Mastonia maenades 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 : 81

Mastonia maenades Jousseaume, 1898 ( Fig. 53 )

Mastonia maenades Jousseaume, 1898: 72 , not illustrated.

ORIGINAL LOCALITIES. — Aden, Perim Island (Bab al-Mandab Strait, Yemen), Djibouti.

TYPE MATERIAL. — Syntypes. Djibouti • MNHN-IM-2000-485 ; 6 specimens . Saudi Arabia • MNHN-IM-2000-510; 3 specimens; Jeddah .

ORIGINAL DESCRIPTION. — Testa solida, elongato-turrita, apice acuminata, nitens, alba, maculis ferrugineis longitrorsum irregulariter picta, granulis biseriatim dispositis cincta, intervallum funiculo parum granulosa divisum; anfr. 15-16 sutura sat distincta separati, primi 4 fulvi, sequentes 2 albi, alteri ferrugineo-maculati, ultimus contractus, costis quinis granulosis rugatus, ad basim laevus, apertura subovalis lateraliter fissa; canalis brevis parum abrupte recurvatus.Long. 5 mm 5; diam. 1 mm 5. [Latin diagnosis followed by a discussion in French]

TRANSLATION OF THE LATIN TEXT. — Solid shell, turreted-elongated, acute apex, bright, white, with irregular rust-coloured spots, with two series of granules, interspaces are separated by a slightly granular little cord; from 15 to 16 whorls separated by a quite distinct suture, first four whorls are brown, subsequent are white, the other whorls present rust-coloured spots, last whorl restricted, with five granular spiral cords, left-handed at the base, subovate and laterally fissured aperture; short siphon, abruptly and slightly curved. Length 5 mm; diameter 1.5 mm.

DIAGNOSIS. — Shell conical with flat sides. Illustrated syntype 6.1 mm high. Teleoconch of 11 whorls. Three spiral cords present, the second appearing on the sixth 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. Spiral microsculpture of weakly granulate fine threads. Peristome with short additional spiral cords below the second and third spiral cord. Base with two additional spiral cords of which the first developing tubercles and the second smooth. Protoconch incomplete in the syntype, but clearly multispiral with two spiral keels and axial riblets.Teleoconch with the first two whorls white, others with brown blotches on a whitish background. Protoconch brown.

Figures

FIG. 53. — Mastonia maenades Jousseaume, 1898, Djibouti: A-J, syntype, MNHN-IM-2000-485 front (A, B), side (C, D), back (E), protoconch (F, G), microsculpture (H), peristome (I, J); K, original label. Scale bars: A-E, 1 mm; F, G, 0.1 mm; H, 0.2 mm; I, J, 0.4 mm.