Stylaster Gray, 1831

Cairns, Stephen D. & Lindner, Alberto, 2011, A Revision of the Stylasteridae (Cnidaria, Hydrozoa, Filifera) from Alaska and Adjacent Waters, ZooKeys 158, pp. 1-88 : 27

Genus Stylaster Gray, 1831

Diagnosis.

Colonies branching in a flabellum or a bush shape (in only one case lamellate). Coenosteum usually reticulate-granular but may be linear-imbricate; coenosteum of many colors and hardness. Gastro- and dactylopores arranged in conventional cyclosystem arrangement, with only one gastrostyle per cyclosystem; pores of the peripheral type; supernumerary dactylopores often present. Cyclosystems arranged on branch edges and/or on corallum faces, or uniformly on all branch surfaces, but not unifacially. Gastropore tube single-chambered, but may be constricted by a ring palisade. Dactylostyles present. Ampullae usually superficial.

Discussion.

The genus and its various grouping are discussed by Cairns (1983b) and a key to all stylasterid genera, including the groups of Stylaster , is provided by Cairns (1992). Currently there are 80 recognized Recent species and 7 fossil species ( Appeltans et al. 2011: WoRMS data base: www.marinespecies.org). It is by far the most species-rich and diverse genus of the stylasterids.

Type species.

Madrepora roseus Pallas, 1766, by subsequent designation ( Milne Edwards and Haime 1850: xxii), a member of Group B.

Distribution.

Oligocene to Recent: cosmopolitan from depths of 0-2010 m ( Cairns 1992; Appeltans et al. 2011).