, about 1-1.3 cm long, formed by the perigonium that wraps several carpels, hairy, dark brown, spindle-shaped seeds, about 0.8-1.2 cm long, with the style covered by hairs about 5–6 mm long.
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