Actinoscyphia Stephenson, 1920

Gusmão, Luciana C. & Rodríguez, Estefanía, 2021, Deep-Sea Anemones (Cnidaria: Anthozoa: Actiniaria) From The South Atlantic, Bulletin of the American Museum of Natural History 2021 (444), pp. 1-73 : 27

Genus Actinoscyphia Stephenson, 1920

DIAGNOSIS (modified from Carlgren, 1949; modifications in bold): Actinoscyphiidae with pedal disc never flat, sometimes very small, often on worm tubes or sponge spicules. Column thick to very thick, smooth, of gelatinous consistency. Tentacles in two cycles at margin of wide oral disc; tentacles with mesogleal basal aboral thickenings. Oral disc wide, lobed, sometimes bilobed. Longitudinal muscles of tentacles and radial muscles of oral disc ectodermal, sometimes mesoectodermal. Mesogleal sphincter musculature weak. Siphonoglyphs well developed. Mesenteries more numerous than tentacles. Six pairs of perfect and sterile mesenteries with diffuse retractors. All mesenteries thin, delicate, with weak, diffuse retractors. Cnidom: spirocysts, basitrichs, p- mastigophores B1, and holotrichs.

TYPE SPECIES: Actinernus saginata Verrill, 1882 , by original designation.

VALID SPECIES: Actinoscyphia saginata ; A. aurelia ( Stephenson, 1918b) ; A. plebeia (McMurrich, 1893) ; A. groendyki Eash-Loucks and Fautin, 2012 ; (?) A. verrilli ( Gravier, 1918) ( Fautin, 2016) .