Dr Zhang and his colleagues have built an anuran cladogram—a family tree of 156 species of frog for which reasonably good data have been deposited in GenBank, the world's largest repository of DNA sequences.
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Itemirella is an extinct genus of prehistoric anuran of the Bissekty Formation, Uzbekistan.
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Paternal care occurs in a number of species of anuran amphibians, including glass frogs.
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Gastrophryne carolinensis belongs to one of the largest anuran families, the microhylids. No subspecies are currently recognized.
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Asexual phase in adult anuran host. The basic opaline life cycle begins with the large, multinucleate trophonts in the adult anuran cloaca. Through much of the year, the trophonts grow and divide continually to yield more trophonts. Nuclear divisions maintain the appropriate number of nuclei during this phase.
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Prosalirus bitis and the anuran caudopelvic mechanism. Journal of Vertebrate Paleontology 18(3):495–510.Curtis, K., and Padian, K. 1999.
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Ecology and Society, 14: art. 24 found a considerably negative effect on differing anuran species for areas of 250 to 1.000 meters.
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Anuran (frog) families represented are Bombinatoridae (1 species: Bombina maxima), Bufonidae, Dicroglossidae, Hylidae (1 species: Hyla annectans), Megophryidae, Microhylidae, Ranidae, and Rhacophoridae.
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The Kihansi spray toad is a small, sexually dimorphic anuran, with females reaching up to long and males up to . The toads display yellow skin coloration with brownish dorsolateral striping. They have webbed toes on their hind legs, but lack expanded toe tips. They lack external ears, but do possess normal anuran inner ear features, with the exception of tympanic membranes and air-filled middle ear cavities.
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Native predators may have adjusted to the ubiety of the toxic anuran through learning or as a result of evolutionary selective pressures applied by the invader.
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Bjerring, H. C. (2002). The anuran jaw apparatus in an evolutional light. Palaeontographica (A), 266, 93-119. organs and structures derived from the pharyngeal cleftsBjerring, H. C. (1989).
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Lacking a mouth, opalines feed by taking in nutrients from their surroundings by pinocytosis. While the opalines are often referred to as "parasites", two lines of evidence suggest that they are actually commensals which do no harm to their anuran hosts. # They are found almost exclusively in the large intestine and cloaca. Since the anuran absorbs the nutrients from its food in the small intestine, the opalines are probably not depriving their hosts of nutrients.
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Following the south-west monsoon rains that lash the Indian west coast from the first week of June, innumerable anuran species breed in ephemeral ponds and puddles.Saidapur S K(1989) Reproductive cycles of Amphibians; in Repriductive Cycles of Indian Vertebrates pp166-224 ed. S K Saidapur This incidentally puts the individuals in severe intra- and interspecific competition for food and space, and also to predation pressures. Microhabitat selection is, therefore, an important strategy employed by the anuran species including the bronzed frog.
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The specific name susurra is derived from the Latin susurrus meaning "whispering" and refers to the relatively quiet advertisement call of this species compared to those of other sympatric anuran (Hyla japonica and Rhacophorus arboreus).
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Mesozoic mammals from Arizona: new evidence in mammalian evolution. Science 222(4629):1233–1235.Jenkins, F. A., Jr. and Shubin, N. H. 1998. Prosalirus bitis and the anuran caudopelvic mechanism. Journal of Vertebrate Paleontology 18(3):495–510.
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In Hyla versicolor, females favor long calls rather than short callsWells, K. D. & Ryan, M. "The energetics of calling in frogs." Anuran communication. 45–60 (2001). while in Dendropsophus microcephalus they are attracted to short and high rate calling.
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PLOS ONE. 2016;11(3):e0151114. Its arms and legs splay out in the standard anuran body form. Compared to other frogs, N. sahyadrensis has a small head and an unusual pointed snout. Adults are typically dark purplish-grey in color.
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She studied reproductive strategies in the neotropical anuran community at Santa Cecilia, Ecuador and recognized ten different modes of reproduction. These categories were later modified and adapted for all anuran reproductive patterns that scientists are currently aware of. Crump was also a pioneer in classifying variability in amphibian egg size as a function of habitat predictability. Her research, focusing on tropical tree frogs, shows that in species that breed in temporary ponds, individual females produce clutches that have a greater range of egg sizes while those breeding in permanent ponds have a very concentrated distribution, rarely deviating from the mean.
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First report of Kaloula taprobanica Parker, 1934 from Rajasthan, along with updated list of anurans and their revised distribution in Rajasthan, India. JBNHS 109(3): 207-208.Mehra, S. P. (2010). Anuran diversity of southern Rajasthan with main emphasis on high altitude species.
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The Maya Mountains frog (Lithobates juliani) is a species of frog in the family Ranidae found in Belize and possibly Guatemala. Its natural habitats are subtropical or tropical moist lowland forests, moist savanna, and rivers. This anuran is endemic to the Belizean pine forests ecoregion.
