244 Sentences With "hydroid" | Random Sentence Generator

The slug, a gaudily colored species of nudibranch, uses hydroid colonies for shelter.

When a hydroid captured plankton prey, the attack rate on the hydroids by the nudibranchs doubled.

Offered a choice of brine shrimp and hydroid polyps (small coral-like organisms), the slugs opted for polyps that had swallowed the shrimp—a clever caloric twofer.

"The strong behavioral response of the nudibranch to fed hydroid colonies in the prey choice experiment suggests that nudibranchs will, by preference, consume hydranths that have captured and are handling prey," the researchers wrote.

Cordylophora caspia (or freshwater hydroid) is a species of athecate hydroid in the family Cordylophoridae.

Hydroid dermatitis is a cutaneous condition that occurs after contact with the small marine hydroid Halecium.

Candelabrum tentaculatum, also called the dreadlocks hydroid or calamari hydroid, is a sessile marine hydroid, that is found off the Cape Peninsula of South Africa.Millard, N.A.H. 1975. Monograph on the Hydroida of Southern Africa. Ann. S. Afr. Mus.

Eudendrium ramosum, sometimes known as the tree hydroid, is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae of the order Anthoathecata.

The tubular hydroid (Ectopleura crocea) is a species of hydroid cnidarian, and is found in temperate coastal waters. It is a member of the family Tubulariidae.

Eubranchus prietoi was found with the hydroid Plumularia setacea, which is presumed to be its food. It lays short egg coils across the midrib of the hydroid.

Trinchesia kuiteri feeds on the sponge associated solitary hydroid Zyzzyzus spongicola. In a remarkable adaptation the cerata have tentacle-like filaments which mimic the tentacles of the hydroid.

The tubular sponge hydroid (Zyzzyzus warreni) is a species of hydroid cnidarian. It is a member of the family Tubulariidae. These animals usually grow embedded in sponges.Millard, N.A.H. 1975.

Candelabrum capensis, or gnome's hat hydroid, is a species of sessile hydroid cnidarian. It is a member of the family Candelabridae.Millard, N.A.H. 1975. Monograph on the Hydroida of Southern Africa. Ann.

The diet of this species is a hydroid, Tubularia indivisa.

Doto greenamyeri is found on colonies of an aglaopheniid hydroid.

Zelentia pustulata feeds on the hydroid Halecium muricatum, family Haleciidae.

Doto floridicola feeds on the hydroid Aglaophenia kirchenpaueri, family Aglaopheniidae.

Doto millbayana feeds on the hydroid Plumularia setacea, family Plumulariidae.

Cuthonella concinna feeds on the hydroid Sertularia argentea, family Sertulariidae.

Doto onusta feeds on the hydroid Dynamena pumila, family Sertulariidae.

Doto lancei feeds on the hydroid Aglaophenia sp., family Aglaopheniidae.

Doto hystrix feeds on the hydroid Schizotricha frutescens, family Halopterididae.

Doto lemchei feeds on the hydroid Aglaophenia tuberculata, family Aglaopheniidae.

Doto koenneckeri feeds on the hydroid Aglaophenia pluma, family Aglaopheniidae.

Kabeiro phasmida is found on colonies of a pinnate hydroid.

Doto eireana feeds on the hydroid Amphisbetia operculata, family Sertulariidae.

Doto tuberculata feeds on the hydroid Sertularella gayi, family Sertulariidae.

Doto maculata feeds on the hydroid Halopteris catharina, family Halopterididae.

Tenellia diversicolor feeds on a hydroid, a species of Aglaophenia, family Aglaopheniidae.

Such polyp dimorphism has been reported in three other species of hydroid.

Ectopleura larynx, or ringed tubularia, is a hydroid in the family Tubulariidae.

Coryne eximia is a species of athecate hydroid belonging to the family Corynidae.

Species of hydroid are sometimes found growing on the mollusc shells occupied by hermit crabs. In one such case, a colony of Schuchertinia milleri was found on the shell occupied by the whiteknee hermit crab Pagurus dalli (which is more usually overgrown by a species of sponge). The association seems to be symbiotic, with the crab benefitting from the protection provided by the hydroid with its stinging cells, and with the hydroid benefitting avoiding being buried in the sediment, and by being transported to new feeding locations. The crab has been observed, when "wearing" other species of hydroid, to wipe the flagellum of its second antenna across the surface of the hydroid colony, in order to gather larger planktonic prey items from its epibiont.

Bougainvillia muscus is a marine invertebrate, a species of hydroid in the suborder Anthomedusae.

Bougainvillia britannica is a marine invertebrate, a species of hydroid in the suborder Anthomedusae.

Eudendrium moulouyensis is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium minutum is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium merulum is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium maorianus is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium maldivense is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium magnificum is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium macquariensis is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium laxum is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium mucronatum is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium nambuccense is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium nodosum is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium novazealandiae is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium parvum is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium carneum is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium cingulatum is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium currumbense is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium cyathiferum is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium deciduum is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium deforme is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium capillare is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium californicum is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium calceolatum is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium centicaule is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium caraiuru is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium capillaroides is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium cnidoferum is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium cochleatum is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium corrugatum is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium fruticosum is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium garis is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium generale is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium glomeratum is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium imperiale is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium infundibuliforme is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium irregulare is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium jaederholmi is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium japonicum is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium kirkpatricki is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium klausi is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium distichum is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium exiguum is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium eximium is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium album is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium balei is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium aylingae is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium attenuatum is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium armatum is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium armstongi is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium bathyalis is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium bermudense is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium boreale is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium biseriale is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium arbuscula is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium breve is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium pocaruquarum is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium rugosum is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium sagaminum is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium scotti is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium terranovae is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium pennycuikae is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium rameum is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium ritchiei is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium simplex is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium speciosum is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium tottoni is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium vaginatum is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Eudendrium vervoorti is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Schuchertinia milleri, commonly known as the Miller hydractinia, hedgehog hydroid or snail fur, is a small colonial hydroid in the family Hydractiniidae, found in the eastern Pacific Ocean. It forms mat-like colonies on rocks, or sometimes on the mollusc shells occupied by hermit crabs.

