Genus Comitas Finlay, 1926

(family Pseudomelatomidae)

Comitas Finlay, 1926: 251 .

Type species

Surcula oamarutica Suter, 1917

(= Drillia fusiformis Hutton, 1877) (Lower Miocene, New Zealand) (OD).

Remarks

Species of Comitas have a very distinctive radula (Fig. 3F), reliably distinguishing them from all other conoideans, including Leucosyrinx . Nonetheless, the radula was examined in very few species, namely: Comitas galatheae Powell, 1969 (Kosuge 1986: pl. 33 figs 7–11); C. murrawolga (Garrard, 1961) and C. onokeana vivens Dell, 1956 (Kantor & Taylor 2000: fig. 2a–e); C. pachycercus Sysoev & Bouchet, 2001 (Sysoev & Bouchet 2001: figs 14, 16); Comitas sp. (Bouchet et al. 2011: fig. 15c–d). The mentioned species together with the type species of the genus can be separated from Leucosyrinx on the following conchological characters: the shell is generally large, usually over 50 mm in length, with broad and long axial ribs, always extending to the periphery and sometimes to the shell base. The anal sinus is moderately deep, medium broad U-shaped, on the subsutural ramp and occupying the lower part of the subsutural ramp, not on all its width, so that the deepest point is closer to shoulder than to suture (Fig. 3E). Correspondingly the sinus line in its upper part is prosocline, but convex.

There is significant overlap in shell characters between Comitas and Leucosyrinx, so that attributing the species known only from empty shells is sometimes problematic. Thus, although Powell (1966) recognized the differences in position of the anal sinus between these genera, he attributed without discussion numerous species with subsutural sinus to Comitas (Powell 1969) that are conchologically closer to Leucosyrinx as defined here.