DNA-barcoding Decapoda and Stomatopoda from West-Africa

Abstract

Knowledge about species biology, distributions, and autecologies is based on accumulated information provided by identifying observers from diverse time periods and from sometimes somewhat isolated scientific cultures. Traditional taxonomic revisions bear witness of the inherent challenges of specimen identification and the efforts to obtain concordant species observations that actually refer to the same natural units. “Mislabelled” species is a growing concern in population management and food industries. There is also an emerging alertness in macro-ecology of bias in estimators of species occurrences and in biodiversity assessment and modelling due to misidentifications. Open access databases with DNA-barcodes are potentially powerful tools to discover conflicting identifications and may help in species recognition and in harmonizing the use of species taxonomies across research groups. Barcodes may also give taxonomists alerts about a need for integrative re-evaluation of taxa and their distributions. Such ideas are the background motivation for our DNA-barcoding of benthic animals from recent sampling on the West-African shelf conducted by the EAF-Nansen programme. We prepared 470 specimens of Decapoda and five Stomatopoda, in sum representing 133 identified species, for DNA-sequencing using the BOLD v3 system. Sequences were obtained from 351 samples, including 107 (80 %) of the identified species. The BOLD-system assigned the sequences to 113 BINS (RATNASTINHAM & HEBERT, 2013) of which 64 BINS were taxonomically concordant and 33 were singletons. Amongst 16 taxonomically discordant BINs, one was due to a previous record with a junior synonym, four due to identical sequences of subspecies taxa or identification to genus only. Interestingly, some of the discordant BINs, such as our sequences of the crab Menippe nodifrons (Menippidae) contained conspecific matches with West-Atlantic sequences in BOLD whereas another matching sequence from GenBank had been identified as a Pilumnidae. The most striking conflicting identifications in BOLD were observed with respect to the genus Macropodia, showing a need for taxonomic resolution and revision. Reference: RATNASTINHAM, S. & HEBERT, P.D.N. (2013) A DNA-based registry for all animal species: the Barcode Index Number (BIN) system. -- PLoS ONE, 8(7): e66213. doi:10.1371/journal.pone.0066213.