Una propuesta para diferenciar funcionalmente especies del género Pheidole (Formicidae)?

PARIS, CAROLINA I; SANCHEZ RESTREPO, ANDRES; GUASTAVINO, AN; AVALOS, ANDREA; HANISCH, PRISCILA E

Mendoza

Congreso; X Congreso Argentino de Entomología; 2018

IADIZA

The classification of ant communities in functional groups allows analyzing patterns of community composition and its response to disturbance. Pheidole? ant species are all included, a priori, in the functional group of ?Generalized Myrmicinae? i.e cosmopolitan sub-dominant ants, occurring in most habitats with rapid recruitment to, and successful defense of, clumped food resources. However, several species of Pheidole have different ecological roles and may differ in their response to natural and anthropic disturbances. Previous studies showed that morphological traits (MT) of ants are strongly related to their ecological role. Our aim was to explore dissimilarities between morphological traits of Pheidole species. We sampled ants along five transects of 100m, atOsununu Natural Reserve, Misiones; an area preserving 168ha of Paranaense rain forest. Every 10m, we placed a pitfall trap for 48hs and sifted 1m2 of litter to extract ants with mini-Winkler over 48hs. Opportunist hand collecting sampling was performed. We measured MT of workers related to thequantity of resources consumed and habitat complexity (body size), feeding behavior (head width and head, mandible and eye length), foraging speed (hind tibia and femur length) and sensory ability(scape length). Cluster analysis (Ward method) was performed to produce a functional dendrogram for major and minor castes separately. We collected 688 individuals but only those species with workers of both castes were analyzed (S= 6, n= 58). Pheidole oxyops workers clustered separately and showed the highest values of MT for both castes. This is in accordance with its scavenger and predatory feeding behavior, high speed locomotion and preference for nesting and foraging in less complex habitats (open areas and edges of forest). Majors of P. cornicula (unknown ecology) clustered with P. oxyops indicating similar ecological role. Pheidole rugatula, P. rudigenis, P. transversostriata and P. radowszkoskii grouped in two clusters due intermediate or low values of MT. Our results show that Pheidole species could belong to different groups according to its MT and suggest that the ecological role of species could be inferred by ecological knowledge of other species from the same group.