Micratys sp. 1

Valdés, Ángel, 2008, Deep-sea “ cephalaspidean ” heterobranchs (Gastropoda) from the tropical southwest Pacific, Mémoires du Muséum national d'Histoire naturelle 196, pp. 587-792 : 772

Micratys sp. 1

Figs 93D, E, 94

MATERIAL EXAMINED. — Norfolk Ridge. BIOCAL: stn DW 70 , 23°25’S, 167°53’E, 965 m, 8 dd .

DISTRIBUTION. — Known only from New Caledonia (Fig. 94), in 965 m.

DESCRIPTION. — Shell morphology. Length 6 mm, width 4 mm (largest specimen examined). Shell solid, oval, with nearly parallel sides (Fig. 93E). Only 1 whorl visible, forming the entire shell. Apex rounded, depressed, slightly umbilicate (Fig. 93D), with the aperture lip rising from the left side. The aperture lip forms a short, rounded wing posteriorly. Anterior end of the shell rounded. Umbilicus present, partially covered by the columella. Aperture long, wide anteriorly, narrowing at about 1/3 of its length. Columellar margin thickened. Sculpture of 5-8 irregular spiral grooves near the posterior end and 8-12 near the anterior end, absent from the middle area of the shell. Colour uniformly whitish.

Anatomy. Unknown. All shells collected lacked soft parts.

REMARKS. — This species is similar in shell morphology to members of the genera Diniatys Iredale, 1936 and Mimatys Habe, 1952 , but differs from them in lacking a columellar tooth or fold. Because of the presence of an apical perforation, a well-developed umbilicus and spiral grooves near the anterior and posterior ends of the shell, it is provisionally included in the genus Micratys .

The shell morphology of this species clearly differs from that of Micratys wareni n. sp. and M. ovum Habe, 1952 in being much more elongate and proportionately narrower. This is probably an undescribed species of Micratys but it is not named here because of the lack of anatomical information.