Euscalpellum rostratum ( Darwin, 1851 )

Chan, Benny K. K., Prabowo, Romanus Edy & Lee, Kwen-Shen, 2010, North West Pacific deep-sea barnacles (Cirripedia, Thoracica) collected by the TAIWAN expeditions, with descriptions of two new species, Zootaxa 2405, pp. 1-47 : 3-5

Euscalpellum rostratum ( Darwin, 1851)

Figures 1 B, 4

Scalpellum rostratum Darwin, 1851: 259 , pl. 6 fig. 7.

Scalpellum (Euscalpellum) rostratum . — Hoek, 1907: 65, pl. 5 fig. 13. — Stubbings, 1936: 19 fig. 7.

Euscalpellum rostratum . — Pilsbry, 1908: 107, figs 1e–f. — Utinomi, 1968: 162, fig. 1. — Zevina, 1978: 1001. — Liu & Ren, 1985: 190, fig. 5, pl. 3 figs 1–2. — Liu & Ren, 2007: 214, fig. 90.

Scalpellum (Smilium) rostratum . — Annandale, 1914: 274.

Smilium rostratum . — Broch, 1931: 14. — Nilsson-Cantell, 1938: 24, fig. 1.

Material examined. ASIZCR000225, 1 specimen, Stn. CP164 (22°15.57’N, 120°35.56’E, 25 May 2002, depth: 60–90 m), CL 9.76 mm, CW 6.44 mm, PL 7.6 mm.

Diagnosis. Capitulum higher than wide; 15 white plates; subcarina present; rostrum large, well developed; inframedian latus diamond-shaped; rostrolatus quadrangular, umbo apical.

Description. Capitulum higher than wide, 15 fully calcified, white plates; tergum truncated, quadrangular, wider than high, occludent and basal margins slightly convex, umbo apical ( Fig. 1 B); scutum irregularlyshaped, occludent margin almost straight, tergal, lateral and basal margins convex, umbo subapical; upper latus pentagonal, tergal margin longest, apex produced over scutal tergal angle, umbo apical ( Fig. 1 B); inframedian latus diamond-shaped, umbo apical ( Fig. 1 B); rostrolatus quadrangular, umbo apical; carinolatus quadrangular, umbo apical ( Fig. 1 B); rostrum well developed, large, diamond-shaped; carina strongly bowed, umbo apical, roof wide, laterally convex; subcarina quadrangular ( Fig. 1 B). Peduncle long, with dense, fine scales ( Fig. 1 B). Maxilla bilobed, setae distributed into 2 main clusters ( Fig. 4 A); maxillule cutting edge with small notch close to apical region, cutting edge not straight, basal region below notch slightly extended; 2 long setae above notch,> 6 setae below notch,> 10 large setae along extended basal region ( Fig. 4 B); mandible with 6 teeth, first separated from remainder, inferior angle ending in single sharp seta ( Fig. 4 C); mandibular palp elongated, setae on superior and inferior margins and distally ( Fig. 4 D); labrum with cutting edge concave, smooth, teeth absent. Cirrus I separated from remaining cirri, rami unequal, outer ramus longer, 12-segmented, inner ramus shorter, 8-segmented ( Fig. 4 F); cirri II–VI with rami sub-equal; cirrus II with outer ramus 16-segmented, inner ramus 14-segmented ( Fig. 4 G); caudal appendage short, 1-segmented, apex with dense, short setae, appendage length <height of basal segment of pedicle of cirrus VI ( Fig. 4 E).

Distribution. South China Sea, Taiwan, the Philippines, Malay Archipelago, Arabian Sea. Remarks. This is a new record for Taiwanese waters.

Figures

FIGURE 1. Taiwanese deep-sea barnacles (right side view). A. Glyptelasma gigas, B. Euscalpellum rostratum, C. Arcoscalpellum truncatum, D. Tarasovium orientale, E. Trianguloscalpellum diota, F. Trianguloscalpellum hirsutum, G. Trianguloscalpellum regium, H. Trianguloscalpellum weltnerianum, I. Verum novazelandiae.

FIGURE 4. Euscalpellum rostratum. A. Maxilla, B. Maxillule, C. Mandible, D. Mandibular palp, E. Caudal appendage, F. Cirrus I, G. Cirrus II. Scale bars in µm, except F, G in mm.