Mastonia cnodax Jousseaume, 1884

Albano, Paolo G., Franco, Davide Di, Azzarone, Michele, J., Piet A., Bakker & Sabelli, Bruno, 2023, Review of the types of Indo-Pacific Triphoridae (Mollusca, Gastropoda) in the Muséum national d’Histoire naturelle, Paris, Zoosystema 45 (2), pp. 13-106 : 66

Mastonia cnodax Jousseaume, 1884

( Fig. 42 )

Mastonia cnodax Jousseaume, 1884: 260 , pl. 4, fig. 14.

TYPE LOCALITY. — New Caledonia.

TYPE MATERIAL. — Syntypes. New Caledonia • MNHN-IM-2000-1613; 6 specimens; from type locality.

ORIGINAL DESCRIPTION. — Testa elongato-turrita, solidula, antice perparum ventricosa, lutescente et tuberculis rufis ornata; anfractibus 15 lente irregulariterque crescentibus (primi albi, laevigati, sequentes tuberculorum seriebus duabus, subdistantibus, suturam obtegentibus, exasperati), sutura fere inconspicua separatis; ultimo tuberculorum rufulorum ordinibus tribus, cincto; apertura subovali lateraliter fissa; canali luteo-albo, brevi, recurvo, superne uni-costato. — Long. 6, lat. 1.5 millim.

[Latin diagnosis followed by a discussion in French]

TRANSLATION OF THE LATIN TEXT. — Turreted-elongated shell, rather solid, anteriorly slightly swollen, yellowish and adorned by red tubercles; whorls are 15, slowly and irregularly growing (first whorls are white, smooth, subsequent ones are characterised by two series of equidistant tubercles and which hide the suture), separated by a generally inconspicuous suture; last whorl with three reddish series of tubercles; subovate and laterally fissured aperture; yellowwhite siphon, short, curved, above with one spiral cord. — Length 6, diameter 1.5 mm.

DIAGNOSIS. — Shell cyrtoconoid. Syntypes 6.3 mm and 6.6 mm high. Teleoconch of 11-12 whorls. Three spiral cords present, the second appearing on the eleventh whorl. First and third cords with tubercles at the intersection with rather prosocline axial ribs. Second cord initially as a fine thread, but later developing thin tubercles. Peristome with additional cords below the second and third spiral cord. Posterior sinus shallow. Base with three additional spiral cords of which the first with thin tubercles and the other two smooth. Protoconch incomplete in the syntypes but clearly multispiral with one strong spiral keel and axial riblets on the lower whorls. Teleoconch with brown tubercles on a whitish background, the brown colour of the tubercles becoming more intense towards the lower whorls. Protoconch light brown.

Figures

FIG. 42. — Mastonia cnodax Jousseaume, 1884, New Caledonia:A, original figure in Jousseaume (1884); B-K, syntype 1, MNHN-IM-2000-1613; front (B, C), side (D, E), back (F), protoconch (G, H), microsculpture (I), peristome (J, K); L-P, syntype 2, MNHN-IM-2000-1613; apex (L), peristome (M), front (N), side (O), back (P); Q-T, original labels. Scale bars: B-F, N-P, 1 mm; G, H, 0.1 mm; I, L, 0.2 mm; J, K, M, 0.4 mm.