Diversity of sea lice (Copepoda: Caligidae) parasitic on marine fishes with commercial and aquaculture importance in Chamela Bay, Pacific coast of Mexico by using morphology and DNA barcoding, with description of a new species of Caligus.

The occurrence of parasitic copepods of the family Caligidae on wild and cultured marine fishes from Chamela Bay, on the Pacific coast of Mexico, is reported. A total of 16 species of Caligus and 1 species of Lepeophtheirus were found on 19 wild fish species. The description of Caligus chamelensis n. sp. parasitizing Kyphosus elegans is presented. Among the species of Caligus reported here, Caligus serratus is the most common since it was found infecting 11 fish species. On cultured fish, Lutjanus gutattus and L. peru, only one species of Caligus, C. sclerotinosus was collected. DNA barcodes [mitochondrial cytochrome c oxidase subunit I (COI) gene sequences] were obtained for the majority of the sea lice species herein reported. The molecular analyses support the recognition of the new species and suggest that neither Caligus nor Lepeophtheirus are monophyletic. COI is shown to be a good candidate for parasitic copepod species identification, although a more robust reference database is needed to expand our ability to accomplish a molecular identification.