First Record of the Dolichoderine Ant Genus Gracilidris Wild & Cuezzo (Hymenoptera: Formicidae) from Southern Brazil

ABSTRACT - The dolichoderine ant species Gracilidris pombero, sole representative of the genus, is recorded for the first time in southern Brazil. Until now, the species was known only for the open fields of the South American dry diagonal and for a single locality in the Colombian Amazon. The specimens reported here were collected with pitfall traps in grasslands of the Pampa biome, Rio Grande do Sul state, Brazil. This record represents the southernmost occurrence for the genus, extending its distribution in approximately 450 km to the south in the Neotropics and in almost 1,150 km to the south in Brazil

Additions to the taxonomy of Pheidole (Hymenoptera: Formicidae) from the southern grasslands of Brazil

The ant genus Pheidole is the most species-rich lineage of ants in the world and one of the dominant organisms in tropical regions. However, the knowledge of Pheidole diversity in the southern half of the Neotropical Region is fragmentary. Here, we offer contributions to the Pheidole taxonomy considering the species that occur in the grassland formations of South Brazil. The following species are revived from synonymy: P. idiota Santschi rev. stat., P. obscurior Forel rev. stat., P. paranana Santschi stat. rev. et n. stat. and P. strobeli Emery rev. stat. The following synonyms are proposed: P. idiota (= P. laticornis Wilson n. syn.), P. obscurior (= P. partita Mayr n. syn., = P. incisa evoluta Borgmeier n. syn.) and P. strobeli (= P. rufipilis divexa Forel n. syn., = P. nitidula daguerrei Santschi n. syn., = P. perversa Forel n. syn., = P. perversa richteri Forel n. syn., = P. strobeli misera Santschi n. syn.). Finally, six new species are described: P. abakytan n. sp., P. abaticanga n. sp., P. cangussu n. sp., P. curupira n. sp., P. mapinguari n. sp., and P. obapara n. sp

Morphological differentiation between species of Myrmelachista Roger (Formicidae: Formicinae) in Atlantic Forest areas of the Alto Tietê (São Paulo)

Myrmelachista is an exclusively Neotropical ant genus. The ants from this genus nest and forage in live or dead trees, but data on its life cycle are relatively scarce. The taxonomy of this genus is considerably complex. The morphological characters of taxonomic importance are not well defined, and combining characteristics from the largest possible number of castes is thus essential. The goal of the present study was to present the results of multidimensional morphological analyses conducted based on morphometric measurements of workers and alates to help with the identification of Myrmelachista species. For that purpose, we gathered data from 277 specimens (workers, males and gynes) from eight species cohabiting Atlantic Forest areas. Eighteen morphometric variables were measured on workers and 20 on reproductive ants. Measurements related to eye size and mandible width were the variables more strongly associated with the two morphological clusters obtained based on the morphology of workers. However, the morphospace described by workers cannot be used to delimit the species of Myrmelachista. Mandible width, petiole height and eye size (eye length and ocelli width) were the most informative variables associated with the four clusters of morphology that clearly delimit males of M. arthuri, M. ruszkii/sp.7, and in part, M. catharinae. Finally, petiole length and head length were the best descriptors of the six morphological clusters recognized for gynes. M. catharinae, M. sp.7, M. nodigera and M. gallicola were clearly delimited in the gyne morphological space. M. ruszkii showed high phenotypic variability, and this species was classified in two morphological clusters based on gyne specimens. Species identification employing multiple gyne morphological traits exhibited the best results. Our results show that morphospace analysis can be useful for delimitation of Myrmelachista species

The Ant Genus Sphinctomyrmex

The ant genus Sphinctomyrmex has been represented in the Neotropical Region until now by a single species, S. stali, known only from sparse localities in southeastern Brazil. Two new neotropical species are herein described, S. marcoyi sp. n. and S. schoerederi sp. n. from workers collected in the Brazilian Amazon and Atlantic Forest, respectively. New records for Sphinctomyrmex stali are presented, and the species is redescribed together with discussions on its high morphological variation and the identity of its type specimen. A key for the neotropical Sphinctomyrmex workers, images of all species presently known, and a distribution map are supplied

As formigas poneromorfas do Brasil

Resultado do projeto "Rede Multidisciplinar de Estudos sobre Formigas Poneromorfas do Brasil", o livro apresenta um conjunto de estudos originais ou revisões bibliográficas que focalizam o comportamento, desenvolvimento e contribuições das formigas poneromorfas para o ecossistema