DNA reveal new invasive species of tiger shrimp Penaeus monodon (Penaeidae) along the world's largest mangrove region in the Brazilian Blue Amazon.

Bioinvasions represent a major environmental issue, particularly when they take place in biodiversity hotspots, such as mangrove ecosystems that serve as shelter for many marine species and fisheries resources. In this work, we used an integrative approach based on DNA and morphological analyses to identify individuals and the putative presence of cryptic diversity in the invasive tiger prawn (Penaeus monodon) along a mangrove area on the northern coast of Brazil, referred to as "Blue Amazon". A fragment of the mitochondrial cytochrome c oxidase subunit I (COI) gene was selected for DNA Barcode and associated with distance-based (ABGD-Automatic Barcode Gap Discovery) and probabilistic (GMYC-Generalized Mixed Yule Coalescent and bPTP-Bayesian Poisson tree processes) species delimitation methods. Furthermore, the maternal origin of collected specimens was tracked. The molecular analyses recovered two genetically divergent lineages (7.7%) within the tiger prawn, indicating the occurrence of two species of this bioinvader on the northern coast of Brazil. Even though no differences in external morphology were detected, both lineages could be differentiated by their internal structures. The molecular traceability of the origin of samples showed that lineages I and II shared haplotypes with specimens from 11 and nine countries, respectively, including a shrimp breeding center in Vietnam. This is the first record of two species of tiger prawn along the Brazilian continental shelf. These findings are useful to the development of effective management policies in a region of particular biological relevance.