A New Species of Freshwater Amphipods Echinogammarus (Amphipoda, Gammaridae) from Algeria

Several samples of amphipods were obtained from six stations in the upper reach of the Youkous Stream, near Hammamet. This study describes a new species, Echinogammarus monodi n.sp., differing from other Echinogammarus species in the length of the first antenna, the setation of the third article of the mandibular palp (bearing three rows of A-setae and two rows of B-setae), the merus and carpus of pereopods 5 with long setae only, and the exopodite of uropod 3 with numerous groups of long simple setae. A full description of the new species and information about its distribution is given in this paper.