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Vulcanobatrachus is an extinct genus of fossil frog. The new genus which contains the single species Vulcanobatrachus mandelai found at Marydale, South Africa was recently described.Trueb, L., Ross, C. F. and Smith, R. 2005. A New Pipoid Anuran From the Late Cretaceous of South Africa.
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It is believed that the opalines are simply living off the "left-over" nutrients in the feces, possibly supplemented by the biochemical contributions of the rich bacterial flora which also reside there. # Anuran hosts containing many thousands of opalines appear to be completely healthy, with no obvious irritation or other pathological signs on their intestinal or cloacal walls. Only about a dozen reports of opalines in fishes have been published, and even fewer on opalines from reptile or salamander hosts. Their scarcity outside of anuran hosts had led many to speculate that the others are just incidental infestations—maybe the infested snake had just eaten an infested frog, for example.
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Heyer, W. R., Donnelly, M. A., McDiarmid, R. W., Hayek, L. C., Foster, M. S. 1994. Measuring and monitoring biological diversity. Standard Methods for Amphibians. Smithsonian Institution Press, Washington and London Similarly, driving roads at night during anuran breeding times can yield a high diversity of species.
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Determining the size of the road-effect zone is additionally complicated by varying local spatial patterns and the result significantly depends on the particular species under investigation; for instance there are large differences between moose, mice, plants, bats or anurans, and even among anuran species themselves.
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Poyntonophrynus damaranus is a species of toad in the family Bufonidae. This species was previously known as Bufo damaranus, which is now considered a synonym. This anuran is endemic to Kaokoveld-Waterberg in area of northern and northwestern Namibia. The validity of this species has been questioned.
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Sexual and asexual phases in larval anuran host. Once cysts are eaten by foraging tadpoles, they excyst (hatch) to yield gamonts. The gamonts divide further, including a meiotic division, to yield haploid gametes. Each gamete has only one nucleus and may be either a microgamete or a macrogamete.
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This list of Anuran families shows all extant families of Anura. Anura is an order of animals in the class Amphibia that includes frogs and toads. More than 5,000 species are described in the order. The living anurans are typically divided into three suborders: Archaeobatrachia, Mesobatrachia, and Neobatrachia.
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Ecological Road-Effect Zone of a Massachusetts Suburban Highway. Conservation Biology, 14: 36-46 suggest an average area of 600 meters to be concerned, and Eigenbrod et al.Eigenbrod, F.; Hecnar, S.J. & Fahrig, L. 2009. Quantifying the road-effect zone: threshold effects of a motorway on anuran populations in Ontario, Canada.
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However, within pipids, Hymenochirus appears to be an exception, and sound production is based on moving air in a more conventional anuran manner. Nevertheless, molecular and morphological analyses show that sound production in Hymenochirus is an evolutionary novelty that represents a reversal to the ancestral condition of air-driven sound production.
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Su has studied the link between mating call and genetics in South-East Asian anuran (frog) populations and male and female courtship behaviour in jumping spiders. This research has shown that genetic links between certain courtship behaviours can be seen within in species, which has an impact on our understanding of evolution.
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White Lipped Tree Frog. The Animal Files The family Leptodactylidae, one of the most diverse anuran families, also has some very large members. The largest is the Surinam horned frog (Ceratophrys cornuta), which can reach in length from snout to vent and weigh up to .Surinam horned frog (Ceratophrys cornuta) – Videos Peru – Peru Videos. Bullafina.
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Anuran-dependent predation by the giant water bug, Lethocerus deyrollei (Hemiptera: Belostomatidae), in rice fields of Japan. Ecological Research 17(6): 655-661.Ohba, S. (2007). Notes on predators and their effect on the survivorship of the endangered giant water bug, Kirkaldyia (= Lethocerus) deyrolli (Heteroptera, Belostomatidae), in Japanese rice fields. Hydrobiologia 583(1): 377-381.
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Journal of Wildlife Diseases 38(3):593-603. The results of the study suggest that this fly is a facultative parasite of this frog and other amphibians. Previous records of L. silvarum parasitism in North America showed that myiasis is fatal to anuran hosts.Eaton, Brian R, Allisa E. Moenting, Cynthia A. Paszkowski and Danny Shpeley.2008.
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Pessier, AP, et al. (2014). Causes of Mortality in Anuran Amphibians From An Ex Situ Survival Assurance Colony in Panama. Zoo Biology 33 (6): 516-26. A stumbling block to the conservation of Agalychnis lemur at El Valle in Panama has been its tendency to develop a vitamin A defiency when given insect-based diets in captivity.
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Basal caecilians such as Ichthyophis go through a metamorphosis in which aquatic larva transition into fossorial adults, which involves a loss of the lateral line. More recently diverged caecilians (the Teresomata) do not undergo an ontogenetic niche shift of this sort and are in general fossorial throughout their lives. Thus, most caecilians do not undergo an anuran-like metamorphosis.
