A new species of Pseudoniphargus (Crustacea, Amphipoda, Melitidae) from an anchialine cave on the French Mediterranean coast

A new species of the stygobiont melitid amphipod genus Pseudoniphargus Chevreux, 1901 is described from an anchialine cave located on the inner shore of the Salses-Leucate coastal lagoon, on the French Mediterranean coast. The new species is distinguished from other members of the genus by the combined display of. 1) gnathopod II not Sexually dimorphic, with short carpus; 2) Outline of basis of pereopods V-VII sexually dimorphic, with both margins convex and with overhanging posterodistal lobe in male, whereas margins subparallel and posterodistal lobe present but not overhanging in female; 3) Uropod I protopod lacking basofacial robust seta; 4) protopod of uropod III sexually dimorphic, proportionaly more elongated in male; 5) exopod of male uropod III not strongly elongated (less than 12 times as long as wide), slightly upcurved and tapering; female exopod similar but shorter (about 8.8 times as long as wide); and 6) telson wider than long, with distal margin shallowly excavated and with two distal robust setae at each side. The relationships of this species are briefly discussed.