Genus Ophiologimus H.L. Clark, 1911

Type species

Ophiologimus hexactis H.L. Clark, 1911, by original designation.

Diagnosis

LAPs with large, conspicuous tentacle notches; spine articulations not on elevated ridge and not sunken into depressions or notches; ventral portion of lateral arm plate strongly protruding ventroproximalwards; generally no spurs on outer proximal and inner distal edges of LAP.

Remarks

The LAPs of extant species of Ophiologimus are characterised by very large, generally deeply incised tentacle notches, the absence of a strong constriction or a strongly elevated distal portion, the moderately large, freestanding spine articulations and the relatively simple ridge on the inner side devoid of strongly widened parts. Closest similarities are shared with the LAPs of extinct Lapidaster gen. nov., which differ mainly in the possession of at least one spur on the outer proximal and inner distal edges. As discussed above, it seems highly probable that Ophiologimus and Lapidaster gen. nov. come from a single lineage, in view of the striking similarities in LAP morphology displayed by both genera.