Genus Actinostola Verrill, 1883

Museums

Regional Maps

• Actinostola Verrill, A.E. 1883. Report on the Anthozoa, and on some additional species dredged by the Blake in 1877-1879, and by the U.S. Fish Commission steamer Fish Hawk in 1880-82. Bulletin of the Museum of Comparative Zoology, Harvard 11: 1-72 [56].

  Type species:

   Urticina callosa Verrill, 1882 by original designation.

Distribution

States

Tasmania

IBRA and IMCRA regions

IMCRA

Macquarie Island Province (24), Tasmanian Shelf Province (36)

Diagnosis

Actinostolidae with the body sometimes short, sometimes cup-like, sometimes long, cylindrical. Column usually thick, firm, slightly rugose or almost smooth, or with flat tubercles produced by mesogloeal thickenings. Sphincter comparatively weak, mesogloeal, so that the upper part of the column cannot perfectly cover the tentacles. Tentacles short, the inner considerably longer than the outer, never more numerous than the mesenteries at the base; sometimes with mesogloeal thickening on their aboral sides at the base; outside provided at their tips with microbasic b-mastigophores. Longitudinal muscles of tentacles and radial muscles of oral disc mesogloeal. Two well developed siphonoglyphs. Numerous perfect mesenteries, hexamerously arranged. The two mesenteries in one and the same pair, from the third or the fourth cycle, irregularly arranged but as a rule orientated so that the mesentery which turns its longitudinal muscle towards the nearest mesentery of the preceding cycle is more developed than its partner. Retractors of mesenteries diffuse, parietobasilar and basilar muscles strong. Mesenteries of the two first cycles sterile. Cnidom: spirocysts, basitrichs, microbasic p- and b-mastigophores.

History of changes