DNA barcoding and ecological survey of the ants of Iguazu National Park: looking at the tip of the iceberg in a biodiversity hotspot

HANISCH PRISCILA E.; LIJTMAER DARÍO A.; TUBARO PABLO LUIS; SUAREZ ANDREW V.; PARIS CAROLINA I.; LAVINIA OBLANCA PABLO DAMIÁN; LEPONCE MAURICE

Kruger National Park

Congreso; Seventh International Barcode of Life Conference; 2017

International Barcode of Life

Background: Understanding patterns of species diversity can only beachieved by long-term research and the integration of taxonomical,ecological, and behavioral data. Here, we studied the diversity andecology of ants of Iguazu National Park (INP), Argentina, using sixsampling techniques. DNA barcodes were used to uncover crypticdiversity, test species/morphospecies delimitation accuracy, and linkunidentified male and queen specimens with their worker caste.Results: INP houses 195 described ant species and an additional49 morphospecies. Leaf litter sampling and pitfall traps were the mostefficient sampling methods, while surface baiting revealed the prevalenceof large predatory species at different times of the day. Comparingbaiting to other sampling methods provided information onspecies co-existence and the presence of possible dominance hierarchiesamong ant species. We obtained the DNA barcodes of 312 specimensfrom 124 species (51% of the ants of INP). Our analyses evidenceda clear barcode gap in all species but two, with an average distance tothe nearest neighbour of 15.75%, almost eight times larger than themean distance to the furthest conspecific (2.07%). Eighty-three percentof the sequence clusters obtained with different clustering algorithms(ABGD, RESL, TCS) matched the reference species or morphospecies,while 10% highlighted possible cryptic diversity. In terms of efficacy,this barcode library allowed a correct identification in more than 94%of the species/morphospecies, and to assign a species name to 69% ofthe unidentified males and queens. Significance: This study evidencesthat DNA barcodes are a valuable tool for identifying the antsof the Atlantic Forest, a global diversity hotspot. Furthermore, ourproject provides a framework for understanding the ecology and thetaxonomic diversity of the ants of this region, including the identificationof currently undescribed reproductive castes and the discoveryof possible cryptic species.