Conical shell, number of whorls 7, shell light brown in colour, elongate and conical, whorl rounded, convex and gradually increasing in size downward, aperture small and ovate, operculum paucispiral
, shell sculptured with reddish markings, vertical weakly curved ribs and much finer spiral striations.
Although the paucispiral
form (ca 1.25 whorls) is typical of vetigastropods and the apical beak consistently absent or only weakly developed, features associated with the terminal lip and superficial sculpture vary significantly.
Shell dextral with ovate, horny and paucispiral
operculum dark brown in color.
It is not known if the young emerge as veliger larvae or crawling juveniles, but the large, simple, paucispiral
protoconch (larval shell) is indicative of non-plank-totrophic development (11), (12).
The operculum in Nesopoma and Setaepoma is unusual in being multispiral, whereas in most rissooideans, including all other assimineids, truncatellids and pomatiopsids it is paucispiral
. In A.
In the genus Pseudodaphnella this is generally paucispiral
and papilliform with more or less orthocline axial riblets and weak spiral threads.