Cerithium pusillum Pfeiffer L., 1840

Albano, Paolo G. & Bakker, Piet A. J., 2016, Annotated catalogue of the types of Triphoridae (Mollusca, Gastropoda) in the Museum fuer Naturkunde, Berlin, with lectotype designations, Zoosystematics and Evolution 92 (1), pp. 33-78 : 34

Taxon classification Animalia Caenogastropoda Cerithiidae

Cerithium pusillum Pfeiffer L., 1840 Figure 1

Cerithium pusillum L. Pfeiffer, 1840: 256, not illustrated.

Type specimens.

Lectotype: ZMB/Moll no. 117874a, here designated. Paralectotype A: ZMB/Moll no. 117874b; further 49 paralectotypes (ZMB/Moll no. 117874).

Type locality.

Cuba.

Original description.

Testa sinistrorsa turrita tenui cinnamomea; anfract. 11 planis, sulcis longitudinalibus et transversis granuloso-decussatis; sutura profunda; canali brevissimo, vix recurvo; labro simplice, expanso. Long. 2½, diam. ¾ lin.

Translation.

A light brown sinistral shell composed of 11 flat whorls with tubercled spiral ribs. Deep suture. Siphonal canal very short, barely bent. Lip simple, expanded. Length 2.5 linien ( “lines”), diameter 0.75 linie (L. Pfeiffer probably used the "Preussische Mass" widely used after 1816 until introduction of the metric system; a linie is equivalent to 2.179 mm).

Diagnosis.

Lectotype height 5.2 mm, but shells up to 6 mm are present in the type material. Pupoid shape, with deep sutures. Teleconch of 7-9 whorls. Three granulated spiral cords present: the second appears later, in the second half of the spire. A smooth suprasutural cord also present. The last whorl has a fourth weakly tubercled spiral cord, and the base has further two smooth spiral cords. Peristome simple, without bifurcating cords. Multispiral apex of 4-5 whorls, the lower three with two spiral keels and axial riblets. Colour brown; lip white with brown bands.

Remarks.

Rolán and Fernández-Garcés (2008) considered this taxon a nomen dubium. Indeed, L. Pfeiffer’s type specimens were thought to be in the Cuming collection (NHMUK) or in the Dhorn collection in the Stettin Museum, which was totally destroyed during the II World War ( Dance 1966). Rolán visited the NHMUK without reporting any material on this species ( Rolán and Fernández-Garcés 2008). Pfeiffer did not illustrate the species, and the original description is very brief.

In the ZMB/Moll there are two lots of this species from the Dunker collection. The first lot is labelled Cerithium pusillum (Fig. 1, E) and composed of 51 mostly worn specimens from Cuba, and obtained from Pfeiffer ( “Pfr.” on label). This material is consistent with the original description. These specimens are therefore considered to belong to the type series. To stabilize nomenclature, the best preserved specimen is here designated as the lectotype (Fig. 1, A-D, ZMB/Moll no. 117874a). Among the 50 paralectotypes, another well preserved specimen was segregated as 'paralectotype A’ and here illustrated (Fig. 1, G-M, ZMB/Moll no. 117874b). The second lot contains 13 far better preserved specimens labelled as coming from “Westindien” (= Western Indies) and also from the Dunker collection. They are clearly conspecific with Cerithium pusillum , and provide a useful addition for a better illustration of fine diagnostic characters (e.g. apex sculpture) but are not considered to be types.