Echinosphaeraster, Gale, 2021

Gale, Andrew Scott, 2021, Taxonomy and phylogeny of the ‘ football stars’ (Asteroidea, Sphaerasteridae), Journal of Systematic Palaeontology 19 (10), pp. 691-741 : 710

Genus Echinosphaeraster gen. nov.

Type species. Asterias scutatus Goldfuss, 1833 .

Diagnosis. A sphaerasterid in which the large abactinal ossicles of the abactinal surface each carry a tall, conical, centrally placed spine on a raised, crater-shaped circular facet. A small number (approximatey 50) of large abactinal plates, of similar breadth, are present between the ambitus and the primary circlet, set in four rows per radius. The primary circlet is broad and extends across half the diameter of the abactinal surface. The abactinal surface forms a low dome, and the actinal surface is flat.

Derivation of name. Echinos, Greek, meaning spiny.

Included species. Asterias scutatus Goldfuss, 1833 .

Remarks. Echinosphaeraster gen. nov. differs in important features from Sphaeraster , most importantly the smaller number of abactinal plates (about 50) set in four columns per radius that do not taper towards the ambitus and in the presence of very large conical spines placed centrally on the abactinal ossicles above the ambitus.