DNA barcoding and ecological survey of the ants of the southern Atlantic Forest: looking at the tip of the iceberg in a biodiversity hotspot.

SUAREZ, A.; PARIS, C.; LAVINIA OBLANCA, P. D,; LEPONCE, M.; HANISCH; LIJTMAER, D. A.; TUBARO, P. L.

Curitiva

Congreso; XXIII Simposio de Mirmecología - An International Ant Meeting; 2017

Sociedad Brasileira de Entomología y Universidad Federal de Paraná

Understanding patterns of species diversity can only be achieved by long-term research and the integration of taxonomical, ecological and behavioral data. Here we studied the diversity and ecology of ants of southern Atlantic Forest, in the Misiones province, Argentina with special collection effort in the Iguazú National Park (INP), where be used six sampling techniques. DNA barcodes were used to uncover cryptic diversity, test species/morphospecies delimitation accuracy, and link unidentified male and queen specimens with their worker caste. Results: INP houses 195 described ant species and an additional 49 morphospecies. Leaf litter sampling and pitfall traps were the most efficient sampling methods, while surface baiting revealed the prevalence of large predatory species at different times of the day. Comparing baiting to other sampling methods provided information on species co-existence and the presence of possible dominance hierarchies among ant species. We obtained the DNA barcodes of 312 specimens from 126 species (51% of the ants of INP). Our analyses evidenced a clear barcode gap in all species but one, with an average distance to the nearest neighbor of 15.74%, almost nine times larger than the mean distance to the furthest conspecific (1.83%). Ninety-two percent of the sequence clusters obtained with different clustering algorithms (ABGD, RESL, TCS) matched the reference species or morphospecies, while the remaining 8% highlighted possible cryptic diversity. In terms of efficacy, this barcode library allowed a correct identification in more than 96% of the species/morphospecies, and to assign a species name to 70% of the unidentified males and queens. Significance: This study evidences that DNA barcodes are a valuable tool for identifying the ants of the Atlantic Forest, a global diversity hotspot. Furthermore, our project provides a framework for understanding the ecology and the taxonomic diversity of the ants of this region, including the identification of currently undescribed reproductive castes and the discovery of cryptic species.