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Arenophryne xiphorhyncha, the southern sandhill frog, is a fossorial anuran found in a limited range of far western Australia. The only congener to A. xiphorhynca is the northern sandhill frog, Arenophryne rotunda, which was considered the sole species within the genus Arenophryne until this species was discovered about 100 kilometres from Geraldton, Western Australia, in Kalbarri National Park.
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The appearance of early jump recovery in more advanced taxa is a key innovation in anuran evolution. They are unusually small frogs, only in length. Most species lay their eggs in moist ground, typically under rocks or vegetation. After hatching, the tadpoles nest in the male's back, all without the need for standing or flowing water.
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Hochstetter's frog is named after the German geologist Ferdinand von Hochstetter. This species is endemic to New Zealand and belongs to the most primitive anuran suborder Archaeobatrachia, along with Archey's frog (Leiopelma archeyi), Hamilton's frog (L. hamiltoni), and the Maud Island frog (L. pakeka). Three species within the genus, L. auroraensis, L. markhami, and L. waitomoensis, are extinct.
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By far the most important clinical aspect of this species of fly is its causation of secondary myiasis in anuran hosts. Specifically, myiasis occurs when fly larvae, also known as maggots, infest living or necrotic tissue in either humans or animals. One case of myiasis was observed in wood frogs, Rana sylvatica, in southeastern Wisconsin.Bolek, Matthew G and John Janovy Jr.2002.
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Batrachochytrium salamandrivorans (Bsal) is a pathogenic chytrid fungus that infects amphibian species. salamanders and newts seem to be the most susceptible, however some anuran species are susceptible. Bsal has emerged recently and poses a major threat to species in Europe and North America. It was described in 2013 based on a strain collected from skin tissue of fire salamanders Salamandra salamandra.
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Reactive oxygen species (ROS) appear to be required for a regeneration response in the anuran larvae. ROS production is essential to activate the Wnt signaling pathway, which has been associated with regeneration in other systems. Limb regeneration in salamanders occurs in two major steps. First, adult cells de- differentiate into progenitor cells which will replace the tissues they are derived from.
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Davidson began conducting research as a teenager at The Marine Biological Laboratory. After graduating from high school, he matriculated to the University of Pennsylvania and graduated with a B.A. in biology in 1958. Davidson's Ph.D. work entailed studying RNA synthesis and gene expression in early development of the anuran Xenopus laevis in the lab of Alfred Mirsky at Rockefeller University.
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161x161px Tadpoles of frogs and toads are usually globular, with a laterally compressed tail and internal gills. When first hatched, anuran tadpoles have external gills that are eventually covered by skin. Newly hatched tadpoles are also equipped with a cement gland which allows them to attach to objects. The tadpoles have a cartilaginous skeletons and a notochord which eventually develops into a proper spinal cord.
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41(1): 13-20. but exceptionally large individuals can reach . Such giants are essentially unheard of today, although there are recent records of several individuals weighing . It is the largest anuran (frogs and toads) of the Americas, surpassing other large species like the Blomberg's, cane, Colorado River, cururu and smooth-sided toads, and the American bull-, Lake Junin, mountain chicken and Titicaca water frogs.
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59% of C. tomopterna clutches are often attacked by predators such as phorid flies (being the majorly responsible for clutch loss), and other unidentified predators. The reason for these clutch predations is mostly due to Anuran eggs being a high-protein energy source for many predators such as insects. They are especially notorious for larvae. Threats: Adult Predation Adult Callimedusa tomopternas are also highly predated on.
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Osgood's Ethiopian toad (Altiphrynoides osgoodi formerly known as Spinophrynoides osgoodi) is a possibly extinct species of toad in the family Bufonidae endemic to the mountains of south-central Ethiopia. It was named for the American biologist Wilfred Hudson Osgood who carried out fieldwork in Ethiopia for the Field Museum in 1926–27. He collected the original specimens of Osgood's Ethiopian toad and three other endemic species of anuran.
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Craugastor talamancae is a species of frog in the family Craugastoridae. This anuran is found in Costa Rica, Nicaragua, and Panama. Its natural habitats are subtropical or tropical moist lowland forests, subtropical or tropical moist montane forests, plantations, rural gardens, and heavily degraded former forest. According to accounts of J.M. Savage and of C. Michael Hogan, this frog is considered to have an altitudinal niche between 16 and 646 metres.
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Pristimantis moro was described by Jay M. Savage in 1965 as Eleutherodactylus moro. The specific name moro honors John Luther Mohr, a specialist in anuran enterofauna. The same species was described as Eleutherodactylus lehmanvalenciae by W. A. Thornton later in 1965, thus making it junior synonym of Eleutherodactylus moro. The specific name lehmanvalenciae honors Carlos Lehman Valencia, in recognition of "his many contributions furthering the knowledge of Colombian natural history".
