Shell solid, strong, yellowish white with darker brown spiral lines and about six whorls. Nucleus smooth brown; sculpture of numerous close-set spiral threads, of which about every third or fourth is stronger and darker colored than the others; transverse sculpture of stout ribs becoming obsolete behind the periphery, thus giving the whorl a shouldered aspect, there are nine or ten of these on the last whorl, extending well forward; the rib behind the aperture is varicoid and swollen; the spiral sculpture passes over the ribs, which are a little angulate at the periphery ; the whorl is appressed to the suture, which in the upper whorls is more or less waved by the ends of the ribs behind it; the aperture is long, narrow, and somewhat contracted, the continuous margin less elevated than in the preceding species; the base of the last whorl is somewhat constricted, the canal is twisted, recurved, and with a strong siphonal fasciole; the outer lip has about seven teeth of which the hinder ones are the stronger; there is a rounded callus on the body and also a few denticulations on the anterior part of the columella. Max. length of shell, 12.0 mm; of last whorl, 9.0 mm; of aperture, 6.0 mm; max. width of shell, 5.8 mm. A larger but imperfect specimen is 15.5 mm. long.
Described by Dall as Nassarina grayi

This is a rather short broad species, and has a little the aspect of a Tritonidea, but the pinched aperture suggests its reference to this group.

Caribic. St Kitts, Barbados. Mexico: off the Arrowsmith Bank, Yucatan.

Vokes (1996) mentioned and illustrated the originally figured syntype of Cantharus laevis as the holotype. Smith (1890) never designated any shell as the holotype. The type material in the NHMUK consists of 5 specimens, mentioned as syntypes by Houart (1997: 56). Vokes (1996) only mentions what she then called the "holotype". but having examined the material when visiting the NHMUK she certain!) was aware of the existence of the other 4 specimens. The mention of Vokes is here considered as an indirect lectotype designation by inference as holotype, following ICZN Art. 74.5: "In a lectotype designation made before 2000, either the term "lectotype", or an exact translation or equivalent expression (e.g. "the type"), must have been used or the author must have unambiguously selected a particular syntype to act as the unique name-bearing type of the taxon. When the original work reveals that the taxon had been based on more than one specimen a subsequent use of the term "holotype" does not constitute a valid lectotype designation unless the author, when wrongly using that term, explicitly indicated that he or she was selecting from the type series that particular specimen to serve as the name-bearing type".
Houart & Abreu illustrated the syntype and only existing specimen of Trophon lowei as the holotype. This is here also considered as a valid lectotype designation following ICZN Art. 74.6: "When it has been accepted that a nominal species-group taxon was based on a single specimen and the original description neither implies nor requires that there were syntypes, and if it is considered subsequently that the original description was based on more than one specimen, the first author to have published before 2000 the assumption that the species-group taxon was based upon a single type specimen is deemed to have designated that specimen as the lectotype".

Discussion. Material consisting of numerous live and dead collected specimens from the southwestern Indian Ocean was examined and initially considered a separate species. Adult specimens are bigger than the typical Atlantic Cytharomorula, wider and more shouldered, have a slightly wider aperture and a narrower siphonal canal. Nevertheless, genetic analysis performed on specimens from Guadeloupe (KARUBENTHOS 2). Walters Shoal (MD 208) and other specimens collected off Mayotte. Comoros and Glorieuses islands confirm the conspecifity of the populations of the Atlantic Ocean and the Indian Ocean. The type material of Trophon lowei (Madeira) and Cantharus laevis (Saint Helena) seems to be composed of intermediate forms between the populations of the western Atlantic and the Canary Islands and those of the Indian Ocean.