Present address: Department of Biology, Dalhousie University, 1355 Oxford Street, Halifax, NS, Canada B3H 4J1.
DNA barcoding reveals overlooked marine fishes
Article first published online: 21 APR 2009
© 2009 Blackwell Publishing Ltd
Molecular Ecology Resources
Special Issue: Special Issue on Barcoding Life
Volume 9, Issue Supplement s1, pages 237–242, May 2009
How to Cite
ZEMLAK, T. S., WARD, R. D., CONNELL, A. D., HOLMES, B. H. and HEBERT, P. D. N. (2009), DNA barcoding reveals overlooked marine fishes. Molecular Ecology Resources, 9: 237–242. doi: 10.1111/j.1755-0998.2009.02649.x
- Issue published online: 21 APR 2009
- Article first published online: 21 APR 2009
- Received 10 October 2008; revision received 17 November 2008; accepted 28 November 2008
- cryptic species;
- DNA barcoding;
With more than 15 000 described marine species, fishes are a conspicuous, diverse and increasingly threatened component of marine life. It is generally accepted that most large-bodied fishes have been described, but this conclusion presumes that current taxonomic systems are robust. DNA barcoding, the analysis of a standardized region of the cytochrome c oxidase 1 gene (COI), was used to examine patterns of sequence divergence between populations of 35 fish species from opposite sides of the Indian Ocean, chosen to represent differing lifestyles from inshore to offshore. A substantial proportion of inshore species showed deep divergences between populations from South African and Australian waters (mean = 5.10%), a pattern which also emerged in a few inshore/offshore species (mean = 0.84%), but not within strictly offshore species (mean = 0.26%). Such deep divergences, detected within certain inshore and inshore/offshore taxa, are typical of divergences between congeneric species rather than between populations of a single species, suggesting that current taxonomic systems substantially underestimate species diversity. We estimate that about one third of the 1000 fish species thought to bridge South African and Australian waters actually represent two taxa.