Eudendriidae
Eudendriidae | ||||||||||||
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![]() Flabellina affinis (Gmelin, 1791) (Gastropoda, Aeolidoidea) on their diet Eudendrium racemosus |
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Systematics | ||||||||||||
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Scientific name | ||||||||||||
Eudendriidae | ||||||||||||
Agassiz , 1862 |
The Eudendriidae are an exclusive marine, worldwide occurring family of the Hydrozoa (Hydrozoa). The family currently includes around 85 species.
features
The hydroid polyps form colonies that are connected by stolons, sometimes also upright sticks with a branched trunk that extend from a hydrorhiza . The single polyps usually have a stalk. The trunk, twigs and stems, sometimes even the lower parts of the hydrant , are covered by perisarc . The hydrants are relatively large, urn-shaped with an offset, trumpet-shaped mouth cone (hypostome). Directly below the cone of the mouth sit one or more wreaths of filiform, solid tentacles. The polyp body sometimes has a basal, tentacle-like extension. Near the base, the polyp has a ring with nettle cells just above the peridermal pit. Sexual reproduction takes place via spore sacs that sit on the hydrant directly above the tentacles. The gender polyp is often reduced to a blastostyle, ie it no longer has a mouth. The male gonophores are usually arranged linearly in several chambers. The female gonophores originally have a curved piston (spadix), each piston contains a single egg. The desmonemes are absent in the cnidome and only eurytele nettle cells are present.
Geographical occurrence
The representatives of the family are spread around the world. While the genus Myrionema is limited to warmer seas, comes Eudendrium before including sub-Antarctic and polar seas in cooler regions.
Systematics
The family currently consists of only two genera:
- Eudendrium Ehrenberg, 1834
- Myrionema Pictet, 1893
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. In: Zootaxa 1668, 2007, ISSN 1175-5326 , pp. 127-182, abstract (PDF; 406 kB) .
- AC Marques, H. Mergner, R. Höinghaus, CMD Santos and Willem Vervoort: Morphological study and taxonomical notes on Eudendriidae (Cnidaria: Hydrozoa: Athecatae / Anthomedusae). Zool. Med. Leiden, 74 (5): 75-118, Leiden 2000 ISSN 0024-0672 .
On-line
Web links
- Image of Eudendrium racemosum grown up on a sea squirt colony