Diversity and distribution patterns of large branchiopods (Crustacea: Branchiopoda) in temporary pools (Iran)

A survey on the distribution and status of large branchiopod crustaceans (Branchiopoda: Anostraca, Notostraca, Conchostraca) in Iran was carried out from spring 2008 to summer 2011 with the purpose of providing a systematic contribution to the knowledge of these crustaceans in the region. Data from literature on Iranian large branchiopods are briefly reviewed, and field surveys allowed us to add new data on their presence and co-occurrence in the area. Eleven large branchiopod species were collected, including five Anostraca, three Notostraca and three Conchostraca species. Anostraca have been recorded previously from Iran, but all of the Conchostraca (Leptestheria sp., Caenestheriella sp. and Cyzicus sp.) and Triops granarius are new records. Species richness was correlated to pool size and salinity. Diversity analysis revealed that large-size low-salinity (0.5-3 gl−1) pools housed more species than the other pool categories. This may suggest strong species-sorting mechanisms and possibly monopolization of resources in small saline pools. Most of the observed large branchiopod species are threatened or remain data deficient due to inadequate knowledge of their distribution. Local extinction risks are high for - species with one or two populations due to consecutive years of drought.