Colony Pennaria disticha, also known as the Christmas tree hydroid, is a species of athecate hydroid in the family Pennariidae. Colonies are common in the Mediterranean Sea growing on rocks close to the surface. This species has been used in research into prey capture.

Hydroid species Bougainvillia aberrans distribute from shallow water to deep sea in the Bermuda area. Calder, D. R. (1998). Hydroid diversity and species composition along a gradient from shallow waters to deep sea around Bermuda. Deep Sea Research Part I: Oceanographic Research Papers, 45(11), 1843–1860.

The influence of the epizoic hydroid Hydractinia angusta on the recruitment of the Antarctic scallop Adamussium colbecki.

Minimum recorded depth is 1 m. Maximum recorded depth is 4.5 m. Lomanotus vermiformis feeds on the common stinging hydroid Lytocarpus philippinus and on hydroids of the genus Macrorhynchia. It was also found feeding on an unidentified species of hydroid in Panama, on which it is extremely cryptic.

Sertularella polyzonias is a branching colonial hydroid in the family Sertulariidae.WoRMS (2004). Sertularella polyzonias. In: Schuchert, P. (2017).

Catriona tema was found on the sea shore at low water on the hydroid Pennaria disticha, family Pennariidae.

MacFarland reports that this nudibranch feeds on the hydroid Hydractinia, which grows on the holdfasts of Cystoseira osmundacea.

Jellyfish exhibits both asexual and sexual reproduction by budding during hydroid stage and releasing gametes in medusae stages.

Differences between epilithic and epizoic hydroid assemblages from commercial scallop grounds in the Bay of Fundy, northwest Atlantic.

American zoologist and curator Eudendrium dispar is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae.

Feeds on the hydroid Tubularia larynx. Individuals are thought to feed by eating through the stems of the hydroid rather than on the polyps. Usually found in exposed places, in strong tidal streams, and in shallow water, from 0 m to 20 m depth. The spawn consists of lozenge-shaped packets of eggs.

Sertularella gayi is a branching colonial hydroid in the family Sertulariidae.WoRMS (2017). Sertularella gayi (Lamouroux, 1821). In: Schuchert, P. (2017).

Doto columbiana feeds on the hydroid Aglaophenia sp., family Aglaopheniidae.McDonald, G., (2015). Intertidal Invertebrates of the Monterey Bay Area, California.

Sea anemone dermatitis is a cutaneous condition similar to jellyfish and hydroid dermatitis, caused by contact with certain sea anemones.

Sertularella acutidentata is a branching colonial hydroid in the family Sertulariidae.Schuchert, P. (2018). World Hydrozoa Database. Sertularella acutidentata Billard, 1919.

Sertularella crassa is a branching colonial hydroid in the family Sertulariidae.Schuchert, P. (2018). World Hydrozoa Database. Sertularella crassa Billard, 1919.

Sertularella decipiens is a branching colonial hydroid in the family Sertulariidae.Schuchert, P. (2018). World Hydrozoa Database. Sertularella decipiens Billard, 1919.

Sertularella inconstans is a branching colonial hydroid in the family Sertulariidae.Schuchert, P. (2018). World Hydrozoa Database. Sertularella inconstans Billard, 1919.

The gnome's hat hydroid grows to about 3 cm tall. It is a small conical hydroid with 30-40 adhesive knobs at its base. The cone is made up of 400-600 densely packed warty tentacles which contain the stinging cells. Its colour is variable, from a purple-brown to magenta or pale pink.

Furthermore, the perisarc of B. aberrans is clear and not covered with mud or sand. The latest B. aberrans eggs are surrounded by envelopes with tiny heterotrchous microbasic eurytele nematocysts. The exoskeleton of Hydroid and Bougainvillidae family starts as epidermal secretions. Coenosarc, which is the epithelial epidermal layer consists of various cell types of Hydroid.

Coryne muscoides is a species of athecate hydroid belonging to the family Corynidae. It is a species of the north-eastern Atlantic Ocean and the Mediterranean Sea. This is a many-branched rose-coloured hydroid, up to 15 cm tall with distinctive ringed stems and branches. Each branch ends with a cluster of knobbed tentacles.

A study showed that its larvae preferentially settled in the vicinity of other epibionts, usually on scallop shells, and that the scallop larvae were deterred from settling in the vicinity of colonies of the hydroid. It is surmised that the hydroid benefits from a solid substrate on which to live, and although the scallop benefits from the protection from predators provided by the stinging cells of the hydroid, it is disadvantaged by the failure of its larvae to establish themselves in their preferred location, on the shells of mature scallops.

The tessellated blenny lives inside an empty shell of the large barnacle, Megabalanus tintinnabulum. It is dioecious and the male and female form a pair bond. Fertilisation is external and the male broods a clump of eggs inside the barnacle shell. There is also an association with the hydroid ', this species preferring areas where the hydroid is abundant.

The B. muscus hydroid buds and forms medusae by asexual reproduction. When these mature, sexual reproduction occurs, the fertilised eggs settle out and new hydroids are formed. The hydroid grows rapidly and may starts to produce medusae when as little as seven weeks old. The medusae grow on the side branches and become free swimming when they are released.

Bougainvillia crassa is a marine invertebrate, a species of hydroid in the suborder Anthomedusae. It was first described by Frassa in 1938.

Minimum recorded depth is 20 m. Maximum recorded depth is 20 m. Doto cabecar feeds on the hydroid, Thyroscyphus marginatus (family Sertulariidae).

Doto rosea has been reported to feed on colonies of the hydroid, Eudendrium sp. (family Eudendriidae).Opisthobranchia des Mittelmeeres. Nudibranchia und Saccoglossa.

The eggs are laid in small groups of capsules which resemble stalked clubs. The commensal hydroid deters several of the snail's predators.

Bougainvillia frondosa is a marine invertebrate, a species of hydroid in the suborder Anthomedusae. It was first described by Mayer in 1900.

Sertularella ellisii is a branching colonial hydroid in the family Sertulariidae.Schuchert, P. (2018). World Hydrozoa Database. Sertularella ellisii (Deshayes & Milne Edwards, 1836).

This sea slug is known to rapidly devour hydroid colonies. Tenellia adspersa is a carnivore feeding primarily on hydroids such as Cordylophora caspia.

