Triphora hemileuca Tomlin, 1931

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

Triphora hemileuca Tomlin, 1931

Figure 101

Triphora hemileuca Tomlin 1931: 426, pl. 33, fig. 4.

Type locality.

Port Shepstone, Natal, South Africa.

Type material.

Holotype: NHMUK 1931.7.23.6, fixed by monotypy .

Original description.

Shell with a protoconch of 3 whorls, which are irregularly crossed by axial riblets; protoconch and next three whorls cream-white, last six whorls brown-black; there are twelve whorls in all, of which nos. 4 to 7 have a prominent central keel, cut into tubercles by numerous axial riblets, and fine spiral lines above and below the keel. The last five whorls have three tuberculiferous keels, one immediately below the suture, and two on the lower half of the whorl very close together and only separated by a fine groove, the interspaces being filled with fine spirals as before. Periphery sharply keeled; base of shell and canal much lighter brown.

Alt. 6 mm.; diam. max. 1.5 mm.

Hab.-Port Shepstone (Burnup).

This specimen is unique, but is so extraordinarily perfect in every way that I do not hesitate to describe it. There is the usual raised line round the suture, and a considerable interval between the uppermost keel and the two lower ones on each whorl. The coloration will at once be recognizable.

Diagnosis.

Holotype height 5.4 mm. Shell cyrtoconoid, with eight weakly rounded teleoconch whorls with three spiral cords. The second develops on the fourth whorl. Tubercles are present at the intersection with orthocline axial ribs. Two or three fine spiral threads are visible in the interspace between the main spiral cords. Peristome with a moderately deep posterior sinus and no additional spiral cords. Siphonal canal short. Base with two additional weakly tubercled spiral cords. Protoconch paucispiral with 2.5 whorls with wavy thick axial ribs and interspaces smaller than the ribs. Colour deep brown. The proconch and the first two teleoconch whorls are pure white.

Remarks.

No other type specimens were reported for the NMW ( Trew 1990).

Figures

Figure 101. Triphora hemileuca Tomlin, 1931, South Africa. A Original figure. B-G, I-K Holotype, NHMUK 1931.7.23.6: front (B, C), side (D, E), back (F), protoconch (G, I), peristome (J), aperture (K). H Original label. Scale bars: B-F: 1 mm; G, I: 0.2 mm; J, K: 0.5 mm.