The western region of Brazil consists of a mosaic of vegetation types, including savanna steppe (Cerrado), Chaco arborous and gramineous, xeromorphic and mesoxeromorphic forests associated with the Bolivian and Paraguayan chacos, tropical seasonal deciduous and semi-deciduous forests, rocky fields, and marshes in flooded lowlands. The Pantanal is rich in vegetation types, which largely a consequence of the variety of geomorphologic and topographical characteristics. Among these, the cordilheiras, capões de mata, and paratudais are plant formations; the first two are semideciduous forest patches and the last one is a monotypic arboreal formation of Tabebuia aurea (Manso).
The assessment of the structure of the diversity of ants in Mato Grosso do Sul, Brazil, is an important step in understanding the distributional patterns at a regional scale. This study has great biogeographic importance, because the region is a big transitional area between Cerrado biome and Brazilian Atlantic Forest, and between the Pantanal and the Amazon forest, one of the most species-rich floodplains in the world.
The Mato Grosso do Sul (MS) specimen records on Antweb are drawn from a series of field collections conducted between 2005 and 2011. This list of ant species of MS was designed based in two projects. The first is a research project entitled “Biodiversity of Hymenoptera of Serra da Bodoquena National Park,” which consists of an inventory of ants, bees, stinging wasps (Aculeata) and micro-parasitic wasps; the second is a teaching project, where students from Universidade Federal da Grande Dourados (UFGD) visit environmental conservation units in the Pantanal region as part of a course on field Entomology (PPGECB/FCBA/UFGD). In these projects the following protocols are used for sampling: leaf-litter sampling with the Winkler apparatus; sardine baits in the soil and vegetation; pit-fall traps in the soil; underground traps; Malaise traps; yellow pans; entomological nets; and hand collecting. Specimens are deposited in the entomological collection of the Museum of Biodiversity UFGD/FCBA in Dourados, Mato Grosso do Sul.
To date, 293 species in 65 genera and 13 subfamilies have been found in Mato Grosso do Sul. Partial results of the litter fauna were published in Silvestre, Demetrio & Delabie (Psyche, 2012).
We recorded the first observations of Stegomyrmex olindae Feitosa, Brandão & Diniz, 2008 in Maciço do Urucum, the genus Kalathomyrmex Klingenberg & Brandão, 2009, and Cryptomyrmex Fernandez, 2004, in the Central West Brazilian region. Three new species were found in deciduous forest: Asphinctanilloides sp. new, Stigmatomma sp. new, and Probolomyrmex sp. new. The species yet to be described were deposited in the collection of Dr. Carlos R. F. Brandão (MZ/USP/SP) and in the collection of Dr. Jacques H. C. Delabie (CEPLAC/UESC/BA).
Our results suggest that the studied sites exhibit different arrangements of ant fauna with abundant species being replaced across sampling units, resulting in high beta diversity. The conservation status and potential connections between forest sites affects the species persistence and colonization of each site.
In central-western Brazil, the expansion of agriculture and intensive cattle farming has led to a dramatic loss of forests. It is thus likely that ant diversity in this region has been affected before it can be thoroughly evaluated.
This study was carried out under a collection permit from IBAMA (number 10674-11/09/2007). Support was provided by the research agencies CNPq and FUNDECT.