Triforis gracilior E.A. Smith, 1903

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

Triforis gracilior E.A. Smith, 1903

Figure 88

Triforis gracilior E.A. Smith 1903: 614, pl. 35, figs 18, 19.

Type locality.

S. Nilandu Atoll, 1-36 fathoms, Maldives.

Type material.

Syntypes: NHMUK 1903.9.17.16: 1 specimen, Maldive Islands .

Original description.

Testa T. excellenti similis, sed gracilior, cingulis duobus inferioribus subundulatis, alba, hic illic fusco maculata.

Longit. 28 mm., diam. 5½.

Like T. excellens, this species has three keels upon each whorl, but they are not so equal, the uppermost being a trifle more slender than the others. The latter also are slightly affected by faint longitudinal depressions giving them an obscurely beaded appearance. The body-whorl is bicarinate at the periphery and has three or four lirae beneath. As in the preceding species, the space between the second and third keel is a little broader than that which separates the first and second, and the suture is filo-lirate.

Translation of the Latin text.

Shell similar to T. excellens , but more slender, the two lower cords are slightly undulated, white with irregular brown spots.

Height 28 mm, diameter 5½.

Diagnosis.

Syntype 29.4 mm high. Shell conical, very elongated; apical part missing. The remaining teleoconch has 23 whorls bearing two main thin weakly tubercled spiral cords; two more thin ones are visible sub- and suprasuturally. Base with three additional faint spiral cords. Peristome with a shallow posterior sinus. Siphonal canal slightly elongated. Protoconch missing. Teleoconch white with narrow orange vertical flecks.

Remarks.

The general appearance and sculpture is very similar to T. smithi G.B. Sowerby III, 1904, although the latter lacks the orange flecks observable in T. gracilior . E.A. Smith (1916) suggested that T. smithi is a synonym of T. gracilior .

Figures

Figure 88. Triforis gracilior E. A. Smith, 1903, South Nilandu Atoll, Maldives. A-F Syntype NHMUK 1903.9.17.16: front (A), side (B), back (C), original labels (D, E), peristome (F). G Original figures. Scale bars: A-C: 4 mm; F: 2 mm