Calpasoma Fuhrmann, 1939

Calder, Dale R., 2010, Some anthoathecate hydroids and limnopolyps (Cnidaria, Hydrozoa) from the Hawaiian archipelago 2590, Zootaxa 2590 (1), pp. 1-91 : 74-75

Genus Calpasoma Fuhrmann, 1939

Calpasoma Fuhrmann, 1939: 363 .

Type species. Calpasoma dactylopterum Fuhrmann, 1939 , by monotypy.

Diagnosis. Olindiid polyps solitary, although bipolar or tripolar forms sometimes present. Hydranths minute, athecate, sausage-shaped to cylindrical, with distal mouth but without prominent capitulum; tentacles usually present distally, appearing to arise in two close whorls or irregularly arranged, each tentacle a slender and filiform protrusion of an epithelial tentaculocyte; several nematocysts on distal end of each tentacle, scattered elsewhere; asexual reproduction by frustulation or budding.

Gonophores not known.

Remarks. Calpasoma Fuhrmann, 1939 is a peculiar freshwater hydrozoan genus, sometimes believed to be merely a tentaculate form of Craspedacusta Lankester, 1880 . Studies such as those of Matthews (1966), and Rahat & Campbell (1974), support recognition of the two as distinct, although Jankowski (2001) considered at least one form of Calpasoma to be congeneric with Craspedacusta . Astrohydra Hashimoto, 1981 appears similar, but the genus (and its type species, A. japonica Hashimoto, 1981 ) is not well-known.

The generic name Calpasoma is neuter (ICZN Art. 30.1.2), and the specific name of its single contained species should be spelled dactylopterum , not dactyloptera as originally formed.