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The Latin word Cranopsis has been used to name animal genera of frogs, mollusks and branchiopods. Cranopsis (Cope 1875), was used for an anuran, and is a junior homonym of Cranopsis (Adams 1860), for a mollusk; and Cranopsis (Dall 1871), for a branchiopod. Cranopsis currently describes a mollusk genus in the family Fissurellidae. The name was very briefly resurrected for a subgroup of toads (Bufo) by Frost et al. (2006a).
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The only other anuran in the habitat was what at the time was identified as Plectrohyla siopela, but later described as a new species, Plectrohyla celata. Sarcohyla cyanomma was once relatively common and conspicuous in its habitat. However, it was last collected in 1980, and is possibly now extinct. The stream at the type locality is still in good condition, so the decline might be caused by chytridiomycosis.
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As the host's breeding season approaches, the trophonts enter a phase known as palintomy -- a series of cell divisions with little or no overall growth or nuclear divisions. The resulting opalines, which become gradually smaller with fewer nuclei per individual, are called tomonts. At some point the small tomonts undergo encystment, and the cysts are released into the environment (i.e. the breeding pool of the anuran host) along with the feces.
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Oxyuroidea is composed on three families: Pharyngodonidae; parasites of herbivorous vertebrates, and Oxyuridae and Heteroxynematidae; parasites of mammals and some birds. The life cycle of G. batrachiensis is generally simple and direct. Adult worms live in the posterior gut of the aquatic larval stage, or tadpole, of an anuran host. The females of this species produce two types of eggs: thick-shelled eggs and thin-shelled eggs, which are produced in separate uteri.
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Most tadpoles have a flattened tail with which they swim by lateral undulation. Tadpoles have spiracles through which water exits the opercular chamber. Depending on the species, there can be two spiracles on both sides of the body, a single spiracle on the underside near the vent, or a single spiracle on the left side of the body. Metamorphosis of left Anuran tadpoles are usually herbivorous, feeding on soft decaying plant matter.
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Leptolalax tamdil is an anuran amphibian belonging to the family Megophryidae. It is so far reported only from Tam Dil lake, Mizoram, India. It is a small frog, but medium-sized among Leptolalax species; the male measuring 32.3 mm, and female 31.8 mm. The species is diagnosed with unique features such as eyelids with tubercles, distinct tympanum and supratympanic folds, undilated toe tips with dermal fringes, long hind limbs, and distinct color patches.
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Sex is genetically determined in amphibians. Temperature-induced sex reversal has been documented in some species of anuran and caudate amphibians. Temperature only can have an effect on sex differentiation during a window period called thermosensitive period (TSP) which varies among species. Tadpoles or larvae exposed to specific higher or lower temperatures, depending on the temperature thresholds of the species, can differentiate gonads that do not align with their primary sexual fate.
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The families within the mesobatrachian suborder generally contain morphological features typical of both the other suborders. For example, the palatine bone is absent in all archaeobatrachians, and present in all neobatrachians. However, within the mesobatrachians families, it can be dependent on the species as to whether the palatine bone is present. Due to the many morphological features which separate the frogs, many different systems are used for the classification of the anuran suborders.
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Small male and large female Fleay's barred frog (Mixophyes fleayi) in amplexus Male tusked frog Sexual dimorphism is seen as size difference between sexes in salamanders and in 90% of anuran species. Larger females is a result of selection for fecundity, including egg size or clutch size as they can store more energy and produce more offspring.Andersson, M. Sexual Selection. Princeton University Press (1994) as cited by Females are never more than twice the size of males.
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The terms beak and rostrum are also used to refer to a similar mouth part in some ornithischians, pterosaurs, turtles, cetaceans, dicynodonts, anuran tadpoles, monotremes (i.e. echidnas and platypuses, which have a beak- like structure), sirens, pufferfish, billfishes and cephalopods. Although beaks vary significantly in size, shape, color and texture, they share a similar underlying structure. Two bony projections—the upper and lower mandibles—are covered with a thin keratinized layer of epidermis known as the rhamphotheca.
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The Karpathos frog (Pelophylax cerigensis) is a species of frog in the family Ranidae. It is endemic to the island of Karpathos, South Aegean Sea, Greece. The Karpathos frog is considered the most endangered anuran amphibian in Europe because its range is restricted to two small rivers in the north part of the island. Its natural habitats are Mediterranean-type shrubby vegetation, rivers, intermittent rivers, freshwater lakes, intermittent freshwater lakes, freshwater marshes, intermittent freshwater marshes, arable land and ponds.
