Mastonia iniqua Jousseaume, 1898

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 : 72-73

Mastonia iniqua Jousseaume, 1898

( Fig. 48 )

Mastonia iniqua Jousseaume, 1898: 75 , not illustrated.

TYPE LOCALITY. — New Caledonia.

TYPE MATERIAL. — Lectotype. New Caledonia • MNHN-IM-2000-1175, designated by Marshall (1983).

Paralectotype. New Caledonia • MNHN-IM-2000-1264; 1 specimen .

ORIGINAL DESCRIPTION. — Testa solidula, elongata , turrita, alba spiraliter nigro cincta; antice parum tumida; anfr. 13-14 regulariter crescenti, primi albi laevigati, sequentes tuberculis nitentibus triseries dispositis ornati, series postica forstior nigro tincta, alterae 2 albae, ultimus costis moniliformibus quinque rugatus, quorum anticae 2 nigrae intertio-albo divisae, medianae 2 albae, postica nigra; apertura subovalis lineis nigris 2-3 zonata, lateraliter fissa, canalis brevis apice nigro maculatus. Long. 4mm 5; diam. 1mm 2.

[Latin diagnosis followed by a discussion in French]

TRANSLATION OF THE LATIN TEXT. — Slightly solid shell, elongated, turreted, with white and brown spiral cords; anteriorly slightly swollen; from 13 to 14 regularly growing whorls, first whorls are smooth and white, subsequent whorls are adorned by three series of bright tubercles, the posterior series is coloured in brown, the other two in white, the last whorl is characterised by five tubercled spiral cords of which the two anterior brown cords are separated by two median white cords, the posterior cord is brown; subovate aperture banded with 2-3 brown lines, laterally fissured, short siphon spotted in brown. Length 4.5 mm; diameter 1.2 mm.

DIAGNOSIS. — Shell cyrtoconoid. Lectotype 4.5 mm high, paralectotype 2.9 mm high. Teleoconch of 7-9 whorls. Three spiral cords present, the second appearing on the fifth whorl. First and third cords with tubercles at the intersection with rather orthocline axial ribs. Second cord initially with thin tubercles later becoming larger. Spiral microsculpture of barely visible fine threads. Peristome without additional spiral cords. Posterior sinus shallow. Base with three additional spiral cords, the first and second with tubercles, the third smooth. Multispiral protoconch of 4.5 whorls with one spiral keel and equally strong axial riblets. Teleoconch white with the first spiral cord and the two spiral cords on the base brown. Tip of the siphonal canal brown. Protoconch white.

Figures

FIG. 48. — Mastonia iniqua Jousseaume, 1898, New Caledonia: A-H, lectotype, MNHN-IM-2000-1175; front (A, B), side (C, D), back (E), peristome (F, G), microsculpture (H); I-M, paralectotype, MNHN-IM-2000-1264; front (I), side (J), back (K), apex (L, M); N, O, original labels lot MNHN-IM-2000-1175. Scale bars: A-E, I-K, 1 mm; F-H, L, M, 0.2 mm.