Triphora cana Verco, 1909

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 cana Verco, 1909

Figure 107

Triphora cana Verco 1909: 289, pl. XXIII, figs 2-4.

Type locality.

"Gulf St. Vincent" (South Australia).

Type material.

Lectotype: SAM D. 13439 (fide Marshall 1983; not seen, see Remarks). Paralectotypes: NHMUK 1910.3.29.43-44: 2 specimens, Gulf St. Vincent, South Australia .

Original description.

Shell sinistral, solid, of 12 whorls, elongate-conical. Protoconch slightly mamillate, of two whorls; the second the larger, convex, with sigmoid axial bars, 16 in a whorl. Spirewhorls, the first with one nodulous carina, the second with two, the third with three, the last arising between the other two. Whorls sloping, the last three subconvex. Sutural space distinct, with a supra-sutural thread in the last six spaces, remaining nearly smooth. Tubercles close, about 18 in the penultimate, joined transversely and axially (obliquely forwards) by stout bars which lattice the surface. Aperture roundly rhomboidal, scarcely pinched behind. Outer lip slightly retrocurrent towards the suture; basal lip in contact with the erect, solid inner lip, and crossing the columella, where it closes in the short recurved notched, otherwise open canal. Base flatly convex, bounded by the nearly smooth peripheral lira, with a second smooth basal lira and a third encircling the base of the canal. The protoconch and first four spire-whorls are white, the rest light-brown.

Dim.- Length, 71 mm.; breadth, 2.1 mm.

Locality. - Type, Gulf St. Vincent, depth unrecorded, with 15 good and 34 moderate examples; 35 fathoms, St. Francis Island, 1 good; 40 fathoms off Beachport, 1 good and 1 poor; 55 fathoms off Cape Borda, 3 good and 5 poor; 62 fathoms off Cape Borda, 1 moderate and 3 poor; 110 fathoms off Beachport, 2 moderate; St. Francis Island beach, 5 good, 1 poor.

The species varies a great deal -

1. In colour. The first six whorls may be white, and all the rest a blackish-brown. The first three whorls (including the protoconch) may be dark-brown, and all the rest light-brown, with no white whorls. The three apical whorls may be brown, the next three white, and the rest brown, so connecting the previous shell with the type. The three apical whorls may be brown, and the seven remaining whorls quite white. The infra-sutural pearl row in the coloured portion may be dark-purple or barely tinted, the others brown, or the highest and lowest row may be purple and the central brown.

2. In shape. In most examples, though not in the type, the posterior pearl row becomes larger than the others, the pearls being greater, and consequently closer, and are somewhat axially elongate. When this is marked the whorl may be wider below the suture than above it, so as to give a more or less gradate appearance to the whorls.

Remarks.

Verco referred to a type series consisting of multiple specimens in the original description. Marshall (1983) reported of the “holotype” in SAM but this specimen should be considered a lectotype according to Article 74.6 of the Code ( ICZN 1999). The label accompanying this lot reports the type locality and the wording “Co-types”, which suggests that the accompanying specimens indeed belong to the type series. Because of Marshall’s lectotype designation, these and all other syntypes are now paralectotypes.

Figures

Figure 107. Triphora cana Verco, 1909, Gulf St. Vincent, South Australia. A-E, H, I, K-M Paralectotype, NHMUK 1910.3.29.43: front (A, B), side (C, D), back (E), protoconch (H, I), peristome (K, L), aperture (M). G Paralectotype, NHMUK 1910.3.29.44: front. F, J, O Original figures. N, P Original labels. Scale bars: A-E, G, M: 1 mm; H, I: 0.2 mm; K, L: 0.5 mm.