The biodiversity of subterranean amphipods of genus Niphargus in Iran with new record of N. hosseiniei

The members of the subterranean genus Niphargus Schiödte, 1849 live in subterranean waters or waters related to subterranean environments, such as springs. This group is one of the most species-rich genera (more than 300 species and subspecies) among freshwater amphipods in the world, distributed in the Western Palearctic. Iran has been recognized as the easternmost border of the genus Niphargus. Until now, there have been 17 species recorded from Iran; of these only one species was found outside Iran (N. valachicus), all other species are endemic to the country. In this study, the diversity and distribution of the Iranian niphargids are surveyed and contributions are made to diagnostic characters for each species and one new record of N. hosseiniei in Bilvar village in Kermanshah Province is reported. The distribution map of species localities were created using Arc GIs. Noteworthy, most of the Iranian species were described during the past five years and additional species descriptions can be expected to the subterranean fauna of Iran in a near future.