Quadrimaera frater, Myers, A. A., 2014

Myers, A. A., 2014, Amphipoda (Crustacea) from the Chagos Archipelago, Zootaxa 3754 (1), pp. 1-31 : 8

Quadrimaera frater sp. nov.

( Figs 6 , 7 )

Type material. Holotype female, Great Chagos Bank, Brothers Island, outer reef, dead branching coral heads, 10 m. C. Head and H. Koldewey, 27.02.2012 ( OUMNH.ZC.2013.06.013). Paratype male, same data as holotype ( OUMNH.ZC.2013.06.014).

Etymology. frater = Latin, brother, relating to the type locality.

Description. Based on female holotype, 4.3 mm.

Head. Head with eye lobes rounded; eye of moderated size, rounded. Antenna 1 less than half body length; peduncular article 1 and 2 subequal in length; article 3 one quarter length of article 2; flagellum a little shorter than peduncle with 12 articles; accessory flagellum long, with 7 articles. Antenna 2 subequal in length with antenna 1; peduncular article 5 slightly shorter than article 4; flagellum longer than peduncular article 5 with 9 articles. Mandible palp with three articles; article 1 posterodistal margin with acute spine; article 2 longer than article 3; article 3 slender subovoid. Maxilla 1 inner plate with long terminal setae; palp 2-articulate.

Pereon. Gnathopod 1 coxa anterodistal margin produced, acute; carpus and propodus subequal in length; carpus anterior margin with shallow indentation; propodus palm evenly convex; dactylus fitting palm. Gnathopod 2 coxa subquadrangular; basis stout about 3 × as long as broad. anterodistal margin with two robust setae; carpus very reduced, cup-shaped; propodus enormous, palm convex, evenly scalloped, defined by strong spine; dactylus fitting palm. Pereopods 3–7 dactylus anterior margin with accessory spine. Pereopods 3–4 slender. Pereopod 5 basis slender. Pereopods 6–7 basis expanded, weakly serrate.

Pleon. Epimera 1–3 posterodistal margin with acute spine, increasing in size from epimeron 1 to epimeron 3. Uropod 1 with many robust setae; rami subequal and subequal in length with peduncle. Uropod 2 with many robust setae; inner ramus longer than outer and longer than peduncle. Uropod 3 missing. Telson fully divided, each lobe with two distal spines and two long robust setae.

Remarks. This species seems to be closest to Q. schellenbergi (Ruffo, 1938) from the Red Sea but differs in having antenna 1 and 2 subequal in length (antenna 1 much longer than antenna 2 in Q. schellenbergi ), in the elongate article 2 of the mandible palp and by the acute spine on epimeron 2

Habitat. Dead branching coral heads.

Distribution. Known only from Chagos archipelago.

Figures

FIGURE 6. Quadrimaera frater sp. nov., female, holotype, 4.3 mm, Great Chagos Bank.

FIGURE 7. Quadrimaera frater sp. nov., female, holotype, 4.3 mm, Great Chagos Bank.