Feeds on the hydroid Hydractinia echinata.Picton, B.E. & Morrow, C.C. (2015). Cuthona nana (Alder & Hancock, 1842).[In] Encyclopedia of Marine Life of Britain and Ireland.

I. Lobyshev. Activating influence of heavy water of small concentration on the regeneration of hydroid polip Obelia Geniculata. Biofizika 28, 666 (1983) and 1990s,G.

Minimum recorded depth is 0 m. Maximum recorded depth is 20 m. This species usually feeds on Eudendrium arbuscula, a hydroid in the family Eudendriidae.

J. falcata feeds generally on hydroid growth on the bottom of rafts and ships. It is generally a suspension feeder normally found on sediment areas.

Diaphoreolis lagunae feeds on the hydroid Sertularella turgida, family Sertulariidae.Rudman, W.B. (2000) (July 10) Cuthona lagunae (O'Donoghue, 1926). [In] Sea Slug Forum. Australian Museum, Sydney.

Hyastenus borradaile, commonly called White-v hydroid spider crab, is a small crustacean belonging to the Epialtidae family. It is native to the Indo- Pacific.

This species feeds preferentially on the hydroid Thuiaria argentea in the family Sertulariidae. Dendronotus albus is said to prefer Abietinaria greenei, Hydrallmania distans and Abietinaria amphora.

Minimum recorded depth is 9 m. Maximum recorded depth is 9 m. Doto kekoldi is found associated with the hydroid Eudendrium sp. which is presumably its prey.

The B. britannica hydroid buds and forms medusae by asexual reproduction. When these mature, sexual reproduction occurs, the fertilised eggs settle out and new hydroids are formed.

Hydractinia echinata is a colonial marine hydroid which is often found growing on dead, hermit-crabbed shells of marine gastropod species. This hydroid species is also commonly known as snail fur, a name which refers to the furry appearance that the hydroids give to a shell. In the northwestern Atlantic, these hydroids are especially common on the outside of shells that are occupied by the flat-clawed hermit crab.

Bougainvillia aberrans consists of the hydroid colony with soft curly perisarc polysiphonic hydrocaulus, hydranths including 16 tentacles maximum, and medusa buds. Hydroid is part of the Cnidaria phylum. So, B. aberrans are radial symmetry, that they have cnidae that are unique sting structures unique to this phylum. Bougainvillia aberrans is different from other hydranths species because B. abberans have a lengthy spindled manubrium, negligible tentacles, and survive for a short period.

Doto paulinae has been reported to feed on colonies of the hydroid, Obelia geniculata (family Campanulariidae).Schmekel, L. and Portmann, A., 1982. Opisthobranchia des Mittelmeeres. Nudibranchia und Saccoglossa.

Hundreds of different AUVs have been designed over the past 50 or so years, but only a few companies sell vehicles in any significant numbers. There are around 10 companies that sell AUVs on the international market, including Kongsberg Maritime, Hydroid (now a wholly owned subsidiary of Kongsberg Maritime"KONGSBERG acquires Hydroid LLC" Kongsberg - Hydroid, 2007), Bluefin Robotics, Teledyne Gavia (previously known as Hafmynd), International Submarine Engineering (ISE) Ltd, Atlas Elektronik, and OceanScan. Vehicles range in size from man portable lightweight AUVs to large diameter vehicles of over 10 metres length. Large vehicles have advantages in terms of endurance and sensor payload capacity; smaller vehicles benefit significantly from lower logistics (for example: support vessel footprint; launch and recovery systems).

After the hydroid has dissolved the shell its semi-calcareous matted structure acts as a substitute. Being encrusted by a hydroid colony seems to deter predation by octopuses. Pagurus dalli is one of several species of hermit crabs in the infraorder Anomura that the parasitic barnacle Clistosaccus paguri uses as a host. A female cyprid larva of the parasite injects some cells into the crab's abdomen at any stage in the crab's moulting cycle.

This species feeds on the hydroid Aglaophenia.Behrens, D. W., & Hermosillo, A. (2005) Eastern Pacific nudibranchs, a guide to the opisthobranchs from Alaska to Central America. vi + 137 pp., 314 photos.

The mouth is surrounded by a ring of gonozooids and dactylozooids. Tentacles are only found on the dactylozooids, which exist furthest away from the mouth, towards the outer part of the hydroid colony.

Tenellia punicea feeds on a large purple athecate hydroid which is thought to be an undescribed species of Corymorpha.Rudman, W.B. (2003) (October 19) Cuthona punicea Millen, 1986. [In] Sea Slug Forum. Australian Museum, Sydney.

Halecium muricatum, commonly known as the sea hedgehog hydroid, is a species of hydrozoan in the family Haleciidae. It occurs mainly in arctic and northern temperate waters, in both the Atlantic and Pacific Oceans.

Halecium halecinum, commonly known as the herring-bone hydroid, is a species of hydrozoan in the family Haleciidae. It is native to the eastern Atlantic Ocean, the western Atlantic Ocean and the eastern Pacific Ocean.

Tubularia indivisa, or oaten pipes hydroid, is a species of large hydroid native to the northeastern Atlantic Ocean, the North Sea, Norwegian Sea, and the English Channel. The conical solitary polyps are found on dull yellow unbranched stems that reach in height with a diameter of . They may be fused to a small number of other individual stems at their bases. The pinkish to red polyps resemble flowers, having two concentric rings of tentacles, with the outer rings being paler and longer than the inner ring.

Facelina annulicornis is a predator of the hydroid Halecium halecium and probably other hydroids and possibly other aeolid nudibranchs.Picton, B.E. & Morrow, C.C., 2010. Facelina annulicornis (Chamisso & Eysenhardt, 1821).[In] Encyclopedia of Marine Life of Britain and Ireland.

This species was described from Naples, Italy, in the Mediterranean Sea. The 3.5 mm long holotype was collected on the hydroid Obelia geniculata, which was growing on the sea grass Posidonia at 10m depth off Capo Posillipo.

Bougainvillia superciliaris is a marine invertebrate, a species of athecate hydroid. It belongs to the Bougainvillidae family. It can be confused with Rathkea octopunctata, but differs from it in four bundles of tentacles of the outer circle.

