Genetic diversity, phylogeny and biogeography in the tadpole shrimp Triops granarius (Branchiopoda: Notostraca) in Qatar

The natural habitat of Qatar lacks permanent surface freshwater. Temporary ponds formed after heavy rains in the winter season are inhabited by the tadpole shrimp Triops granarius (Branchiopoda: Notostraca). In order to assess the molecular diversity of this species and to determine the relationship of Qatari populations with those from other regions, the sequences of 28S rRNA, 16S rRNA, and COI genes of individuals collected in five temporary pools were examined. Maximum likelihood phylogenetic analysis showed a high level of sequence uniformity at all three loci and indicates that the closest relatives of T. granarius in Qatar are from south Ural and northeastern Asia, including Mongolia, China, and Japan. This pattern is consistent with the geological evidence that T. granarius expanded more recently from North Africa to northeastern Asia through the Arabian land bridge. Lastly, the large genetic gap existing between the Qatar populations and their closest relatives supports the recognition of a new lineage.