TAXONOMIC REVIEW OF THE GENUS PROBOLOMYRMEX MAYR, 1901 (FORMICIDAE: PROCERATIINAE) FOR THE NEOTROPICAL REGION
Aline Machado Oliveira, Aline Machado Oliveira, Rodrigo Machado Feitosa
Departamento de Zoologia, Universidade Federal do Paraná, Curitiba, Brasil.; Departamento de Zoologia, Universidade Federal do Paraná, Curitiba, Brazil
The ant genus Probolomyrmex is a member of the subfamily Proceratiinae, which comprises two other genera, Discothyrea Roger, 1863 and Proceratium Roger, 1863. Probolomyrmex is easily recognized by the combination of eyeless workers; antennal insertions exposed and located in the frontal region above of clypeus, suspended over the mandibles, and the second segment of gaster never bent ventrally towards the mesosoma. Probolomyrmex includes 26 species distributed over the tropics. In the Neotropical Region, only four species are known so far: P. boliviensis Mann, 1923, P. brujitae Agosti, 1995, P. guanacastensis O’Keefe & Agosti, 1998 and P. petiolatus Weber, 1940. Specimens of this genus are rarely collected, being underrepresented in scientific collections. The last revision of the genus in South America was published in 1994 by Agosti who recognized three species for the region. A fourth species (P. guanacastensis) was described four years later, by O’Keefe & Agosti (1998). After examining specimens received as loan from different institutions it was possible to propose a new delimitation of Neotropical species in the genus using as main criteria the proportion of the length of head and antennal scapes; presence of propodeal and petiolar projections; the shape of the ventral region of the petiole; shape of subpetiolar process; and presence of the projections on the antero-ventral region of the first segment of gaster. It was possible to recognize eight species, of which four were previously known and four are new species. We have produced a dichotomous key to species, distribution maps, high-resolution images and scanning electron microscopy imagens, allowing the access to the diagnostic characters of each species and updating the knowledge about the taxonomy of the genus. Finally, we are also preparing a phylogeny based on morphological characters, that will help us to understand the evolution of this genus in the Neotropical Region.