The hydroid form is usually colonial, with multiple polyps connected by tubelike hydrocauli. The hollow cavity in the middle of the polyp extends into the associated hydrocaulus, so that all the individuals of the colony are intimately connected. Where the hydrocaulus runs along the substrate, it forms a horizontal root-like stolon that anchors the colony to the bottom. The hydroid Tubularia indivisa, fertile, Gulen Dive resort, Norway The colonies are generally small, no more than a few centimeters across, but some in Siphonophorae can reach sizes of several meters.

It also feeds on detritus and plankton. In the United Kingdom, it lives almost exclusively on the oaten pipes hydroid (Tubularia indivisa) whilst the juveniles have a wider diet range.Picton, B.E. & Morrow, C.C. (2015). Coryphella rufibranchialis (Johnston, 1832).

Most hydrozoan species include both a polypoid and a medusoid stage in their lifecycles, although a number of them have only one or the other. For example, Hydra has no medusoid stage, while Liriope lacks the hydroid stage.

Bougainvillia aberrans n. sp. has holotype and paratype. Also, medusae of B. aberrans appear sexually mature and relatively short-lived for release from the hydroid. It is different from the reduced Medusa buds with its blunt marginal tentacles.

William James Rees (1913–1967) was a British hydroid and cephalopod researcher at the Natural History Museum in London.Crawford, G.I. 1968. Obituary: W. J. Rees, D.Sc., 1913–1967. Proceedings of the Malacological Society of London 38(2): 103–106.

Solanderia is known from its polyp or hydroid stage, and produces gonophores which release sperm and eggs for reproduction. Where known, the gonophores are cryptomedusoid or eumedusoid, arising directly from the coenosarc.Pallas, P.S. (1766) Elenchus zoophytorum. Van Cleef, Hagae-Comitum, pp.

Doto awapa was found on a colony of the hydroid, Aglaophenia sp. (family Aglaopheniidae) on which it presumably feeds. Many other species of Doto also feed on hydroids of the family Aglaopheniidae and the other families in the superfamily Plumularioidea.

This species was first described from Brittany, France. It has rarely been reported since the original description. Henning Lemche identified it with the common species which feeds on the hydroid Dynamena pumila, predominantly in the intertidal region.Just, H, & Edmunds, M. 1985.

This hydroid grows as a sparsely branched colony to 3 cm in height.Ramil, F.(J.), J. Parapar & W. Vervoort, 1992. The genus Sertularella Gray, 1848 (Cnidaria: Hydrozoa) along the coasts of Galicia (Spain). Zool. Meded., Leiden 66 37: 493-524.

Aequorea victoria juvenile medusae are asexually budded off hydroid colonies in late spring; these free-living hydromedusae will spend all of their lives in the plankton. The medusa spends its first stage of life growing quickly, and after reaching approximately 3 cm will begin producing gametes for reproduction. Each medusa is either a male or a female. The eggs and spermatozoa mature daily in the medusa gonads, given enough food, and are free-spawned into the water column in response to a daily light cue, where they are fertilized and eventually settle out to form a new hydroid colony.

Obelia longissima is a colonial species of hydrozoan in the order Leptomedusae. Its hydroid form grows as feathery stems resembling seaweed from a basal stolon. It is found in many temperate and cold seas world-wide but is absent from the tropics.

Hydroids of B. aberrans feed on fragments of other cnidarians. Cnidaria have a centered mouth surrounded by tentacles. Also, the they are carnivorous. In terms of reproduction, gametes were released before or shortly after the release of the mediating from the hydroid.

Pagurus dalli, commonly known as the whiteknee hermit, is a species of hermit crab in the family Paguridae. It is found in the northeastern Pacific Ocean at depths down to about . It usually lives in a mutualistic symbiosis with a sponge, or sometimes a hydroid.

Doto acuta is found on colonies of the hydroid, Obelia geniculata (family Campanulariidae), on which it feeds. The eggs normally hatch into young slugs after metamorphosis (direct development), or there may be a short swimming larval phase of 2 days.Opisthobranchia des Mittelmeeres. Nudibranchia und Saccoglossa.

Hydroids in this family can be solitary or colonial. When colonial, the hydranths or hydroid polyps are either linked by stolons or are branched. The hydranths have one or more whorls of fine tentacles. The gonophores are free-living medusae or are fixed sporosacs.

The hydroid colonies grow on a variety of hard substrates; they are more robust in shallow water and more lanky in deeper habitats. In the Mediterranean Sea, the colonies are present all year long with the exception of June, the breeding period being from July to February.

The hydroid and early medusa stage of Olindias formosus (Cnidaria, Hydrozoa, Limnomedusae). Journal of the Marine Biological Association of the United Kingdom 94(7): 1409–1415. (close relatives live elsewhere, like O. sambaquiensis found off Argentina and Brazil).Resgalla Junior, C.; A.L. Rosseto; V. Haddad Jr (2011).

Pandeidae is a family of hydroids in the class Hydrozoa. Like other jellyfish there is usually a mature medusa form which is pelagic and reproduces sexually and a hydroid or polyp form which is often benthic and reproduces asexually by budding.Hydromedusae C. E. Mills. Retrieved 2011-10-10.

This hydroid is native to the northeastern Pacific Ocean, its range extending from Vancouver Island to Monterey Bay, California. It occurs in the low intertidal zone and the shallow subtidal zone. It grows on and under rocks and boulders, and on the mollusc shells occupied by hermit crabs.

The color of digestive gland duct is bright red but the apical cnidosac is white in color. The jaw plates are purplish red and they show through each side of the slug's head as a reddish color spot. It was reported that it feeds on the hydroid, Eudendrium.

Doto ussi is found on colonies of the stinging hydroid, Aglaophenia cupressina (family Aglaopheniidae), on which it presumably feeds.Doto ussi, photo by Hung Chi- Feng on Flickr Many other species of Doto also feed on hydroids of the family Aglaopheniidae and the other families in the superfamily Plumularioidea.

The tubular hydroid resembles a long-stemmed narrow-petalled flower. The stem is encased in a sheath. The polyps are pink or orange and white, with an outer ring of long tentacles. There are short tentacles surrounding the mouth rising from a cluster of yellow bead-like bunches of reproductive sporosacs.

