Lepechinella uchu J. L. Barnard 1973

Lepechinella uchu

DIAGNOSIS.–All dorsal teeth about half length of coxa 2, pereonite 1 with one tooth, pereonite 2 to pleonite 4 also with one tooth, no accessory teeth; body covered with thin setae; epimera 1–3 posteriorly convex, each with medium and sharp tooth posteroventrally, no facial rows of setae; rostrum thin, slightly curved, extending along 33 percent of article 1 on antenna 1, first cephalic tooth as long as rostrum, second tooth less than half as long as rostrum; mandibular palp article 3 nearly 3 times as long as article 1, article 2 twice as long as article 3; coxa 1 bifid nearly half its length, coxa 2 shorter than coxa 1, also deeply and slightly bifid asymmetrically, coxa 3 asymmetrically bifid, posterior limb half length of anterior limb, coxa 4 evenly, strongly and sharply bifid, coxa 5 with anterior lobe similar to one limb of coxa 4, posterior lobe forming small nodule, coxa 6 with weak and rounded anteroventral limb, sharply extended posteroventral angle, coxa 7 with sharp and strongly extended posteroventral angle; accessory flagellum elongate, 1–articulate; telson cleft about 63 percent its length, each lobe with one long apical spine and one long seta, apposing margins of lobes nearly straight; uropod 1 with immensely large and thick outer ramus, inner ramus only one-fifth as long as outer ramus, very thin; uropod 2 exceptionally small, inner ramus extending 33 percent along outer ramus; inner ramus of uropod 3 extending about 80 percent along outer ramus.

DESCRIPTION.–Mouthparts generally like those shown for Lepechinella occlo, new species, but upper lip more deeply and asymmetrically notched, mandible similar but palpar proportions as in diagnosis and article 3 with two apical setae and three subapical setae, mandibular lobes of lower lip stouter, inner plate of maxilla 1 with two setae, outer with ten spines, right palp apex with eight stout spines and one thin facial spine, left palp apex with seven thin spines and one thin facial spine, inner plate of maxilla 2 thin like that of L. raua, new species, inner plate of maxilliped thinner and curved, outer as illustrated; gills heavily folded basally. Largest specimen, female, 8.5 mm.

Medium-sized individual, 5.6 mm, sex unknown, Vema 15–49: First cephalic tooth as long as rostrum, length ratios of outer and inner rami of uropods as follows: uropod 1 = 85:13, uropod 2 = 32:9, uropod 3 = 47:37.

Juvenile, 3.1 mm, Vema 15–49: First cephalic tooth twice as long as rostrum, latter short, second cephalic tooth about 75 percent as long as first; article 6 of gnathopods 1–2 lacking posterior setae; inner rami of all uropods relatively shorter than in adult; urosomite 1 lacking ventral spine shown for adult.

HOLOTYPE.–AMNH, male, 7.6 mm.

TYPE-LOCALITY.–Vema 15–53, off Pacific Costa Rica, 09°23′N, 89°32′W, 3545 m, 23 November 1958.

MATERIAL.–Vema 15–49 (2), 15–53 (2).

DISTRIBUTION.–Pacific Costa Rica, 3545–3563 m.

Lepechinella ultraabyssalis Birstein and Vinogradova

Lepechinella ultraabyssalis Birstein and Vinogradova, 1960:156–159 figs. 7, 8.

DIAGNOSIS.–Pereonal teeth rudimentary, pereonite 1 with two vague humps, pereonites 2–4 with stronger hump, pereonite 5 to pleonite 4 with small to medium, sharp tooth, no accessory teeth; body with sparse dorsal setae; epimera 1–3 posteriorly convex, posteroventral tooth small, sharp, projecting, epimera with facial setae but no setal rows; rostrum straight, subconical, basally thick, extending about 40 percent along article 1 of antenna 1, first cephalic tooth about 67 percent as long as rostrum, second tooth slightly smaller than first; mandibular palp article 3 nearly 4 times as long as article 1, article 2 only 1.5 times as long as article 3; anterior coxae short and broad, coxa 1 slipper-shaped, not bifid, anterior extension narrow, coxa 2 broad basally, then abruptly narrowed to point, coxa 3 nearly rectangular, with weak anteroventral point and slightly concave ventral margin, coxae 4–5 weakly bifid, points sharp, coxa 6 with anteroventral point similar to coxae 4–5, rounded posteroventrally, coxa 7 weakly bifid, both limbs rounded; accessory flagellum “small, 1–articulate”; telson cleft only 40 percent its length, each lobe with long apical spine seta; inner ramus of uropod 1 reaching 67 percent along outer ramus; inner ramus of uropods 2–3 scarcely shorter than outer ramus.

DISTRIBUTION.–Pacific Japan, 6475–6571 m.