Genus Hormosoma Stephenson, 1918

Museums

Regional Maps

• Hormosoma Stephenson, T.A. 1918. Coelenterata. Part I. Actiniaria. Natural History Report of the British Antarctic Terra Nova Expedition 5(1): 1-68 [29-33].

  Type species:

   Hormosoma scotti Stephenson, 1918 by original designation.

Distribution

Other Regions

Australian Antarctic Territory

Diagnosis

Actinostolidae with well developed pedal disc. Column smooth, thick, with a submarginal collar. Sphincter strong, mesogloeal. Tentacles short, but thick, arranged in several cycles, the inner longer than the outer. Outermost cycle of tentacles on their aboral sides at the base provided with a more or less distinct battery of microbasic b-mastigophores. Longitudinal muscles of tentacles and radial muscles of oral disc mesogloeal. Oral disc wide. 2 very broad siphonoglyphs, aborally prolonged. Tentacles and mesenteries hexamerously arranged. 2 pairs of directives. About same number of tentacles and mesenteries. Perfect pairs of mesenteries fairly numerous. Retractors with coarse folds forming a small pennon close to the gonads. Parietobasilar muscles very broad, forming a deep fold, basilar muscles strong. All mesenteries, sometimes except the directives, fertile. Cnidom: spirocysts, basitrichs, microbasic b- and p-mastigophores.

History of changes