Pillsburiaster Halpern 1970

Pillsburiaster Halpern, 1970c Halpern 1970c: 2; McKnight 1973: 180; Downey in Clark & Downey 1992: 258; McKnight 2001: 102 (key); Mah 2011: 1,4 (in key), 39. Diagnosis Body pentagonal in most species, weakly stellate in some (R/r=1.4 to 2.0). Abactinal plates mound-like to flat, weakly tabulate, arranged irregularly. Abactinal surface densely covered by numerous, coarse, spherical granules forming close clusters, obscuring plate boundaries in some species. Secondary plates present. Marginal plates numerous, 14 to 35 per interradius. Bald region, variably small to large present centrally on superomarginal plate surface, absent in one species. Furrow spines 2 to 10. Subambulacral spines 2 to 4, thick, widely spaced followed by small but coarse granules in irregular arrangement. Pedicellariae, when present, spatulate. Comments Pillsburiaster includes seven species, which occur primarily in deep-sea (120–2008 m) settings. Three species, P. aoteanus McKnight 1973, P. indutilus McKnight 2006, and P. maini McKnight 1973 are known only from New Zealand. Two species, P. geographicus Halpern 1970 and P. calvus Mah 2011 were described from the tropical Atlantic and Burdwood Bank in the South Atlantic, respectively. Finally, Pillsburiaster annandaiei Koehler 1910 and P. ernesti Ludwig, 1905 were collected from the Indian Ocean and the Cocos Islands, in the East Pacific, respectively. Mah (2011) briefly reviewed high-latitutde species of Pillsburiaster. Nothing is known regarding biology or ecology of Pillsburiaster spp. The new species described below represents a new farthest extent record for Pillsburiaster in the Northern Hemisphere.