Amigdoscalpellum torbenwolffi Zevina, 1981

Poltarukha, Oleg P. & Mel’Nik, Vyacheslav F., 2012, New records of deep-sea barnacles (Cirripedia: Thoracica: Scalpelliformes) from the Clarion-Clipperton region, Pacific Ocean, Zootaxa 3297, pp. 34-40 : 35-36

Amigdoscalpellum torbenwolffi Zevina, 1981

Figure 1

Amigdoscalpellum torbenwolffi Zevina, 1981a: 86 , fig. 8. — Zevina, 1981b: 287, fig. 217. — Young, 2007: 70.

Material examined. Mg-1214, 1 specimen, stn 122 (13°11.305’N, 134°30.305’W), 07 Aug. 2006, depth 4820m; Mg-1215, 1 specimen, stn. 8732 (13°.56392’N, 133°.61253’W), 31 Dec. 2010, depth 4867m.

Diagnosis. 14 fully calcified capitular plates without radiating lines. Inframedian latus triangular. Distance between carina and other capitular plates insignificant. Lateral faces of carina narrowing considerably from top to bottom. Peduncle covered by large scales.

Description. Capitulum white, elongated, bent in form of half moon; cuticle covering capitulum, with short, sparse setae. Capitular plates with thin growth lines, longitudinal ridges absent. Tergum large, triangular; umbo apical; occludent margin slightly convex. Scutum quadrangular; apex recurved, extending over tergum; carinal and basal margins convex. Carina regularly arched, roof flat, lateral margins narrow. Upper latus quadrangular; apex acute, slightly recurved; scutal margin distinctly concave, other margins almost straight. Carinolatus higher than wide, pentagonal; umbo a little above middle of carinal margin; plates contiguous under carina, interdigitating. Inframedian latus triangular, higher than wide; umbo apical, not reaching upper edge of neighbouring plates. Rostrolatus trapeziform, higher than wide, upper margin twice length of basal margin. Rostrum small, triangular. Peduncle short, approximately one quarter length of capitulum, covered by large scales. Labrum bullate, crest with row of small teeth. Labial palp acuminate, with few setae. Mandible with 3 teeth; 6 small acute denticles in lower angle. Maxilla I divided into 2 parts by small notch; 2 large setae above notch, group of medium-sized setae below. Maxilla II broad, covered with setae; maxillary gland projecting prominently. Cirrus I with unequal rami; outer ramus slender, longer, 12-segmented; inner ramus broader, short, 8-segmented; both rami covered by plumose acinaciform setae. Cirrus II with outer ramus 17-segmented, inner ramus 21-segmented. Cirrus III with outer ramus 16-segmented, inner ramus 18-segmented. Cirrus IV with outer ramus 17-segmented, inner ramus 18-segmented. Cirrus V with outer ramus 18-segmented, inner ramus 20-segmented. Cirrus VI with outer ramus 19-segmented, inner ramus 22-segmented; medial segments of cirrus VI clothed with 4 groups of setae on ventral margin, 3–4 setae at upper dorsal angle. Caudal appendage 5-segmented.

Distribution. Pacific Ocean: off eastern Australia (30°36’S, 169°22’E); Clarion-Clipperton region; depth 3460–4820m.

Remarks. This is a new record for the Clarion-Clipperton region of the Pacific Ocean.

Figures

FIGURE 1. Amigdoscalpellum torbenwolffi Zevina, 1981. A. Left side view, B. External view from rostral side, C. External view from carinal side, D. Labrum, E. Labial palp, F. Mandible, G. Maxilla I, H. Maxilla II, I. Caudal appendage.