This species was described from Hayama, Sagami Bay, Japan. Additional specimens included in the original description were from Tannowa, Osaka Bay; from among a hydroid colony on Ecklonia leaves at Mukaishima, Seto Inland Sea and from Abugashima, Toyama Bay. It has been photographed at Kurosaki, Toyama Bay.Anon. (2015) Eubranchus horii.

Hydroid colonies arise or stand upright due to creeping hydrorhiza. Monosiphonic or polysiphonic hydrocaulus are companions of erect colonies. Bougainvillia aberrans is distinguishable in the sense that the degree of reduction of its medusa is unique compared to species of same genus. Moreover, B. aberrans is suppressed in the medusa stage.

The grey fan hydroid grows as a grey to dark brown fan-shaped colony that may be 40 cm in total height. It has variable branching in a single plane. The main stem of old colonies can be quite thick and flattened in the plane of branching. Smaller branches are round in section.

He retired to Clifton and studied zoophytes, especially in Devon. He published A history of the British hydroid zoophytes (1868) and A history of the British marine Polyzoa (1880). In June 1872, he was elected a Fellow of the Royal Society. At least six genera and 13 species of invertebrates are named in his honour.

When these produce buds, they become detached and grow on as new individuals c. Section through a hydroid The majority of hydroids are colonial. The original polyp is anchored to a solid substrate and forms a bud which remains attached to its parent. This in turn buds and in this way a stem is formed.

Since 2012, the LCFC is part of the project BioCapTech and contribute to the design of new water treatment systems. The joint venture with the Agence nationale de la recherche aims to design a new humanoid robot, nicknamed Hydroid. The laboratory is also implied in the projet Corousso, focused on the friction stir welding process.

Budding only happened when the hydroids were kept at water temperatures of ; not or . In contrast, the two warmer temperatures appeared to produce more medusae. This indicates that hydroid growth and reproduction (budding) occur in or less, while warmer temperatures initiate the change into medusae. This matches the annual sea temperature variations observed in its native range.

Myja hyotan is a slender nudibranch with unusual elongate cerata which mimic the polyps of its hydroid prey, Pennaria. It is similar to Myja longicornis but differs in the shape of the cerata, which in this species have a long stalk, then a large swelling, a constriction and another swelling tapering to the tip. It grows to in length.

243–256 Kirchenpauer continued with these studies after returning to Hamburg in 1864:Nachruf in: Leopoldina. Amtliches Organ der Kaiserlichen Leopoldino-Carolinischen Deutschen Akademie der Naturforscher, Year of publoication: 23 (1887), p. 58. between 1862 and 1884 he would publish six papers on hydroids, describing eight new nominal genera and seventy-seven new nominal hydroid species.

The hydroid B. muscus is widely distributed around the British Isles. It favours sheltered waters and is tolerant of low salinity levels. The medusae have been recorded around the coasts of Britain, the North Sea, Norway, south-west Ireland, the Isles of Scilly, the Bay of Biscay, the Mediterranean Sea and near Rhode Island in the United States.

The sessile colonial stage of Obelia longissima is the most long-lived and the most easily observed of its life stages. The hydroid looks superficially like fronds of seaweed. It has a basal stolon growing in close proximity with the substrate. Out of this grow fragile, flexible stems up to high each with short side branches.

Haleciidae is a family of hydrozoans. Their hydroid colonies emerge from a creeping hydrorhiza and usually form upright branching colonies, although some species' colonies are stolonal. Their gonophores are typically sporosacs, growing singly or bunched into a glomulus. They remain attached to the hydroids or break off to be passively drifted away; in a few, the gonophores are naked.

These dried hydroid colonies are commonly sold as a curiosity, as a decorative "indoor plant", or as underwater decorations for aquaria in stores. They are sometimes labeled as "Neptune plants". Despite a superficial resemblance to plants, they are actually animal skeletons or shells. The dried colonies are often dyed green, but, when soaked in water, the coloring will dissolve.

The marine worms identified at the Houtman Abrolhos include 22 species of the polychaete family Terebellidae, and 16 species of the family oligochaete family Tubificidae. For a list of species, see list of worms of the Houtman Abrolhos. A total of 38 hydroid species have been collected at the Houtman Abrolhos. 34 of these are leptothecates, the remainder being anthoathecates.

Eudendrium racemosum is a marine species of cnidaria, a hydroid (Hydrozoa) in the family Eudendriidae. It was described by Cavolini in 1785.World Register of Marine Species Retrieved November 9, 2012 Hydroids are one of the most abundant organisms in hard-substratum benthic communities, more specifically in temperate seas, such as the Mediterranean. Similar to most modular organisms, they have high growth rates.

This is a colonial hydroid with a branching, tree-like form growing to a height of about . The main branches divide into rather longer but narrower branches which bear single cup-shaped, feeding polyps known as hydranths near their tips. Each hydranth has about twenty tentacles but no nematophores. These hydranths are connected with the rest of the colony by hollow tubelike hydrocauli.

This aeolid feeds on hydroids. In common with other aeolid nudibranchs, the cerata of black-dot nudibranch aid in respiration but also contain extensions of the digestive system. The nudibranch eats the hydroid and passes its nematocysts unharmed through its digestive system to the tips of its cerata. Here the nematocysts mature and are then used by the nudibranch for its own defence.

B. muscus is a colonial hydroid forming irregular, straggling branched bushes. The individual polyps have two rings of tentacles pointing alternately upwards and downwards. The colony may grow to about 120 millimetres in height with polyps up to three millimetres long.Encyclopedia of Marine Life of Britain and Ireland The hydranths are cylindrical or fusiform and are bright red or pink.

This hydroid branches rather sparsely and irregularly compared with Sertularella gayi. The main stems and side branches are thin, wavy, and of a pale straw colour. As in all Sertularella species, the side branches support alternate hydrothecae, one to each internode. The hydrothecae are bulbous at the base and become narrower towards the rim which has four cusps, and an operculum that consists of four triangular flaps.

The form of the hydroid is very variable and this was one of the reasons for the taxonomical confusion. In the "muscus" form, single polyps or short branches emerge from a stolon. In the "fruticosa" form, the hydrocaulis is much branched and grows to fifty millimetres in height. The perisarc rises to the base of the tentacles which may form a corrugated or membranous cup.