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At Freiburg Wiedersheim took part in a lengthy ongoing collaboration with Alexander Ecker and Ernst Gaupp to produce a comprehensive, illustrated atlas of anatomy for the European edible frog Rana esculenta. This collaboration took place over a 40-year period with several publications between 1864 and 1904 under the title Die Anatomie des FroschesEcker, A. Wiedersheim, R. Die Anatomie des Frosches. Braunschweig, Germany. 1864. and the resulting work is still considered a standard reference on anuran anatomy.
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About 88% of amphibian species are classified in the order Anura. These include over 7,100 species in 55 families, of which the Craugastoridae (850 spp.), Hylidae (724 spp.), Microhylidae (688 spp.), and Bufonidae (621 spp.) are the richest in species. European fire-bellied toad (Bombina bombina) The Anura include all modern frogs and any fossil species that fit within the anuran definition. The characteristics of anuran adults include: 9 or fewer presacral vertebrae, the presence of a urostyle formed of fused vertebrae, no tail, a long and forward- sloping ilium, shorter fore limbs than hind limbs, radius and ulna fused, tibia and fibula fused, elongated ankle bones, absence of a prefrontal bone, presence of a hyoid plate, a lower jaw without teeth (with the exception of Gastrotheca guentheri) consisting of three pairs of bones (angulosplenial, dentary, and mentomeckelian, with the last pair being absent in Pipoidea),Duellman, William E. an unsupported tongue, lymph spaces underneath the skin, and a muscle, the protractor lentis, attached to the lens of the eye.
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Hossini teaches at the University of Moulay Ismail, Faculté des Sciences in Meknes. She studied for her doctoral research in Paris, researching anuran species of the late oligocene and the miocene in France. Her work in Morocco includes the examination of cave deposits and examined amphibian remains from the Thomas Quarry Site, near Casablanca. Hossini identified for the first time the presence of the genus Baleaphryne for the first time in Africa at the Jebel Irhoud ("Ocre" quarry) site in Morocco.
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During the nighttime, the males are able to communicate to the females through vocal calls. During the nighttime is when they also search for food. The reproductive aspects reported for the species of this family are marked by the uniqueness of egg deposition, placed on green leaves hanging under standing water, where the tadpoles will complete their development. The lack of availability of sites for reproduction can lead to sites being shared by anuran species, which can sometimes lead to interspecific mating.
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Because amphibians are especially sensitive to environmental contamination, they are considered excellent indicators of the health of an ecosystem. Neotropic forests host the world's greatest diversity of anuran species. In Belize, amphibian populations remain largely undetermined due to their isolation and probable scarcity, and subsequently only fragmentary information is available on their status and distribution. From the mid-19th century, various scientific explorers such as Godman, Morelet and Salvin conducted herpetological research from samples collected in Belize and the surrounding Petén Basin.
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Males of the territorial breeding agile frog (Rana dalmatina), have a large variability in call characteristics and are able to discriminate between neighbouring and unfamiliar conspecifics. Calling is of the longest duration in response to an unfamiliar acoustic stimulus; in contrast, the response to a familiar conspecific call does not show any difference from solitary vocalisations.Lesbarrèresa, D. and Lodéa, T., (2002). Variations in male calls and responses to an unfamiliar advertisement call in a territorial breeding anuran, Rana dalmatina: evidence for a “dear enemy” effect.
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Fossils were found in the Sihetun locality of the western part of Liaoning province, in the lower part of the Yixian Formation, and date to approximately 124.6 Ma. Another specimen was collected near Heitizigou, south of Beipiao. The specimen has a snout–vent length of . Liaobatrachus is considered to be the most basal member of Discoglossidae based on phylogenetic analysis. As frogs are rarely found as articulated skeletons in the fossil record, the discovery of this new taxon has provided important insight into anuran evolution.
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Native to both South and Central America, Cane toads were introduced to Australia in the 1930s and have since become an invasive species and a threat to the continent's native predators and scavengers. The primary mechanism of impact cane toads have on Australian ecosystems is through poisoning of native species. The parotoid gland on either side of the head of a cane toad produces a secretion containing bufadienolides that is toxic to most animals. This chemical defence does not exist in any native Australian anuran.
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The anuran larva or tadpole has a single central respiratory spiracle and mouthparts consisting of keratinous beaks and denticles. Panamanian golden frog (Atelopus zeteki). Frogs and toads are broadly classified into three suborders: Archaeobatrachia, which includes four families of primitive frogs; Mesobatrachia, which includes five families of more evolutionary intermediate frogs; and Neobatrachia, by far the largest group, which contains the remaining families of modern frogs, including most common species throughout the world. The suborder Neobatrachia is further divided into the two superfamilies Hyloidea and Ranoidea.
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For example, in a single family, Megophryidae, length of late-stage tadpoles varies between and . The tadpoles of the paradoxical frog (Pseudis paradoxa) can reach up to , the longest of any frog, before shrinking to a mere snout-to-vent length of 3.4–7.6 cm (1.3–3.0 in). While most anuran tadpoles inhabit wetlands, ponds, vernal pools, and other small bodies of water with slow moving water, a few species are adapted to different environments. Some frogs have terrestrial tadpoles, such as the family Ranixalidae, whose tadpoles are found in wet crevices near streams.
