Sargo Amarelo, a traditionally recognized hybrid between two species of Brazilian reef fishes

Abstract

Hybridization has been described in several families ofcoral reef fishes (Montanari et al. 2012), including grunts(genus Haemulon) (Rocha et al. 2008). Here, we report thepresence of a hybrid between two species of Anisotremusgrunts, the porkfish, A. virginicus, and the black margate, A.surinamensis, from Cabo Frio, Rio de Janeiro (23°S, 42°W).Interestingly, A. virginicus and A. surinamensis are notsister species (Bernardi et al. 2008), but both are commonin that region.On 1 December 2012, while collecting fish tissues formolecular studies at a local spearfishing tournament, weobserved one individual that showed typical morphologicaland coloration characteristics of both A. virginicus (goldlines along the body), and A. surinamensis (large bronzebody). DNA sequencing of that individual following pub-lished protocols (Tavera et al. 2012) showed that the mito-chondrial cytochrome oxydase 1 (CO1) was identical to A.virginicus, and the nuclear RAG2 gene displayed heterozy-gous peaks at all 6 fixed nucleotide positions that differbetween A. virginicus and A. surinamensis (Fig. 1)(GenBankaccessionnumbersKC844035–KC844036).The-se results are consistent with an F1 cross between these twospecies, with A. virginicus as a maternal lineage and thepresence of A. surinamensis in its paternal ancestry. Suchhybrids are not uncommon in the subtropical reefs of thesoutheasternregionofBrazil,wherefishermenrecognizethefish as a hybrid by its local name Sargo Amarelo ("yellowgrunt").