Glyptelasma gigas (Annandale, 1916)

Figures 1 A, 3

Poecilasma gigas Annandale, 1916: 299, pl. 4 fig. 4, pl. 5 figs 10–14, pl. 6 figs 7, 8. Megalasma (Glyptelasma) gigas . — Calman, 1919: 364. — Nilsson-Cantell, 1928: 20. — Zevina, 1982: 85, fig. 75. Glyptelasma gigas . — Broch, 1931: 32, fig. 12.

Material examined. NMNS 005087-00078, 8 specimens, Stn. CP132 (22°20.98’N, 120°6.73’E, 21 Nov. 2001, depth: 690–700 m), CL 7.67–15.41 mm, CW 4.46–9.28 mm, PL 3.72–9.79 mm.

Diagnosis. Largest known species of Glyptelasma; peduncle long; carinal base laterally expanded; scutum with basal and occludent margins forming right angle.

Description. Capitulum large, 5 smooth, white, opaque plates, separated by narrow, chitinous inter-spaces (Fig. 1 A); tergum quadrangular, all margins straight; scutum ovoid, occludent margin convex, basal and tergal margins straight, carinal margin strongly convex, basal and occludent margins forming right angle (Fig. 1 A); carina bowed, basal laterally expanded (Fig. 1 A). Peduncle long, yellow, surface concentrically wrinkled (Fig. 1 A). Maxilla bilobed, setae in 2 main clusters (Fig. 3 A); maxillule notched, 2 large, long, cuspidate setae above notch, short spines in notch, 10 cuspidate setae below notch, region below notch expanded outwards (Fig. 3 B); mandible with 6 teeth excluding inferior angle, first tooth separated from remaining teeth, lower margin very short, smooth, inferior angle terminating in 1 sharp seta (Fig. 3 C); mandibular palp narrow, elongated, setae on superior margin (Fig. 3 D); labrum concave, without deep notch, cutting edge with dense, fine teeth (Fig. 3 E, I). Cirrus I with rami subequal; outer ramus 10-segmented, inner ramus 8-segmented (Fig. 3 F); cirrus II with outer ramus 14-segmented, inner ramus 15-segmented (Fig. 3 G); caudal appendage short, 1-segmented, length <height of basal segment of pedicle of cirrus VI (Fig. 3 H).

Distribution. Malaysia, South China Sea, Taiwan.

Remarks. This is a new record for Taiwanese waters.