A new species of snook, Centropomus (Teleostei: Centropomidae), from northern South America, with notes on the geographic distribution of other species of the genus.

Centropomus irae sp. nov. (Centropomidae) is described from two localities in the state of Amapá, northern Brazil. The new species differs from all its congeners by the typically brown-colored lateral line, the relatively smaller mean interorbital width (4.1% of SL vs. 5.2-6.9%), mean snout length (8.9% of SL vs. 9.8-11.1%), mean diameter of the orbit (4.5% of SL vs. 5.4-7.3%), and mean mandible length (15.7% of SL vs.19.9-21.6%). The new species can also be distinguished from the similar Centropomus undecimalis by the number of scales around the caudal peduncle (18-23, usually 19-21, vs. 22-28, usually 24-27). With Centropomus irae sp. nov., seven species of the genus are now known to occur in the western Atlantic. The distribution of Centropomus in Brazilian waters is updated and a key to the species of this genus is presented. [Zoobank URL: urn:lsid:zoobank.org:act:3D497B38-48A5-4A6E-B377-6D57E82D4DE4[.

Molecular data indicate the presence of a novel species of Centropomus (Centropomidae - Perciformes) in the Western Atlantic.

Centropomus undecimalis is distributed in the coastal waters of the western Atlantic between North Carolina and São Paulo, although very little is known of the genetic structure of its populations. Here, 148 C. undecimalis samples were obtained from six sites in the southwestern Atlantic, representing the Brazilian distribution of this species. Segments of three mitochondrial (Cytb, COI and 16S) and one nuclear (IGF1) gene were sequenced. The results of all analyses indicated the presence of a previously undetected lineage of Centropomus in the northern extreme of Brazil (Amapá) in the region of the Oiapoque estuary. This taxon is genetically distinct from all 12 recognized species of Centropomus. The populations from the Brazilian states of Pará, Maranhão, Ceará, Rio Grande do Norte, Rio de Janeiro and São Paulo were genetically similar to C. undecimalis from coastal areas of the Caribbean and USA. Nucleotide divergence between C. undecimalis and the new Oiapoque taxon are greater than or similar to those found between a number of valid Centropomus species. The estimated time of divergence between C. undecimalis and the new taxon is approximately 2 millionyears. The findings of the present study emphasize the need for a thorough taxonomic revision of this genus.