COI (cytochrome oxidase-I) sequence based studies of Carangid fishes from Kakinada coast, India M. Persis Æ A. Chandra Sekhar Reddy Æ L. M. Rao Æ G. D. Khedkar Æ K. Ravinder Æ K. Nasruddin Received: 10 August 2008 / Accepted: 24 September 2008 / Published online: 12 October 2008 Ó Springer Science+Business Media B.V. 2008 Abstract Mitochondrial DNA, cytochrome oxidase-1 gene sequences were analyzed for species identification and phylogenetic relationship among the very high food value and commercially important Indian carangid fish species. Sequence analysis of COI gene very clearly indi- cated that all the 28 fish species fell into five distinct groups, which are genetically distant from each other and exhibited identical phylogenetic reservation. All the COI gene sequences from 28 fishes provide sufficient phylo- genetic information and evolutionary relationship to distinguish the carangid species unambiguously. This study proves the utility of mtDNA COI gene sequence based approach in identifying fish species at a faster pace. Keywords Carangidae Á Cytochrome oxidase-I (COI) Á mtDNA Gene Á Interspecific Á Intraspecific Á Taxonomy Introduction The family Caringidae comprises mainly 36 species having high commercial value. These are most delicious food fish available along Indian coast [1, 2]. They are highly appreciated table fishes for internal and export markets, fetching a very high price. The carangids are categorized under five main sub groups as black pomfrets, queen fishes, trevallies, scads, and pompanos. The group has emerged as one of the important resources especially in mechanized sector, but also exploited by motorized and non-mecha- nized sector [3]. Traditionally carangid fishes are identified based on visible morphological, meristic, and anatomical characters. Many times taxonomic ambiguities exist due to morpho- logical and meristic similarities. Modern taxonomic work includes analysis of a host of other traits, including anat- omy, physiology, behavior, genes, and geography, yet morphological traits remain the cornerstone. FishBase citations include many synonyms which indicate ambigu- ities in carangid species identification [2]. Accurate species identification is very important in case of morphological similar species for fisheries management, biodiversity studies, and population dynamics. The increasing loss of biodiversity globally has led to numerous proposals to intensify efforts to produce a census of all biological diversity and to modernize taxonomy. Traditional morphology-based taxonomic procedures are time consuming and therefore a multidisciplinary approach to taxonomy that includes morphological, molecular, and distributional data is essential. Hebert et al. have shown that the analysis of short, standardized genomic regions (DNA barcodes) can discriminate morphologically recog- nized animal species [4, 5]. In particular, the mitochondrial gene cytochrome-C oxidase subunit 1 (CO1/COX 1) can M. Persis Á A. Chandra Sekhar Reddy State Institute of Fisheries Technology, Kakinada, Andhra Pradesh, India L. M. Rao Department of Zoology, Andhra University, Visakhapatnam, Andhra Pradesh, India G. D. Khedkar (&) Aquacuture Research Laboratory, Dr. Babasaheb Ambedkar Marathwada University, P.O.B. 02, Aurangabad, Maharashtra 431 021, India e-mail: gdkhedkar@gmail.com K. Ravinder Center for Cellular and Molecular Biology, Hyderabad, Andhra Pradesh, India K. Nasruddin Bioserve Bio Technologies India Pvt. Ltd., Hyderabad, Andhra Pradesh, India 123 Mol Biol Rep (2009) 36:1733–1740 DOI 10.1007/s11033-008-9375-4