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Allobates femoralis Bibron's toadlet Anuran mating systems are promiscuous: females and males breed with multiple mates and females exhibit sequential polyandry when one female is fertilized by more than one male at different times. Anurans are external fertilizers so there is no sperm competition. Polyandry has benefits for females such as fertility insurance, paternal care insurance and dispersal of mortality risk. Female anurans have a high risk of mating with sperm depleted males due to frequent mating and tend to select the same few males displaying fitness qualities.
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The majority of his scientific career has been spent studying the functional morphology and behavior of anuran larvae. He has published over 150 peer-reviewed papers on these animals. Wassersug’s more recent work focuses on prostate cancer and the psychology of androgen deprivation. Wassersug has received funding for his research from the Natural Sciences and Engineering Research Council, the Canadian Institutes of Health Research, Prostate Cancer Canada, the Prostate Cancer Foundation of British Columbia, Nova Scotia Health Research Foundation, the Canadian Space Agency, Parks Canada, and the Dalhousie Medical Research Foundation.
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This trait is possibly associated with early tetrapod evolution, which probably also appears on other members of this family and can act as a link to anuran tympanum evolution. The narrow head and elongated snout of Stanocephalosaurus suggests that stress levels during biting are slightly higher than temnospondyls with a wider and shorter skull. Its skull also has an elongated preorbital region compared to other mastodonsaurids. The vertebrae of Stanocephalosaurus are rhachitomous, with a neural arch and a bipartite centrum that is divided into a large, unpaired wedge-shaped intercentrum and smaller paired pleurocentra.
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Brachycephalus pitanga, the red pumpkin toadlet, is a small and brightly coloured species of anuran in the family Brachycephalidae. It is endemic to Atlantic rainforests in São Paulo state of southeastern Brazil, and only known from four localities at an altitude of in Ubatuba (the type locality) and São Luiz do Paraitinga. It can be very common where found, and two of the known localities are protected by the Serra do Mar State Park. Unlike many other pumpkin toadlets (genus Brachycephalus), the red pumpkin toadlet is not considered threatened.
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The brown banana frog (Afrixalus dorsalis), also known as the striped spiny reed frog, is an anuran in the family Hyperoliidae. It is found in Angola, Cameroon, Republic of the Congo, Democratic Republic of the Congo, Ivory Coast, Equatorial Guinea, Gabon, Ghana, Guinea, Liberia, Nigeria, Sierra Leone, and possibly Togo. Its natural habitats are subtropical or tropical moist lowland forests, subtropical or tropical moist shrubland, subtropical or tropical seasonally wet or flooded lowland grassland, freshwater marshes, intermittent freshwater marshes, rural gardens, heavily degraded former forest, ponds, seasonally flooded agricultural land, and canals and ditches.
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The male makes advertisement calls mostly at night, though it has been observed calling during the day as well. After mating, the female frog lays both fertilized eggs and trophic eggs at one time and then does not return to the nest. The tadpoles hatch and feed on the trophic eggs; they can remain in the nest for up to 25 days, growing in size. At the start of the rainy season, the tadpoles move to lentic water, where they will complete their metamorphosis, feeding on anuran eggs, other tadpoles, and carrion.
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Rhacophorus lateralis is an endangered rhacophorid tree frog endemic to the Western Ghats in South India. It has several common names: small tree frog, Boulenger's tree frog, small gliding frog, and winged gliding frog. After its original description in 1883 by George Albert Boulenger, the frog was rediscovered in Coorg in 2000 and has since been found in many parts of the Western Ghats around southern Karnataka and northern Kerala. Along with R. malabaricus, it is one of the few anuran amphibians in India that constructs its nest above the ground using leaves.
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Therefore, the invasion of cane toads constitutes a major threat to native anuran populations, especially ground-dwelling species which are most likely to come into contact with the toxic toad species. Australian marbled frogs have been found to exhibit rapid aversion learning, avoiding predation on edible-sized cane toads subsequently to a previous encounter with the toxic species. Toad-experienced native frogs most likely use both visual and olfactory cues to detect and avoid the toxic species. In particular, native Australian frog species have been found to avoid the urine scent of adult cane toads.
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Torresian crows appear to have developed a technique to kill and eat cane toads by flipping the toads on their backs and consuming only the internal organs and part of the thighs of the toxic anuran. It is possible that this predation behaviour is culturally transmitted. Torresian crows may learn how to perform the technique by imitating and replicating the behaviour of conspecifics. Predation on cane toads does not appear to be as common in wading birds, which are reluctant to prey on the toxic species in any of its ontological stages.
