Abstract
DNA barcoding is a useful tool for the identification and potential discovery of new species. In this study, DNA barcoding was employed by sequencing the mitochondrial cytochrome oxidase subunit I gene (COI) to characterize the genetic diversity of 12 shrimp species inhabiting Turkish coastal waters and, when possible, to compare with the genetic data available from different parts of the Mediterranean and eastern Atlantic. This study also comprises the first DNA barcoding study performed in the Turkish Seas using COI. A total of 40 shrimp specimens were collected and analyzed from 9 sites. Generally, the barcoding gap criterion was successful at identifying species; hence COI appeared to be a good marker of choice for DNA barcoding in this group. Out of the 12 species investigated, five were barcoded for the first time. In six species two intraspecific clades were retrieved after the analyses. The results suggest the presence of cryptic diversity in a genetically understudied marine area, Turkish coastal waters, and further investigation in these species using population genetics, taxonomic approaches and nuclear markers is likely to result in designation of new species.