Identification and taxonomy of sea cucumbers (Holothuria) in Persian Gulf

The sea cucumbers of the genus Holothuria are important species in Asia. In present study in the Persian Gulf aimed to identify Holothuria species and investigate their relationships based on morphological and 16S rRNA molecular data. 30 specimens were collected from northern Persian Gulf coasts of Dayer (Bushehr Province) and Lengeh (Hormozgan Province). Based on ossicles morphology, three species were identified. DNA was isolated using CTAB method. Thereafter, 16S ribosomal RNA gene amplification was performed using universal primer and consequently PCR product was sequenced. Sequencing result was analyzed and identified in NCBI database using BLAST. 17 sequences of mitochondrial DNA of 16S rRNA gene (393bp length) were obtained after modification and alignment. The phylogenic tree of mentioned species showed a monophyletic group. The three identified species include Holothuria (Thymiosycia) arenicola, Holothuria leucospilota and Holothuria parva. Holothuria arenicola was found in high support in the sister clade of H. arenicola from China. Despite 7% genetic distance, no morphological differences were observed between H. arenicola with similar species.