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Therefore, intraspecific variance in gape size, and hence in the likelihood consuming a lethal dose of toxin, induces a strong selective pressure for snakes with smaller gape sizes. Data collected over 80 years from red-bellied black snakes and common tree snakes, shows that the body length of these toad-vulnerable species increases with time since exposure to the toxic anuran. Correspondingly, gape size decreases with increasing body length. Conversely, species at a lower risk from cane toads, including the marsh snake and the keelback snake, show no significant morphological variation over time.
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As a generalized system, Gosner stages may not be adequate for describing development of some anuran tadpoles. For example, in the torrent-dwelling tadpoles of Ansonia longidigita and Meristogenys orphnocnemis, the usual Gosner stages become inappropriate beyond the stage 41 because the tadpoles retain their oral disc longer than the system depicts. This is interpreted as an adaptation that allows the tadpoles to cling to the rocks until the tail is almost fully resorbed. In Limnonectes limborgi, the tadpoles are free-living but non-feeding ("nidicolous") and retain their yolk sac until stage 37, at least.
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While olfactory cues are considered a secondary emergence stimulus, there is evidence in other anurans that the smell of emergent plant growth can also guide frogs to breeding sites, specifically pond weed species. Persistent emergent behaviour has been observed personally when a piece of moss was placed in an enclosure of two captive Spea bombifrons. Anuran tadpoles almost always have evidence of neuromasts arranged in lateral lines, although these only exist in adults of fully aquatic species, of which there are surprisingly few. There is poor research on how tadpoles use this sensory input during development.
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The Neobatrachia (New Latin neo- ("new") + batrachia ("frogs")) are a suborder of the Anura, the order of frogs and toads. This suborder is the most advanced and apomorphic of the three anuran suborders alive today, hence its name, which literally means "new frogs" (from the hellenic words neo, meaning "new" and batrachia, meaning "frogs"). It is also by far the largest of the three; its more than 5,000 different species make up over 96% of all living anurans. The differentiation between Archaeobatrachia, Mesobatrachia, and Neobatrachia is based primarily on anatomic differences, especially the skeletal structure, as well as several visible characteristics and behaviors.
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The process of multi-modal signaling is believed to help facilitate the courtship process in many species. One such species in which multi-modal signaling is seen to improve mating success is the green tree frog (Hyla cinerea). Many anuran amphibians, such as the green tree frog, may use visual cues as well as auditory signals to increase their chances of impressing a mate. When the calls of the tree frogs were held equal, it was determined that females tended to overlook an auditory-only stimulus in favor of males who combined auditory/visual multi- modal signals.
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Two major hormones have been identified to be involved in amplexus. The hormone arginine vasotocin (AVT) has been identified as having an effect on the calling behaviours produced by these male amphibians when searching for a female mate, as AVT increased the amount of calling behaviour produced in male amphibians. Additionally, it is believed that the gonadotropin-releasing hormone (GnRH) has an influence on amplexus in amphibians, as it has been found to produce or initiate this behaviour in many anuran amphibians. Furthermore, both arginine vasotocin and gonadotropin-releasing hormone have been found to be involved in the sexual behaviour of male amphibians.
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The tibia and fibula bones are also separate, making it probable that Triadobatrachus was not an efficient leaper. The earliest known "true frogs" that fall into the anuran lineage proper all lived in the early Jurassic period. One such early frog species, Prosalirus bitis, was discovered in 1995 in the Kayenta Formation of Arizona and dates back to the Early Jurassic epoch (199.6 to 175 million years ago), making Prosalirus somewhat more recent than Triadobatrachus. Like the latter, Prosalirus did not have greatly enlarged legs, but had the typical three-pronged pelvic structure of modern frogs.
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Insect predators of western honey bees include the Asian giant hornet and other wasps, robber flies, dragonflies such as the green darner, some praying mantises, water striders and the European beewolf. Arachnid predators of western honey bees include fishing spiders, lynx spiders, goldenrod spiders and St. Andrew's cross spiders. Reptile and amphibian predators of western honey bees include the black girdled lizard, anoles, and other lizards, and various anuran amphibians including the American toad, the American bullfrog and the wood frog. Specialist bird predators of western honey bees include the bee-eaters; other birds that may take western honey bees include grackles, hummingbirds, tyrant flycatchers and the summer tanager.
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The Stanocephalosaurus have at least 100 straight and conical teeth on the premaxilla and maxilla combined, gradually increasing in size towards the front. Other skull regions previously inaccessible or too poorly preserved on the Stanocephalosaurus have been observed with X-ray micro-CT scans, including the otic capsule, delta groove of the exoccipital, as well as parts of the arterial and nervous system. Air pockets around the stapes of Stanocephalosaurus have been hypothesized to act as resonance chambers, meaning that the spoon-shaped inner ear bone could be related to underwater hearing. This trait is possibly associated with early tetrapod evolution, and can act as a link to Anuran tympanum evolution.
