LAUSR

Abstract Cephalopods (cuttlefishes, squids and octopuses) are highly commercially important marine organisms in the Andaman Islands. DNA barcoding is an effective tool used for identification of individuals at the lowest taxon (species) level and is been widely used for the detection of structural ambiguity of several organisms. In the present study, DNA fragments of mitochondrial cytochrome c oxidase 1 (COI) gene comprising 658 base pairs (bp) were amplified by employing forward LCO 1490 and reverse HCO 2198 primers. Amplified sequences were trimmed to length of 583 bp for complete alignment. The average nucleotide frequencies were studied for eight individuals belonging to seven species (Sepia pharaonis, Sepia aculeata, Uroteuthis duvauceli, Sepioteuthis lessoniana, Octopus cyanea, Abdopus aculeatus, Octopodidae sp.) as A = 29.82%, T = 35.35%, G = 15.33% and C = 19.35%, respectively. Genetic studies revealed that the eight individuals of Coleoid cephalopods belonged to three taxonomic groups viz, (Sepioidea, Myopsida and Octopoda) under different families (Sepiidae, Loliginidae, Octopodidae).