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Armorhydridae
Armorhydridae is a family of cnidarians belonging to the order Limnomedusae Limnomedusae is an order of hydrozoans. Taxonomy The taxon was erected by Danish marine biologist Paul Lassenius Kramp in 1938 to accommodate certain families of hydrozoans with biphasic life histories. It includes genera with medusae with e .... Genera: * '' Armorhydra'' Swedmark & Teissier, 1958 References Limnomedusae Cnidarian families {{Hydrozoa-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Limnomedusae
Limnomedusae is an order of hydrozoans. Taxonomy The taxon was erected by Danish marine biologist Paul Lassenius Kramp in 1938 to accommodate certain families of hydrozoans with biphasic life histories. It includes genera with medusae with ecto-endodermal statocysts and with gonads alongside their radial canals, and also genera which have polyps that are not covered by a theca. Molecular analysis performed by Collins in 2006 has since shown that the Limnomedusae are not monophylic. The family Armorhydridae, which contains a single genus and a single species, '' Armorhydra janowiczi'', is found living in coarse sediment, has hollow tentacles and has no radial canals. It seems to share few morphological features with the other families and probably belongs elsewhere. The inclusion of Microhydrulidae is also dubious. The medusa stage is not known and the tiny polyp has no tentacles nor mouth. Systematic list The World Register of Marine Species currently lists the following ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cnidarians
Cnidaria () is a phylum under kingdom Animalia containing over 11,000 species of aquatic animals found both in freshwater and marine environments, predominantly the latter. Their distinguishing feature is cnidocytes, specialized cells that they use mainly for capturing prey. Their bodies consist of mesoglea, a non-living jelly-like substance, sandwiched between two layers of epithelium that are mostly one cell thick. Cnidarians mostly have two basic body forms: swimming medusae and sessile polyps, both of which are radially symmetrical with mouths surrounded by tentacles that bear cnidocytes. Both forms have a single orifice and body cavity that are used for digestion and respiration. Many cnidarian species produce colonies that are single organisms composed of medusa-like or polyp-like zooids, or both (hence they are trimorphic). Cnidarians' activities are coordinated by a decentralized nerve net and simple receptors. Several free-swimming species of Cubozoa and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
