Cytaeididae
| Cytaeididae | ||||||||||||
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Cytaeididae | ||||||||||||
| Agassiz , 1862 |
The Cytaeididae are a family of the Hydrozoa (Hydrozoa). The family currently includes around 20 species.
features
The hydroid polyps are sessile and usually not differentiated into defense and feeding polyps. However, there are occasionally two size classes of polyps, of which the smaller ones then act as defense polyps. The hydrorhiza is reticulated and covered by the perisarc . The hydrant are bare, only at the base the perisarc forms a cup-shaped collar. The filiform tentacles sit in a wreath directly below the cone of the mouth (hypostome). The gonophores sit directly on the hydrorhiza and develop into free- living medusae , medusoids or spore sacs. The umbrella of the medusa is bell-shaped with four or eight solid marginal tentacles. The mouth is ring-shaped and simple with four unbranched oral mouth tentacles. They have four radial channels and one ring channel. The gonads are attached interradially or surround the manubrium . There are no ocelli .
Geographical occurrence
The types of the family are distributed almost worldwide. The distribution area extends from the tropics to polar and Antarctic waters.
Systematics
Peter Schuchert lists three genera under this family in the "Hydrozoa Directory":
- Cytaeis Eschscholtz, 1829
- Paracytaeis bouillon, 1978
- Perarella Stechow, 1922
swell
literature
- Marymegan Daly, Mercer R. Brugler, Paulyn Cartwright, Allen G. Collin, Michael N. Dawson, Daphne G. Fautin, Scott C. France, Catherine S. McFadden, Dennis M. Opresko, Estefania Rodriguez, Sandra L. Romano & Joel L. Stake: The phylum Cnidaria: A review of phylogenetic patterns and diversity 300 years after Linnaeus. Zootaxa, 1668: 127-182, Wellington 2007 ISSN 1175-5326 Abstract - PDF
- Jean Bouillon and Fernando Boero: Synopsis of the families and genera of the hydromedusae of the world, with a list of worldwide species. Thalassia Salentina, 24, 47-296, Galatina 2000 ISSN 0563-3745 PDF .