Population genetic partitions and phylogeography of Atlantic reef zones: Rypticus saponaceous and Epinephelus adscensionis (Perciformes: Serranidae)

Joel L. Carlin* and Brian W. Bowen
Department of Fisheries and Aquatic Sciences, IFAS, University of Florida, 7922 NW 71st Street, Gainesville, FL 32653-3071 Phone: (352) 392-9617 Fax: (352) 846-1088 E-mail: joelcarlin@hotmail.com

The soapfish Rypticus saponaceous and rock hind Epinephelus adscensionis are serranid species associated with reef habitat throughout the tropical Atlantic Ocean. Populations of these nonmigratory fishes are separated by discontinuities (ocean expanses and soft bottom habitat) between the major Atlantic biogeographic provinces of Brazil, the Caribbean, and West Africa. We sequenced a segment of the mitochondrial cytochrome b gene from individuals collected in the northeast Caribbean, Brazil, Ascension Island (mid-Atlantic ridge) and Sao Tome (Gulf of Guinea). Fixed differences (reciprocal monophyly) distinguished soapfish in the East versus West Atlantic, and rock hind in the Caribbean versus elsewhere in the Atlantic. Other locations were distinguished by significant haplotype frequency shifts. Overall, a substantial portion of genetic diversity in these species is distributed across biogeographic zones, indicating that at least some management issues must be considered on this geographic scale.