Epimeria (Drakepimeria) vaderi, d’Acoz & Verheye, 2017

d’Acoz, Cédric d’Udekem & Verheye, Marie L., 2017, Epimeria of the Southern Ocean with notes on their relatives (Crustacea, Amphipoda, Eusiroidea), European Journal of Taxonomy 359, pp. 1-553 : 63-65

Epimeria (Drakepimeria) vaderi subgen. nov. Coleman, 1998

Epimeria vaderi Coleman, 1998b: 215–224 , figs 1–6.

Epimeria vaderi – Coleman 2007: 55, figs 31a–b, map 14 (circle).

Description

Description based on the figures of Coleman (1998b).

ROBUSTNESS. More robust than most Drakepimeria . Rostrum: medium-sized, just overreaching tip of article 1 of peduncle of antenna 1 (teeth excluded), weakly curved, sharp-tipped in lateral view.

EYE. Very large, elliptic.

PEREION–PLEOSOME TOOTH PATTERN. Pereionites 1–3 without any trace of mid-dorsal tooth, without dorsolateral protrusions; pereionite 2 slightly narrower than pereionite 1; pereionite 4 with very faint posterodorsal bump and no dorsolateral protrusions; pereionite 5 to pleonite 2 with broad and low, regularly curved, dorsolateral tooth, and pair of small posterodorsal swelling or teeth; on pleonites 1–2 a second pair of (a bit smaller) dorsolateral teeth is observed between the mid-dorsal tooth and the main

pair of dorsolateral teeth; pleonite 3 with large subacute mid-dorsal tooth bearing a shallow but long median concavity.

COXAE 1–3. Carinate and distally sharp.

COXA 4. Anterodorsal border proximally nearly straight (inconspicuously convex) and unusually long, of curvature gradually increasing downwards and followed by anteroventral border without any angular discontinuity or visible transition; posteroventral border weakly convex and short; coxa scarcely projecting forward; ventral tooth narrowly triangular, not long, apically subacute; lateral carina without tooth or angularity, not projecting laterally, carina very close from margin of coxa at its deepest point.

COXA 5. Without laterally projecting carina (hence scarcely visible in dorsal view), with posteroventral corner produced into a blunt tooth oriented backwards.

COXA 6. With mid-sized, blunt, triangular, lateral tooth pointing obliquely backwards (scarcely projecting laterally); posteroventral corner produced into a rounded lobe pointing downwards (posterior margin nearly straight).

COXA 7. With ventral border distinctly curved, with posterior border, their convergence forming a blunt angular discontinuity; surface of coxa posteriorly without low carina oriented in the dorsoventral axis.

EPIMERAL PLATES 1–3. Posteroventral angle produced into a small but sharp tooth.

UROSOME TOOTH PATTERN. Urosomite 1 with very sharp narrow triangular process pointing upwards; urosomite 2 without pair of small posterior dorsolateral teeth pointing upwards.

TELSON. Cleft on 0.25; tips of lobes subacute, slit fairly broad and V-shaped.

PEDUNCLE OF ANTENNA 1. Article 1 with short lateral medial and ventral teeth reaching the base of article 2 [some teeth apparently duplicated]; article 2 with medium-sized lateral and medial teeth reaching about tip of article 3, with ventral tooth very reduced to a denticle [some teeth apparently duplicated]; article 3 with small ventral tooth, about as long as article itself.

GNATHOPODS 1–2. Carpus and propodus of normal slenderness; propodus not narrowing distally, palm distinct.

PEREIOPODS 5–7. Merus, carpus and propodus very stout; basis of pereiopods 5–6 of normal width, with posteroproximal process rounded and distinctly protruding, with posterodistal tooth strong and broad; basis of pereiopod 7 very broad with posterodistal tooth forming a squared angle, not followed more proximally by small concavity, directed posteriorly.

Body length

19 mm.

Distribution

RV Polarstern, PS12, stn 231, Elephant Island. Coleman (1998b) gives the following coordinates for station 231: 61°03.8ʹ S, 54°37.6ʹ W, 332 m, and Fütterer (1988) the following ones: 61°03ʹ S, 54°45ʹ W (start position), 331 m.

Remarks

Superficially similar to the sympatric and larger E. leukhoplites sp. nov. See account on E. leukhoplites sp. nov. for differences.