“Lepidepecreoides xenopus, Brnrd.
Barnard, 1931, p. 426.
Occurrence: 1. St. 177. South Shetlands. 1 ♀11 mm.
2. St. 181. Palmer Archipelago. 1 ♂ 9 mm. Type.
3. St. WS 33. South Georgia. 1 juv. 4.5 mm.
Description. Integument indurated; when seen by transmitted light it has a honeycomb reticulation, but when seen in an oblique reflected light each hexagonal mark seems to have a raised border so that the integument appears strongly scabrous. Head with antero-lateral angle quadrate. No eyes. Peraeon moderately compressed, scarcely or feebly carinate, but dorsal profile indented at junctions of segments, especially posteriorly. Side-plates deep ; 1-4 deeper than their segments, setulose on their anterior margins, 1-3 oblong, with a denticle at postero-inferior angle, 4 also oblong with the whole hind margin excavate for the reception of the deep 5th side-plate, which is very solid in front portion but with a crescentic hollowing posteriorly for reception of znd joint of peraeopod 3, hind margin and lower part of anterior margin setulose; side-plate 6 slightly deeper than long, with lower margin excavate between anterior and posterior lobes ; side-plate 7 longer than deep, ovoid ; hind margins of 6 and 7 setulose. On segments 5, 6 and 7 just above the junction of the side-plates there is a rounded nodulose prominence. Pleon carinate, dorsal profile on each of segments 1-3 undulate, carina ending on segment 3 in a triangular tooth-like projection; segment 4 with a strong slender upstanding tooth ; segment 5, very short; postero-inferior angles of segments 1-3 rounded. Segments 1-3 each have a lateral prominence which is rather indefinite, the most projecting part being in line with the prominences on peraeon segments 5-7. Telson twice as long as basal width, cleft to base, lobes tapering to acute apices, each with a terminal spinule.
Antenna 1, peduncle stout but not carinate, the 1st and 2nd joints scabrous, 3rd very short, flagellum 6-jointed, 1st joint large, with regular brush of plumose setae along lower margin, 2nd-6th joints much smaller, accessory flagellum 2-jointed, as long as 1st flagellar joint, 1st joint long, 2nd very short. Antenna 2 slender, 4th and 5th joints subequal, flagellum 7-jointed.
Epistome straight in profile, not expanded; upper lip considerably gibbous. Mouth parts as in Lepidepecreopsis (Stephensen, 1925, p. 120, fig. 33). Lower lip with lobes apically rounded as in Lepidepecreum. Spines on apex of outer plate of maxilla I very stout; inner plate with two setae. The short stout spines on apex of palp of maxilla 1 and on inner margin of outer plate of maxilliped very regular, as in Stephensen's figures.
Gnathopod I moderately slender; 6th joint about two-thirds length (upper margin) of 5th, widening slightly to the oblique palm, a spine at the defining angle, finger overlapping palm. Gnathopod 2, 6th joint ovoid, broader than in any of the allied genera, palm convex, slightly projecting, but not chelate, finger overlapping palm.
Peraeopods 1 and 2 armed with a few rather long outstanding setae, dactyl elongate, two-thirds length of 6th joint (cf. Lepidepecreopsis). Peraeopod 3, 2nd joint remarkably thick, quadrangular, angularly expanded on both anterior and posterior margins, the proximal part of anterior margin with a few spinules, the distal part and the whole posterior margin with short plumose setae, 3rd, 4th and 5th joints also with plumose setae as well as a few longer simple setae, dactyl slender, two-thirds length of 6th joint. In the juvenile the 2nd joint is more oblong than square and the hind margin is produced in a strong straight spine. Peraeopods 4 and 5, znd joints not abnormally thick, ovate, hind margin strongly serrate and with short plumose setae, armature of other joints as in peraeopod 3; peraeopod 4 slightly longer than 5.
Uropods 1 and 2, rami subequal, acuminate, sparsely spinose. Uropod 3 extending as far back as uropod 1 and slightly beyond apex of telson, rami lanceolate, 2nd joint of outer ramus well developed, inner margin of both rami with long plumose setae.
A single accessory branchia on both segments 5 and 6.
Remarks. The extraordinarily shaped 2nd joint of peraeopod 3 fits within the hollowed portion of the 5th side-plate when the limb is folded back. The whole animal was covered with very fine particles of foreign matter due to the muddy nature of the bottom ; and the setulose margins of the side-plates would seem to be for the purpose of excluding such foreign matter from penetrating between them.”
(Barnard, 1932: 62-64)