P. canaliculata also preys on a common freshwater gymnolaemate, but with less devastating effect. Indigenous snails do not feed on bryozoans. Several species of the hydroid family Zancleidae have symbiotic relationships with bryozoans, some of which are beneficial to the hydroids while others are parasitic. Modifications appear in the shapes of some these hydroids, for example smaller tentacles or encrustation of the roots by bryozoans.

Arrow crab) on Aglaophenia cupressina (Stinging hydroid). Small decorator crabs, like this one, are often found wearing snipped-off tips of stinging hydroids on their heads to fend off predators. Hydroids are a life stage for most animals of the class Hydrozoa, small predators related to jellyfish. Some hydroids such as the freshwater Hydra are solitary, with the polyp attached directly to the substrate.

Having settled, the larvae undergo metamorphosis into the hydroid stage of the lifecycle, forming tiny sessile polyps called scyphistomae. Under favorable conditions these bud and form further scyphistomae. In due course, when they have acquired zooxanthellae and the temperature exceeds , these strobilate (split) and new medusae are formed. In Florida, the medusae are found all the year round but the scyphistomae are only present in late summer and fall.

The tubular sponge hydroid grows to about tall. It has a fat stem and a daisy-like polyp with sparse tentacles surrounding a group of reproductive sporosacs which in turn surround the pink and white oral tentacles. The body of the hydranths (feeding individuals) as well as the gonophores (reproductive polyps) are pinky red, while the tentacles are transparent white.Branch, G.M.; Branch, M.L.; Griffiths, C.L.; Beckley, L.E. 2010.

A hydroid is a type of vascular cell that occurs in certain bryophytes. In some mosses such as members of the Polytrichaceae family, hydroids form the innermost layer of cells in the stem. At maturity they are long, colourless, thin walled cells of small diameter, containing water but no living protoplasm. Collectively, hydroids function as a conducting tissue, known as the hydrome, transporting water and minerals drawn from the soil.

This aeolid feeds on hydroids of the genus Eudendrium. In common with other aeolid nudibranchs, the cerata of the purple lady aid in respiration but also contain extensions of the digestive system. The purple lady eats the hydroid and passes its nematocysts unharmed through its digestive system to the tips of its cerata. Here the nematocysts mature and are then used by the nudibranch for its own defence.

The candy nudibranch eats hydroids of the genus Sertularella. In common with other aeolid nudibranchs, the cerata of the candy nudibranch aid in respiration but also contain extensions of the digestive system. The candy nudibranch eats the hydroid and passes its nematocysts unharmed through its digestive system to the tips of its cerata. Here the nematocysts mature and are then used by the nudibranch for its own defence.

This aeolid feeds on hydroids of the genus Eudendrium. In common with other aeolid nudibranchs, the cerata of white-edged nudibranch aid in respiration but also contain extensions of the digestive system. The white-edged nudibranch eats the hydroid and passes its nematocysts unharmed through its digestive system to the tips of its cerata. Here the nematocysts mature and are then used by the nudibranch for its own defence.

The hydroid Halecium muricatum, Norway. The shallow, usually even-rimmed hydrothecae are sessile or borne on a hydrophore; their bottom is formed by a concentric diaphragm, with a row of small knobs distally to it. They are so small in height as to lack an operculum, but are maintained and repaired throughout the individual animal's life. The hydranths much exceed the hydrothecae in size and are quite sturdy.

Obelia dichotoma is widely distributed throughout protected marine and freshwaters and, like many other hydroids, colonies attach to structures such as pilings, debris, seaweeds, grasses, and barnacles at depths from <25m up to 275m. O. dichotoma is relatively uncommon in the open coast such as beach areas. This hydroid has been found on both coasts of the U.S., Mediterranean Sea, around Australia, and the southern tip of Africa.

The medusa (jellyfish) is free-living in the plankton. Dense nerve net cells are also present in the epidermis in the cap. They form a large ring-like structure above the radial canal commonly presented in cnidarians. Turritopsis dohrnii also has a bottom-living polyp form, or hydroid, which consists of stolons that run along the substrate and upright branches with feeding polyps that can produce medusa buds.

The tidal river, between Cotehele Quay and Weir Quay, with its mudbanks and reed beds. The Plymouth Sound and Estuaries are a European Special Area of Conservation. Rocky reefs in low salinity estuarine conditions far inland on the Tamar are very unusual and support species such as the hydroid Cordylophora caspia. The Tamar is one of a few estuaries where zonation of rocky habitats (intertidal and subtidal) can be observed along an estuarine gradient.

The hydroid colony, which can range from bright blue turquoise to yellow, resembles tentacles like those of the jellyfish"Identification Chart for Jellies." Archived 2009-02-21 at the Wayback Machine. Each strand has numerous branchlets, each of the knobs of stinging cells called nematocysts terminates at the distal end. The blue button has a single mouth located beneath the float, which is used for both the intake of prey and the expulsion of wastes.

Myja karin is a slender nudibranch with unusual elongate cerata which mimic the polyps of its hydroid prey, Pennaria. It is similar to Myja longicornis but differs in having far more cerata, ten pairs in a long individual whilst Myja longicornis had only 7 pairs in animals of long. Although found together at the same site, this species and Myja hyotan differ in shape of the cerata, details of colouration, anatomy and molecular distances.

Structure of hydramacin-1 A hydra (size: several millimetres) Hydramacin-1 is a type of antimicrobial protein. It was first isolated and reproduced in 2008 from cells of the freshwater hydroid Hydra. Only around 60 amino acids long, the protein is unique both in amino acid sequence and tertiary structure, prompting its classification in a new family of proteins, the macins. The protein's unusual structure is most likely a reason for the compound's potent antimicrobial qualities.

In a research study, 10 different species of demosponge were found growing on a single Antarctic scallop. The demosponge Homaxinella balfourensis was one of the commonest epibionts growing harmlessly on the scallop's shell. The relationship between sponge and scallop may be symbiotic; the sponge avoids being engulfed in sediment while the scallop benefits from the protection provided by the sponge, which is distasteful to many predators. The hydroid Hydractinia angusta has a mutualistic relationship with the scallop.

In 1888, Axel Elof Jäderholm entered the Uppsala University where he earned his undergraduate degree in 1892, and his doctorate in 1898. His doctoral research was about the South American Peperomia. Between 1903 and 1905, he worked on hydroid collections at the Swedish Museum of Natural History in Stockholm and the Imperial St Petersburg Academy of Sciences. Axel Elof Jäderholm established two new genera and 69 new species of hydroids, most of which are still valid today.

