Orchestia magnifica Vecchi, 1931

Myers, Alan A. & Lowry, James K., 2020, A revision of the genus Orchestia Leach, 1814 with the reinstatement of O. inaequalipes (K. H. Barnard, 1951), the designation of a neotype for Orchestia gammarellus (Pallas 1776) and the description of three new species (Crustacea: Amphipoda: Talitridae Talitrinae), Zootaxa 4808 (2), pp. 201-250 : 230-231

Orchestia magnifica Vecchi, 1931

( Fig. 22 )

Orchestia magnifica Vecchi, 1931 , 62, figs 5–7.

Type locality. An oasis in Jalu (Gialo), Libya .

Description of adult male (12 mm).

Head. Eyes large. Antenna 1 short, not reaching beyond peduncular article 4 of antenna 2. Antenna 2 peduncular article 5 1.5 × length of peduncular article 4; flagellum subequal in length with combined length of peduncular articles 4 and 5, with 19 articles, final article cone shaped, with terminal cluster of imbricated setae. Labrum without epistome. Mandible left lacinia mobilis with 4 cusps. Maxilliped palp article 2 with distomedial lobe.

Pereon. Gnathopod 1 subchelate, coxa smaller than that of coxa 2; posterior margin of carpus and propodus each with lobe covered in palmate setae; propodus length to carpus length 1:1.5; propodus strongly triangular; dactylus shorter than palm. Gnathopod 2 subchelate; basis 2.0 × as long as broad, merus posterior margin with 3 setae; propodus pyriform, distal width 0.6 × proximal width; dactylus elongate, scythiform. Pereopod 7 basis posterior margin weakly serrate; merus weakly triangular, 2 × as wide distally as proximally; carpus pyriform, about 1.3 × as long as broad, anterior margin strongly convex, posterior margin proximally convex, distally concave; subequal in length with merus; propodus elongate, 1.3 × length of carpus.

Pleon. Uropod 3 peduncle only a little longer than broad, ramus moderately slender 2.0 × as long s broad, only a little shorter than peduncle, outer margin with 5 strong robust setae.

Female. Unknown.

Habitat. In the brackish water of an oasis.

Remarks. Orchestia magnifica is very close to O. mediterranea but differs in uropod 3. In O. magnifica , the ramus bears five strong marginal robust setae, whereas in O. mediterranea , the margin is naked or bears a single small seta.

Distribution. Libya. Jalu oasis, Cyrenaica ( Vecchi 1931).

Figures

FIGURE 22. Orchestia magnifica Vecchi, 1931, Gialo Oasis, Cirenaica (redrawn from Vecchi 1931).