Aeginidae | |
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Bathykorus bouilloni | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Cnidaria |
Class: | Hydrozoa |
Order: | Narcomedusae |
Family: | Aeginidae Gegenbauer, 1857 [1] |
Genera | |
See text | |
Synonyms | |
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Aeginidae is a family of hydrozoans in the order Narcomedusae. The family comprises 6 genera and 8 species.
The following genera are recognized in the family Aeginidae: [1]
Hydrozoans with dome-shaped bells and tentacles set above the undulating margin of the bell. There are gastric pouches containing the gonads situated between the tentacles, the number of pouches being greater than the number of tentacles. The pouches extend below the points of origin of the primary tentacles. Some genera have a peripheral canal system and others do not, and some have secondary tentacles. [2]
Hydrozoa is a taxonomic class of individually very small, predatory animals, some solitary and some colonial, most of which inhabit saline water. The colonies of the colonial species can be large, and in some cases the specialized individual animals cannot survive outside the colony. A few genera within this class live in freshwater habitats. Hydrozoans are related to jellyfish and corals and belong to the phylum Cnidaria.
Semaeostomeae is an order of large jellyfish characterized by four long, frilly oral arms flanking their quadrate mouths. The umbrella is domed with scalloped margins, and the gastrovascular system consists of four unbranched pouches radiating outwards from the central stomach; no ring canal is present. They usually possess eight tentacles; four are per-radical and four are inter-radical.
Solmissus, or dinner plate jellyfish, is a genus of hydrozoans. Its species are unique among cnidarians in that they actively hunt for prey as opposed to passively waiting for plankton to pass by. They are found in the deep waters of Monterey Bay, California. They are most likely to be found in the deep sea, mid water. They grow to be 20 cm (7.9 in) in diameter. These hydrozoans feed on gelatinous zooplankton, including salps and doliolids, ctenophores, jellyfish, and copepods. However, Solmissus may be limited to feeding on soft-bodied prey by the type of nematocysts on their tentacles (Mills).
Leptothecata, or thecate hydroids, are an order of hydrozoans in the phylum Cnidaria. Their closest living relatives are the athecate hydroids, which are similar enough to have always been considered closely related, and the very apomorphic Siphonophorae, which were placed outside the "Hydroida". Given that there are no firm rules for synonymy for high-ranked taxa, alternative names like Leptomedusa, Thecaphora or Thecata, with or without the ending emended to "-ae", are also often used for Leptothecata.
Rhopalonematidae is a family of hydrozoans. The family comprises 15 genera and 36 species.
Cladonematidae is a small family of anthomedusan hydrozoans. They have stolonal hydroid colonies, and their medusae are benthic and can crawl across the sediment; in many species they have lost the ability to swim however.
Lovenellidae is a family of hydrozoans. Their hydroids live together in upright stolonal or sympodial colonies, and their gonophores are pedunculate free-roaming medusae. The relationships of this fairly small but distinctive radiation to other members of the order Leptothecata are not well understood at present.
Narcomedusae is an order of hydrozoans in the subclass Trachylinae. Members of this order do not normally have a polyp stage. The medusa has a dome-shaped bell with thin sides. The tentacles are attached above the lobed margin of the bell with usually a gastric pouch above each. There are no bulbs on the tentacles and no radial canals. Narcomedusans are mostly inhabitants of the open sea and deep waters. They can be found in the Mediterranean in large numbers.
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.
Cuninidae is a family of hydrozoans in the order Narcomedusae. They have dome-shaped bells and tentacles set above the undulating margin of the bell. Their gastric pouches contain the gonads situated in line with the tentacles, the number of pouches being the same as the number of tentacles. The pouches do not extend below the points of origin of the primary tentacles. Members of some genera have a peripheral canal system and others do not. No radial canals or secondary tentacles are present.
Solmarisidae is a family of hydrozoans in the order Narcomedusae. The name is sometimes spelled "Solmaridae".
Tetraplatia is a genus of hydrozoans in the order Narcomedusae. It is the sole genus in the monotypic family Tetraplatidae.
Bathykorus bouilloni is a species of hydrozoan first described in 2010. It is a deep-sea species found in the Arctic Ocean, and appears to be common at depths below 1,000 m (3,300 ft). It is the only species in the monotypic genus Bathykorus. The genus name comes from the Greek bathy meaning "deep" and korus meaning "helmet", referring to the depth at which this species is found and to the shape of the bell. Its helmet-like appearance bears a resemblance to the helmet of Darth Vader, giving it the nickname Darth Vader jellyfish. The specific name is in honour of Dr. Jean Bouillon, (1926–2009), a marine zoologist.
Limnomedusae is an order of hydrozoans.
Olindiidae is a family of hydrozoans in the order Limnomedusae. They have a polyp phase and a medusa phase. The polyps are generally small (1 mm) and solitary, but a few species are colonial. They have a varying number of tentacles and can reproduce by budding. In the largest species, the medusae can grow to 15 cm (6 in). Centripetal canals may be present or absent and the radial canals are unbranched. The gonads are beside the radial canals, except in Limnocnida, where they are on the manubrium. The fertilised eggs develop into planula larvae which become polyps. These multiply asexually or can bud off medusae. In some species, medusae are only produced when the water temperature exceeds a certain level. Most species are marine, but several can also be found in brackish water and a few, notably Craspedacusta and Limnocnida, are found in fresh water.
Corynidae is a family of hydrozoans in the order Anthomedusae.
Filifera is a suborder of hydrozoans in the order Anthoathecata. They are found in marine, brackish and freshwater habitats.
Aeginura is a genus of hydrozoans in the family Aeginidae.
Aegina rosea is a species of hydrozoan of the family Aeginidae. It is one of two species in the genus Aegina, which was believed to be monotypic, until molecular phylogenetic analysis revealed that Aegina rosea was a second species.
Zancleidae is a family of cnidarians belonging to the order Anthoathecata.