The fertilized egg produces a planular larva which, in most species, quickly attaches itself to the sea bottom. The larva develops into the hydroid stage of the lifecycle, a tiny sessile polyp called a scyphistoma. The scyphistoma reproduces asexually, producing similar polyps by budding, and then either transforming into a medusa, or budding several medusae off from its upper surface via a process called strobilation. The medusae are initially microscopic and may take years to reach sexual maturity.

The medusae of hydrozoans are smaller than those of typical jellyfish, ranging from in diameter. Although most hydrozoans have a medusoid stage, this is not always free-living, and in many species, exists solely as a sexually reproducing bud on the surface of the hydroid colony. Sometimes, these medusoid buds may be so degenerated as to entirely lack tentacles or mouths, essentially consisting of an isolated gonad. The body consists of a dome-like umbrella ringed by tentacles.

Schuchert (2005) Some enigmatic actively swimming medusae have been tentatively placed in this family as a kind of "wastebin taxon". Should their associated hydroids turn out to belong elsewhere, they are to be moved to that family and genus. The relationships of this fairly small but distinctive radiation to other families of Leptothecata are not well understood at present. However, the family Lovenellidae, often turn out to contain the hydroid stage of medusae formerly placed in the family Haleciidae.

A thecate hydroid with a hydrotheca long enough to enclose the hydranth, feeding polyp, when fully contracted. The bell or goblet shaped hydrotheca lacks an operculum, but contains a diaphragm at the base and changes to a brown color over time. The rim of the hydrotheca is smooth or softly toothed and can be used to distinguish O. dichotoma from other Obelia species. O. dichotoma polyp heigh ranges from 215-300 μm and diameter from 210-275 μm.

These polyps develop over a few days into tiny 1 mm medusae, which are liberated and swim free from the parent hydroid colony. Images of both the medusa and polyp of the closely related species Turritopsis rubra from New Zealand can be found online. Until a recent genetic study, it was thought that Turritopsis rubra and Turritopsis nutricula were the same. It is not known whether or not T. rubra medusae can also transform back into polyps.

Like many Hydrozoa, Velella velella has a bipartite life cycle, with a form of alternation of generations. The deep blue, by-the-wind sailors that are recognized by many beach-goers are the polyp phase of the life cycle. Each "individual" with its sail is really a hydroid colony, with many polyps that feed on ocean plankton. These are connected by a canal system that enables the colony to share whatever food is ingested by individual polyps.

Curiously, although a healthy captive Velella will release many medusae under the microscope, and are expected to do the same in the sea, the medusae of Velella are rarely captured in the plankton and very little is known about their natural history. The medusae develop to sexual maturity within about three weeks in the laboratory and their free-spawned eggs and sperm develop into a planktonic larva called a conaria, which develops into a new floating Velella hydroid colony.

This hydroid consists of a single polyp on a tapering stalk which arises from sand or gravel. The colouration is translucent white or pale pink and the stem has pale lines that run longitudinally from the base to where it joins the polyp. The polyp size is relatively large and bends over towards one side, this feature is responsible for the hydroid's name (nutans is Latin for nodding). Typically there are 30 to 40 long, thin tentacles surrounding approximately 80 shorter, finer ones.

In the outer bay zone beds of kelp thrive with foliose brown algaes and several varieties of the axinellid sponge species have colonised the reefs. Other communities tolerant of vertical or steeply sloped bedrock are thriving also. A rare crab Pirimela denticulata and hydroid Tamarisca tamarisca both live in the bay. In the sublittoral zones of the bay lives the burrowing urchin Echinocardium cordatum whose hairy shells regularly turn up on the shores, seagrass Zostera marina and oysters Ostrea edulis.

Since publication the genus has been treated only once, in R. H. Zander's 1993 Genera of the Pottiaceae: Mosses of Harsh Environments. Zander found its morphology to be transitional between the Pottiaceae and the Calymperaceae, having many properties characteristic of the latter, and many properties characteristic of both. The only character of Calymperastrum that does not occur in the Calastraceae is the presence of a leaf hydroid strand. In 1999 the genus was accepted as valid in Crosby's A Checklist of Mosses.

The bean clam may reach one inch in length, and is of varying coloration, often cream, buff, orange or blue and frequently featuring darker rays projecting from the hinge area. The shells are relatively thick, and wedge-shaped, with a polished periostracum. The muscular foot is used by the clam to dig rapidly back into the sand when the clam is exposed by the waves. The bean clam hydroid, Phialidium bakeri, is often found attached to the posterior end of the shell.

Huxley's paper "On the anatomy and the affinities of the family of Medusae" was published in 1849 by the Royal Society in its Philosophical Transactions. Huxley united the Hydroid and Sertularian polyps with the Medusae to form a class to which he subsequently gave the name of Hydrozoa. The connection he made was that all the members of the class consisted of two cell layers, enclosing a central cavity or stomach. This is characteristic of the phylum now called the Cnidaria.

The floats are not obvious in this species from Haeckel's description, and have not been formally described, although the strange hat- like structure on the hydrozoan's aboral side may have this function. The hydroid colony itself closely resembles the tentacles of a scyphozoan; however, each tentacle structure is an individual zooid, which may consist of a medusa or a polyp. Each strand consists of numerous branchlets, which all end in stinging nematocysts. The species is considered to be neustonic, passively drifting on the surface of the sea.

Like other hermit crabs, P. dalli uses an empty gastropod mollusc shell to protect its soft parts, primarily its abdomen. It usually lives symbiotically with a sponge such as Suberites ficus or Suberites latus, which overgrows and eventually dissolves the shell. The sponge benefits from the crab's ability to move away from predators such as nudibranchs, while the crab may benefit from the sponge's unpalatability and the camouflage it provides. P. dalli has been found enveloped in a similar way by the colonial hydroid Schuchertinia milleri.

This species is often found in association with the sea anemone Protanthea simplex in very sheltered deep water, usually on littoral bedrock, silty boulders and rock slopes in fiords and other areas with calm waters. They are often accompanied by the parchment worm Chaetopterus variopedatus, encrusting red algae and the polychaete worm Pomatoceros triqueter. Other members of the community may be the saddle oyster Pododesmus patelliformis and the fan worm Sabella pavonina. Scattered colonies of Alcyonium digitatum are occasionally present along with the hydroid Bougainvillia muscus.

