Staurodiscus Haeckel, 1879

Schuchert, Peter & Collins, Richard, 2021, Hydromedusae observed during night dives in the Gulf Stream, Revue suisse de Zoologie 128 (2), pp. 237-356 : 284

Genus Staurodiscus Haeckel, 1879

Staurodiscus Haeckel, 1879: 145 ,

type species Staurodiscus tetrastaurus Haeckel, 1879 ( Kramp, 1961: 147) .

Staurodiscalma Haeckel, 1879: 145 , type species Staurodiscus tetrastaurus Haeckel, 1879 by monotypy.

Staurodiscema Haeckel, 1879: 146 , type species Staurodiscus heterosceles Haeckel, 1879 by monotypy.

Toxorchis Haeckel, 1879: 157 , type species Toxorchis arcuatus Haeckel, 1879 by monotypy.

Staurodiscoides Uchida, 1927b: 165 , type species Staurodiscoides gotoi Uchida, 1927 by monotypy.

Diagnosis: Medusa with 4 or more main primary radial canals, some or all branching one or more times, primary canal and some or all of the branches reaching circular canal; gonads on primary radial canals and branches; numerous tentacles and cordyli; with or without cirri; with or without ocelli.

Hydroid epizootic, Hebella -like; hydrothecae almost conical when growing on upper part of the host, cylindrical when growing on lower part of same host; asymmetrical to symmetrical; with everted margin, sharply or slightly oblique, with short to long, wrinkled or annulated pedicels; with membranous diaphragm (sometimes absent) and annular thickening; gonophores as free medusae; gonotheca as big or slightly bigger than hydrotheca, with four opercular flaps, on short pedicel, slightly undulated walls, truncated distally, tapering at base, containing up to three medusae ( Bouillon et al., 2006).

Remarks: See Kramp (1962) and Bouillon (1984b) for emended diagnosis and synopsis of the species. For the life cycle see Migotto & Andrade (2000).