Barcoding the ants of the Iguazú National Park, a biodiversity hotspot in northeastern Argentina

HANISCH PRISCILA E.; LAVINIA OBLANCA PABLO DAMIÁN; TUBARO PABLO LUIS; SUAREZ ANDREW V.; PARIS CAROLINA I.

Guelph

Congreso; 6th International Barcode of Life Conference; 2015

University of Guelph

Background: Ants are a key component of terrestrial ecosystems because they provide several ecological services such as seed dispersal, organic matter decomposition and soil nutrient cycling. Here we assess, through the generation and analysis of DNA barcodes, the diversity of ants of the Iguazú National Park (INP) as part of a major project that aims to barcode the ants of Argentina. The INP constitutes a biodiversity hotspot located in northeastern Argentina with over 200 species of ants and represents one of the biggest remnants of the Atlantic Forest, which is a priority for conservation as it harbors 7% of world?s diversity. Results: We obtained 178 COI sequences from 332 individuals belonging to more than 100 species from over 30 genera. Unidentified species were not included. The mean intraspecific sequence divergence was slightly over 0.70%, being 23 times higher than the mean interspecific divergence (16.6%). After removing a few species with strikingly deep intraspecific divergence, the mean intraspecific divergence fell to 0.30%. There were more BINs (73) than species (67), with no BIN being shared by different species. Seven species showed two clearly differentiated barcode clusters, suggesting the possible presence of cryptic biodiversity at INP. The existence of these divergent intraspecific lineages was supported by high node support values in complementary phylogenetic analyses. Significance: Taxonomic keys for Neotropical ants are mostly incomplete and based almost exclusively on workers, precluding the identification of males and queens of most species. Increasing the reference barcode library for the ants of INP (and Argentina) will certainly help to identify these castes and to register morphological variability of Neotropical ants, which may eventually lead to the generation of new taxonomic keys. Lastly, our results support the biodiversity hotspot status of the Atlantic Forest and suggest that ant?s diversity in INP is currently being underestimated.