DNA Barcoding and species diversity of Oligochaeta in Jajrood River

Generally, oligochaetes as a well-known group of earthworm invertebrates with global distribution have been considered from two Ecological and taxonomical point of view. Species diversity of oligochaetes was investigated in Jajrood River, Caspian Southern basin, Iran. This research began in autumn and winter and specimens were collected from 7 collecting stations using a kick sampling approach across the river. Today, the use of modern methods, including genetic markers, provides a more accurate understanding of the species To evaluate the diversity and facilitate identification of the oligochaete species, both DNA barcoding, using the mitochondrial gene cytochrome c oxidase subunit I (COI), and morphological identification keys were utilized. As a result, five species including Tubifex tubifex, Tubifex sp., Eiseniella tetraedra, Eisenia fetida, and Eisenia sp. belonging to the families Lumbricidae and Naididae were identified. The results showed E. tetraedra to be the most abundant species, which consists of four divergent lineages in this river system.