Juxtamusium sp. A

Dijkstra, Henk H. & Maestrati, Philippe, 2013, New species and new records of bathyal living Pectinoidea (Bivalvia: Propeamussiidae: Pectinidae) from the Southwest Pacific, Zoosystema 35 (4), pp. 469-478 : 477

Juxtamusium sp. A

( Fig. 3 A-D)

MATERIAL EXAMINED. — Vanuatu. BOA 1, stn 16°42’S, 167°53’E, 91-103 m, 1 spm.

REMARKS. — The present specimen is morphologically closest to Juxtamusium maldivense (Smith, 1903) , known from the western and northwestern Indian Ocean anwd western and southwestern Pacific, but differs by several characters: in having a weakly undulated shell disc ( J. maldivense is always flat), in having more delicate irregularly spaced radial riblets ( J. maldivense with fewer, more prominent radial riblets), in lacking the pseudoctenolium on the left valve (present in J. maldivense ), and in having carinate sculpture on the inner side (undulated in J. maldivense ).

In shape the present specimen looks like a species of Anguipecten Dall, Bartsch & Rehder, 1938 , somewhat like a juvenile of Anguipecten lamberti (Souverbie in Souverbie & Montrouzier, 1874), but could be clearly differentiated by the oblique internal ligament (typical for Juxtamusium ). This species will be described, when more material becomes available for comparison.

Figures

FIG. 3. — Juxtamusium sp.: A-D, pair valve; A, external view of the left valve; B, external view of the right valve; C, internal view of the left valve; D, internal view of the right valve. Scale bar: 1 cm.