Trifora convexa E.A. Smith, 1904

Albano, Paolo G., Bakker, Piet A. J. & Sabelli, Bruno, 2019, Annotated catalogue of the types of Triphoridae (Mollusca, Gastropoda) in the Natural History Museum of the United Kingdom, London, Zoosystematics and Evolution 95 (1), pp. 161-308 : 161

Trifora convexa E.A. Smith, 1904

Figure 85

Trifora convexa E.A. Smith 1904: 37, pl. 3, fig. 9.

Type locality.

"Port Alfred, Cape Colony" (Cape of Good Hope, South Africa).

Type material.

Syntypes: NHMUK 1903.12.19.1084-1086: 3 specimens (glued on cardboard), Port Alfred, South Africa .

Original description.

Testa parva, fusca, ad apicem albida; anfractus 10 convexi, supremi duo pallidi, laeves, caeteri tricingulati, cingulis granosis, duobus inferioribus magis conspicuis, sutura filiformi sejuncti, ultimus ad peripheriam rotundatus, cingulis sex instructus; labrum subpatulum; columella callo crasso pellucido induta, supra incurva.

Longit. 5.5 millim., diam. fere 2.

The suture is marked by the lira which encircles the periphery of the body-whorl, and winds up the spire at, but above the actual suture.

Translation of the Latin text.

Small shell, brown, with whitish apex; 10 convex whorls, the uppermost two pale, light, the other with three granulated cords, the lower two more conspicuous, separated by a threadlike suture, the last rounded at its periphery, with six cords; extended lip; columella covered by a large translucent callus, curved above.

Height 5.5 mm, diameter about 2 mm.

Diagnosis.

Syntype NHMUK 1903.12.19.1084 (Fig. 85A-F ) 5 mm high. Shell conical with seven rounded whorls bearing three solid spiral cords with weak nodules at the intersection with orthocline axial ribs. A fourth thin smooth cord can be seen suprasuturally. Peristome incomplete, apparently without additional spiral cords. Base with three large flat spiral cords similar in appearance to those on the whorls. Siphonal canal short. Protoconch paucispiral. The transition between protoconch and teleoconch is very difficult to recognize because the apex is worn, but the protoconch is apparently less than two whorls, the first being smooth and the second with a fine suprasutural smooth spiral cord. Teleoconch brown to orange; protoconch lighter, almost white.

Figures

Figure 85. Trifora convexa E. A. Smith, 1904, Port Alfred, South Africa. A-F, H-J Syntype NHMUK 1903.12.19.1084: front (A, B), side (C, D), back (E), original label (F), peristome (H), protoconch (I, J). G Original figure. Scale bars: A-E: 1 mm; H: 0.5 mm; I, J: 0.2 mm.