Elasmopus souillacensis, Chandani Appadoo, 2003

Chandani Appadoo, 2003, The Genus Elasmopus (Crustacea: Amphipoda: Melitidae) from Mauritius (Indian Ocean) with Description of Five New Species, Records of the Australian Museum 55, pp. 61-84 : 71-74

Elasmopus souillacensis n.sp.

Figs. 9, 10

Type material. HOLOTYPE: 3, 3.5 mm, unique specimen, from mixture of Amansia glomerata , Jania adherens and Sargassum densifolium, Souillac (20°31'S 57°30.7'E), 10 Feb. 2000, AM P60549.

Description. Male, 3.5 mm. Head, with subocular notch; eyes subround with clear ommatidia.Antenna 1, moderately setiferous; peduncle article 2, 0.7× article 1; article 3, 0.5× article 1; accessory flagellum 2-articulate; primary flagellum 13-articulate. Antenna 2, moderately setiferous, article 5, 0.9× article 4; flagellum 7-articulate. Mandible, palp article 2 twice as long as article 1, with 1 medial seta and 2 distal setae; article 3 falcate, 1.1× article 2, with comb row of setae and 3 long apical setae. Maxilla 1, inner plate with 2 terminal plumose setae, and several fine setae on lateral margin. Labium, with mandibular lobes acute; outer plate with a blunt stout seta on inner margin. Maxilliped, palp article 3 with a small distal protuberance. Gnathopod 1, coxa 1.2× as long as broad, anterodistal margin slightly produced, distal margin with short setae about 0.2× the length of coxa; basis 2.6× as long as broad; carpus subequal to propodus; propodus with few groups of setae on medial face, palm defined by a robust seta. Gnathopod 2, coxa 1.2× as long as broad, distal margin with short setae and a few long setae about one-third length of coxa; basis 2.5× as long as broad; carpus reduced, cup-shaped, 2.2× as broad as long; propodus 2.1× as long as broad, narrowing distally, posterior margin moderately setiferous, with a medial rounded process and a short, oblique palm; dactylus robust, medially expanded and about two-thirds length of propodus. Pereopods 3–4, coxa 1.8× as long as broad; basis 3.6× as long as broad; propodus posterodistal margin with 1 striate sabre seta and 1 normal robust seta; dactylus distally constricted. Pereopods 5–6, basis subquadrate, posterior margin almost straight, weakly crenulate and with short setae. Pereopod 7, basis subovoid, posterior margin weakly crenulate with short setae. Epimera 1–2, posterodistal margin produced into a weak tooth. Epimeron 3, subquadrate with a row of robust setae on the anterodistal margin. Uropod 1, peduncle 1.4× inner ramus; outer ramus 0.9× inner ramus. Uropod 2, peduncle subequal to outer ramus; outer ramus 0.9× inner ramus. Uropod 3, peduncle 0.8× rami; inner and outer rami subequal; inner ramus with robust setae on lateral margin and an apical bunch of robust setae and 1 slender seta; outer ramus with 3 groups of robust setae on the lateral margin and several robust and 2 long fine apical setae. Telson, tapered, cleft to 75% its length; lobes notched with outer tooth more produced than inner tooth; each lobe with 2 strong apical robust setae.

Female. Unknown.

Remarks. Elasmopus souillacensis differs from all other species of Elasmopus by the combination of: short setae on coxae 1 and 2, the shape of the male gnathopod 2, the subequal rami of uropod 3 and the tapered and notched telson.

Type locality. Souillac , Mauritius .

Distribution. Mauritius.

Etymology. The specimen is named after the type locality.