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Pregnancy testing was conducted in the mid-20th century by injecting urine from a woman into a male toad's lymph sacs, and if spermatozoa appeared in the toad's urine, the patient was deemed to be pregnant. The tests using toads were faster than those employing mammals; the toads were easier to raise, and, although the initial 1948 discovery employed Bufo arenarum for the tests, it soon became clear that a variety of anuran species were suitable, including the cane toad. As a result, toads were employed in this task for around 20 years. As a laboratory animal, the cane toad is regarded as ideal; they are plentiful, and easy and inexpensive to maintain and handle.
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Based on the similarities between lens and cornea, such as abundant water-soluble enzymes, and being derived from ectoderm, the lens and cornea are thought to be co-evolved as a "refraction unit." Gene sharing would maximize light transmission and refraction to the retina by this refraction unit. Studies have shown that many water-soluble enzymes/proteins expressed by cornea are identical to taxon-specific lens crystallins, such as ALDH1A1/ η-crystallin, α-enolase/τ-crystallin, and lactic dehydrogenase/ -crystallin. Also, the anuran corneal epithelium, which can transdifferentiate to regenerate the lens, abundantly expresses ubiquitous lens crystallins, α, β and γ, in addition to the taxon-specific crystallin α-enolase/τ-crystallin.
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Kayentachelys was initially interpreted as an aquatic turtle, based upon the sharp tapered edges of the low-domed shell and the lack of both limb armor and sculpturing on the carapace. Kayentachelys is one component of a diverse assemblage of vertebrate taxa preserved within the Kayenta Formation. Kayentachelys lived alongside hybodontoid chondrichthyans; the early anuran Prosalirus; the gymnophionan Eocaecilia; sphenodontid diapsids; several species of crocodylomorph, including Kayentasuchus, Eopneumatosuchus, Protosuchus, and the goniopholidid Calsoyasuchus; the pterosaur Rhamphinion; the sauropodomorph dinosaur Sarahsaurus; the theropod dinosaurs Dilophosaurus and "Syntarsus" kayentakatae; the ornithischian dinosaur Scutellosaurus; the tritylodontid synapsids Oligokyphus, Dinnebitodon, and Kayentatherium; the mammaliaform synapsid Dinnetherium; and several other yet-unnamed taxa. The paleoenvironment of the Kayenta Formation in which Kayentachelys lived has been reconstructed as a floodplain drained by low-energy, sediment-rich streams.
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The UV-B radiation theory, which suggests that the decline in golden toads resulted from an increase in UV-B radiation, has little evidence supporting it because there was no high elevation UV-B radiation recorded, also, there is little evidence that an increase in UV-B radiation would have an effect on anurans. Another theory is that the anuran water loss from dry conditions helped cause high mortality rates among adults, although this point is hotly contested. In 1991, ML Crump, FR Hensley, and KL Clark attempted to understand whether the decline of the golden toad in Costa Rica meant that the species was underground or extinct. They found that each year from the early 1970s–1987 golden toads emerged from retreats to breed during April–June.
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Amphibians such as the Axolotl are also known to deliberately ingest rocks that are presumed to be gastroliths.Kulbisky et al The axolotl as an animal model for the comparison of 3-D ultrasound with plain film radiography rrr in Medicine and Biology, July 1999 Volume 25, Issue 6, Pages 969–975Wings, O A review of gastrolith function with implications for fossil vertebrates and a revised classification Acta Palaeontologica Polonica 52 (1): 1–16 Apparent microgastroliths have also been found in frog tadpoles.Wickramasinghe, DD et al Ontogenetic changes in diet and intestinal morphology in semi-terrestrial tadpoles of Nannophrys ceylonensis (Dicroglossidae) Copeia, Vol2007, Iss 4 (Dec 2007) Ingestion of silt and gravel by tadpoles of various anuran (frog) species has been observed to improve buoyancy control.Rondeau, et al Larval Anurans Adjust Buoyancy in Response to Substrate Ingestion Copeia: February 2005, Vol.
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He also served as a visiting scientist at the National Institute for Basic Biology, Japan and had two short stints in Germany at Ruhr University Bochum in 1995 and University of Würzburg in 2004 as an INSA-DFG Exchange Program fellow of the Indian National Science Academy and Deutsche Forschungsgemeinschaft (DFG). Focusing his researches on comparative endocrinology of amphibians, Saidapur explained the different types of reproductive processes followed by the tropical anurans and their control mechanisms. His studies are reported to have widened the understanding of the reproductive biology of the vertebrates and concentrating his researches on Indian Bullfrog, he proposed gametogenesis methodologies for producing frogs of predetermined sex. His studies also covered the behavioral ecology of anuran tadpoles and agamid lizards with regard to their foraging techniques, food identification, kin detection and predator-prey relationships and he developed new ways for the captive breeding of reptiles.
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