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Borgertella caudata (Wallich, 1869)

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Cadium caudatum (p.109):
Body of shell, oval, produced anteriorly into a lengthened neck, which is more or less recurved, so as to place the aperture in a nearly vertical position; posterior extremity, surmounted by a delicate hollow and gradually tapered caudiform process (sometimes twice as long as the body of the shell) forming curve, the direction of which is towards the anterior aperture; surface of shell, sometimes quite plain, sometimes marked as in C. marinum; length of oval body, from 1/250th to 1/350th of an inch.
Wallich 1869
GENUS: Borgertella
Type species: Cadium caudatum Wallich

Diagnosis: Shell constituted of two main parts; an egg-shaped chamber closed at the aboral end and armed with a hollow spine, and a long, more or less curved, trumpet-like peristome. The inner cavities of the two parts are separated by a diaphragm and communicate only through a narrow tube entering the peristomal cavity. If the curvature of the peristome is considered as being ventral, the tube is situated by the right wall of the shell and is directed dorsally. Surface smooth or with longitudinal ridges.

Remarks: Borgertella is proposed for Cadium caudatum Wallich, C. inauris Borgert, and the new species Borgertella erectostoma. It differs from Lirella in having the diaphragm mentioned. Apparently previous authors did not observe this peculiar inner tube which is clearly visible in almost all species observed both in Quaternary and in Upper Miocene sediments.

SPECIES: Borgertella caudata (Wallich)
Cadium caudatum Wallich, Bütschlii, 1882, pl. 32, fig. 15a.
Cadium inauris Borgert, 1910, p. 404, pl. 30, figs. 4-10

Remarks: Most specimens fit the description given by Borgert for C. inauris, except for the arch connecting the oral spine with the aboral one. It is broken in the fossil material, the spines being preserved only by their proximal parts. In the specimens resembling B. caudata no oral spine was observed. As, except for the oral spine, the shells of the two species are quite similar, they appear to be synonymous. Borgert (1910) himself recognized that they are difficult to separate. Borgert’s description should be completed with the description of the diaphragm separating the shell cavity from the peristomal one. The diaphragm is generally perpendicular or slightly oblique to the axis of the shell chamber. The diaphragmic tube is short and directed slightly dorsally.

B. caudata was found in the Quaternary sediments at Sites 203 and 206.
Dumitrica 1973


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