Cerion latisinus Pilsbry & Black, 1930

Original Description

"Cerion latisinus  new species.  Plate 22, fig. 9 a-d.

The shell is shortly rimate, cylindric, the upper fourth tapering to the obtuse apex. Color, Vandyke brown with white ribs and maculation (or white, copiously striped with Vandyke brown) , the first two whorls yellowish. Sculpture of regular, closely set ribs, mainly a little narrower than their intervals, 29 on the penult whorl; on the base the ribs are finer and more numerous. The whorls are slightly convex, the last ascending slowly in front. The aperture is dark within, a moderately developed parietal tooth and a very small, deeply placed columellar, remote from the parietal. The peristome is white, rather narrowly reflected, its face strongly thickened; parietal margin strongly developed.

Length 20 mm.,   diam.   above   aperture   8   mm.;   10 1/2   whorls.   Type.

    "     25.3  "          "           "             "       8     "  ;   11 1/2     "

    "      16    "          "           "             "     6.3    "  ;    9 2/3      "

"While the species rather closely resembles some New Providence forms of the varium group, we do not find that any similar finely ribbed species has been recorded from Andros. However, the larger C. pepperi from N.E. Andros may prove to intergrade with latisinus when the intermediate territory is explored.

            In the series collected there is great variation in size as the figures and measurements show. Fig. 9c represents an immature specimen which has not completed the peristome.

            Specimens were also taken at Purser Point among drifted shells.

            We are inclined to believe that a series of larger shells found in drift at Purser Point with typical C. latisinus and C. rhyssum may belong to the latisinus series, but as forms from various widely separated colonies are likely to he brought together in such drift, their status will be uncertain until living colonies are investigated. These shells run from 20 x 8.7 mm. to 37 x 15 mm. in size. The larger ones have considerable esemblance to certain forms of C. rhyssum."  (Pilsbry & Black, 1930:292-293)
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