DNA barcode reveals high cryptic diversity in the commercially important Penaeini shrimps (Decapoda, Penaeidae)

The inability to precisely identify biological species has direct impacts on conservation efforts, which is especially true among taxa of great commercial interest such as representatives of the Penaeini tribe. Those shrimp supply more than half of the global demand for crustaceans and have important functional roles in ocean ecosystems. Recent systematic studies suggest that the diversity of taxa within Penaeini is underestimated, and there are controversial taxonomic classifications. In this work, we used phylogenetic and phylogeographic approaches to assess the genetic diversity and evolutionary of representatives of the Penaeini tribe, focusing on the mitochondrial cytochrome oxidase subunit I gene. A total of 1680 COI sequences from 24 species were accessed on the Bold Systems platform. We detected several identification errors and synonyms among the 15 taxa of the tribe, principally within the genus Penaeus. Phylogeographic analyses allowed the identification of highly structured populations within several ecoregions of the Atlantic (19), Indian (16), and Pacific (10) oceans. The delimitation methods (GMYC, bPTB, and BINs) suggest are cryptic species such as Fenneropenaeus indicus (2 MOTUs), Litopenaeus vannamei (2 MOTUs), Penaeus monodon (3 MOTUs), and P. semisulcatus (4 MOTUs). The highest cryptic diversity concentration was found in the Indo-West Pacific region, suggesting it as the center of origin for the tribe. Our data provide important information that could subsidize management actions and guarantee the long-term maintenance of those lineages and their stocks.