DNA barcoding of genus Metapenaeopsis (Decapoda: Penaeidae) and molecular phylogeny inferred from mitochondrial and nuclear DNA sequences

Metapenaeopsis Bouvier, 1905 is the most diverse genus within Penaeidae. Metapenaeopsis shrimps exhibited subtle morphological differences, which make identification a difficult task based on taxonomic keys alone. In this study, we carried out DNA barcoding and phylogenetic analyses to examine taxonomy and phylogeny of genus Metapenaeopsis based on mitochondrial (COI) and nuclear (PEPCK and NaK) genes. Despite limited performance of DNA barcoding in delineating Metapenaeopsis shrimps, it questioned the taxonomic status of the two subspecies, Metapenaeopsis mogiensis intermedia and Metapenaeopsis mogiensis mogiensis, as well as three separate species: Metapenaeopsis provocatoria longirostris, Metapenaeopsis quinquedentata and Metapenaeopsis velutina. The major pattern of relationships between all studied taxa of Metapenaeopsis was similar across all analytical methods in which species with one-valved petasma were genetically distinct from those with two-valved petasma. As expected from morphology, the remaining species with stridulating organ constituted a strongly supported clade. In contrast, a paraphyletic clade was resolved for species without stridulating organ which contradicts Crosnier's morphological classification scheme for Metapenaeopsis. Overall, the present molecular data indicated that the shape of petasma and stridulating organ were both phylogenetically significant morphological characters for this genus, adding further evidence for the Crosnier's proposal. (C) 2015 Elsevier Ltd. All rights reserved.