Hacelia Gray, 1840

Gray 1840: 284 [as Ophidiaster (Hacelia) Agassiz, 1836b].

Ludwig 1897: 209; H.L. Clark 1921: 36; Clark & Downey 1992: 271 (as Hacelia).

Comments. Hacelia is a genus of Ophidiasteridae, which includes six species, two in the Atlantic, one from South Africa, and the remaining three in the tropical Pacific, all occurring at moderate depths, 40– 200 m. Hacelia has granule-covered, abactinal plates arranged in regular longitudinal series in ten rows rather than eight and six as in Ophidiaster and Tamaria, respectively. In a manner similar to the differences between Ophidiaster and Tamaria, the boundaries between genera, such as Ophidiaster and Hacelia can be problematic depending on the definitions of how “full longitudinal row” is defined.