Abstract
A new amphipod species, Dikerogammarus istanbulensis sp. nov., is described. Specimens were collected from a reservoir, near Silivri district, Istanbul province, Turkey. The new species is similar to Dikerogammarus bispinosus Martynov, 1925 except forthe presence of setae on inner surface of basal segment of pereopod 7 in both sexes and absence of long setae on the ventral side of second peduncle segment of antenna 1. In addition, epimeral plate 2 has many setae along the ventral margin in both sexes. A detailed morphological description and illustrations of the new species are given. Differences between the new species and related species are discussed. An identification key for the genus Dikerogammarus is presented.
NSTL