Tiefsee‐Aktinien der Familie Actinoscyphiidae aus dem IMordatlantik (Actiniaria, Mesomyaria)

• Published in: Zoologica Scripta
• Main Author: RIEMANN‐ZÜRNECK, KARIN
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 1978
• Subjects: Stephenson; Venus; North Atlantic
• Online Access: http://dx.doi.org/10.1111/j.1463-6409.1978.tb00597.x; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fj.1463-6409.1978.tb00597.x; https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1463-6409.1978.tb00597.x

Actinoscyphia saginata (Verrill, 1882; type species) and Actinoscyphia aurelia (Stephenson, 1918) are redescribed with special reference to characters of diagnostic significance in order to differentiate the two species both inhabiting the 2000 m slope region of the North Atlantic. In situ photograph of A. aurelia off the North West African coast shows it to display a novel life form type in expanding its bi‐lobed tentacular disc like a Venus‐fly‐trap and standing on the muddy sediment with a small, non‐adhesive base penetrating just below the surface of the sediment. The peculiar nematocyst equipment found in both species makes it necessary to rehabilitate the family Actinoscyphiidae Stephenson, 1920. The systematic position of the family is discussed and eventually the Actinoscyphiidae is considered as sister group (sensu Hennig) of the Hormathiidae. Because of the loss of acontia in the Actinoscyphiidae, this taxon is considered to be the more advanced one. Chondrodactis japonica Wassilieff, 1908, is found to belong to the genus Actinoscyphia.