A proboscis allows them to suck nutrients from soft-bodied invertebrates, and their digestive tract has diverticula extending into the legs. hydroid Certain pycnogonids are so small that each of their very tiny muscles consists of only one single cell, surrounded by connective tissue. The anterior region consists of the proboscis, which has fairly limited dorsoventral and lateral movement, and three to four appendages including the s, which are used in caring for young and cleaning as well as courtship. In some species, the chelifores, palps and ovigers can be reduced or missing in adults.

Several of the site’s 24 islets provide undisturbed sandy beach habitat for nesting green turtles, as well as forest and shrubland supporting breeding populations of terns and other seabirds. Its coral reefs support a distinct community of marine benthic plants and animals, a diverse decapod crustacean and hydroid fauna, and feeding habitat for migratory shorebirds and seabirds. Seaweed communities are also important. There are no known native terrestrial mammals within the Reserves; introduced black rats were present on South West Coringa Islet for many years, but were eliminated by 1991 after an eradication program.

REMUS 100 used by Finnish Navy Woods Hole Oceanographic Institution (WHOI) REMUS 100 with autonomous docking station (2007) The REMUS (Remote Environmental Monitoring UnitS) series are autonomous underwater vehicles (AUVs) made by the Woods Hole Oceanographic Institution and designed by their Oceanographic Systems Lab (OSL). More recently REMUS vehicles have been manufactured by the spinoff company Hydroid Inc. a wholly owned subsidiary of Kongsberg Maritime. The series are designed to be low cost, they have shared control software and electronic subsystems and can be operated from a laptop computer.

Self- decorated sea urchin Self-decoration is employed by animals in different groups, including decorator crabs, which attach materials from their environment, as well as living organisms, to camouflage themselves. For example, the Japanese hermit crab, Eupagurus constans, has the hydroid Hydractinia sodalis growing all over the shell that it lives in. Another hermit crab, Eupagurus cuanensis, has the aposematic orange sponge Suberites domuncula which is bitter-tasting and not eaten by fish. Similarly, sea urchins use their tube feet to pick up debris from the bottom and attach it to their upper surfaces.

Colonies of this hydroid consist of a carpet-like mat of stolons, interspersed with long spines, from which arise singly three different types of polyp; feeding polyps known as gastrozooids, reproductive polyps known as gonozooids and finger-shaped polyps known as dactylozooids. The stolons have a chitinous covering known as perisarc but the polyps are naked. The gastrozooids are pink, up to tall with a ring of 12 to 20 tentacles surrounding the mouth. The colony is either male or female, so all the gonozoids are the same sex.

This hydroid grows to a maximum height of but a more typical height is . The colony grows in a single plane with stiff erect stems growing from a fibrous base. The growth is pinnate, with alternate secondary branches which are parallel to one another and join the main stem at an angle of about 50°, giving a herring-bone appearance. These in turn have stubby tertiary branches which bear the hydrothecae (feeding polyps); these grow on alternate sides of the stem, forming short, equal-length segments, separated by transverse nodes.

This hydroid is known from the eastern Atlantic Ocean, the western Atlantic Ocean and the eastern Pacific Ocean. Its range extends from Spitsbergen, through the Mediterranean Sea and the coasts of Western Europe and West Africa to South Africa. It is also present in western Iceland and eastern Greenland, and southwards along the eastern coasts of North America to the Caribbean Sea and Colombia. In the eastern Pacific Ocean its range extends from Alaska to California and it is also present in the Mollucas, Japan and the Sea of Okhotsk.

Solanderia ericopsis is a hydroid in the family Solanderiidae, the group commonly known as tree hydroids or sea fan hydroids. S. ericopsis forms very large, conspicuous colonies from 5 to 50 cm in height, which are often noted by divers. They are usually strictly fan-shaped but can sometimes be bushy. The colonies can be unusually long-lived: during long-term monitoring of defined rock areas around the Poor Knights Islands, one researcher observed a single colony of S. ericopsis over fifteen years, during which it reached 50 cm in height.

The Pearl and Hermes Atoll provides an extensive and unique habitat for invertebrates, including various sponges and thirty- three species of stony corals. Some invasive invertebrate species have been found on the reef, including the orange-striped sea anemone, which is native to Japan, and the Christmas tree hydroid, which competes with native invertebrates for space. The atoll was once heavily populated with black-lip pearl oysters, but overfishing from 1927–1930 caused the population to crash to only 470 in 1930. An expedition in 1950 turned up only six live oysters, and another in 1969 only found one.

The blue button can grow up to 30 mm in diameter and lives on the surface of the sea and consists of two main parts: the float and the hydroid colony. The hard golden brown float is round, almost flat, and about one inch wide. The float organ is responsible for the organism’s vertical movementFryer G, Stanley GD (2004) A Silurian porpitoid hydrozoan from Cumbria, England, and a note on porpitoid relationships. Palaeontology 47(5):1109–1119 and also contains pores that are able to communicate with other P. porpita organisms as well as its surroundings.

Commercially available AUVs include various designs, such as the small REMUS 100 AUV originally developed by Woods Hole Oceanographic Institution in the US and now produced commercially by Hydroid, Inc. (a wholly owned subsidiary of Kongsberg Maritime); the larger HUGIN 1000 and 3000 AUVs developed by Kongsberg Maritime and Norwegian Defence Research Establishment; the Bluefin Robotics vehicles and the International Submarine Engineering Ltd. Most AUVs follow the traditional torpedo shape as this is seen as the best compromise between size, usable volume, hydrodynamic efficiency and ease of handling. There are some vehicles that make use of a modular design, enabling components to be changed easily by the operators.

Hydroid colonies are usually dioecious, which means they have separate sexes—all the polyps in each colony are either male or female, but not usually both sexes in the same colony. In some species, the reproductive polyps, known as gonozooids (or "gonotheca" in thecate hydrozoans) bud off asexually produced medusae. These tiny, new medusae (which are either male or female) mature and spawn, releasing gametes freely into the sea in most cases. Zygotes become free-swimming planula larvae or actinula larvae that either settle on a suitable substrate (in the case of planulae), or swim and develop into another medusa or polyp directly (actinulae).