Departamento de Sistemática e Ecologia

With the increasing devastation of the tropical rain forest, there is a critical need to understand how animal forest communities are structured and how habitat degradation will affect these communities. We conducted a field survey to investigate the microhabitat preferences of two co-occurring species of scorpions (Tityus pusillus and Ananteris mauryi) in a fragment of Atlantic rainforest, as well as their abundance and their ecological niche, during both the dry and rainy seasons. Behavioural aspects related to the use of the environment and the proportions of juveniles and adults are also described. The occurrence of intra-and interspecific coexistence was assessed by active search. In addition, pitfall catches were used to assess the structure of the population in the dry and rainy seasons. The differential patterns of spatial distribution in the litter layers provided evidence of partial niche partitioning between the two coexisting scorpion species depending on age and climatic conditions. Abundance, foraging behaviour and age structure (juveniles and adults) were seasonally influenced. We conclude that the diverse and subtle behaviours involved in interaction and habitat use may facilitate species coexistence. Resource partitioning and refuge sharing on a temporal and/or spatial scale, as well as predation pressure, may drive the dynamics and spatial distribution of scorpion species in the rain forest environment.

The concept of areas of endemism (AoEs) has rarely been discussed in the literature, even though the use of methods to ascertain them has recently increased. We introduce a grid-based protocol for delimiting AoEs using alternative criteria for the recognition of AoEs that are empirically tested with harvestmen species distributions in the Atlantic Rain Forest. Our data, comprising 778 records of 123 species, were analysed using parsimony analysis of endemicity and endemicity analysis on four different grids (two cell sizes and two cell placements). Additionally, we employed six qualitative combined criteria for the delim-itation of AoEs and applied them to the results of the numerical analyses in a new protocol to objectively delimit AoEs. Twelve AoEs (the most detailed delimitation of the Atlantic Rain Forest so far) were delimited, partially corroborating the main divisions previously established in the literature. The results obtained with the grid-based methods were contradictory and were pla-gued by artefacts, probably due to the existence of different endemism patterns in one cell or to a biogeographical barrier set obliquely to latitudinal and longitudinal axes, for example. Consequently, the congruence patterns found by them should not be considered alone; qualitative characteristics of species and clade distributions and abiotic factors should be evaluated together. Mountain slopes are the main regions of endemism, and large river valleys are the main divisions. Refuges, marine transgressions and tectonic activity seem to have played an important role in the evolution of the Atlantic Rain Forest.

The increasing devastation of tropical forests makes it critical to understand the structure of their animal communities. Based on this assumption, we conducted a field study to investigate the microhabitat use of the scorpion community in a montane marsh ('Brejo' formation). During three months, samples were actively collected during the night with the help of a UV flashlight. The distinct spatial distributions within a habitat indicated distinct niche partitioning among coexisting species of scorpions. Based on these results, we conclude that individual differences in the use of the environment can facilitate coexistence among species. Competition for shelters at different spatial scales and predation pressure can highly affect the dynamics and distribution of scorpion species in a tropical forest.

The increasing devastation of tropical forests makes it critical to understand the structure of their animal communities. Based on this assumption, we conducted a field study to investigate the microhabitat use of the scorpion community in a montane marsh ('Brejo' formation). During three months, samples were actively collected during the night with the help of a UV flashlight. The distinct spatial dis-tributions within a habitat indicated distinct niche partitioning among coexisting species of scorpions. Based on these results, we con-clude that individual differences in the use of the environment can facilitate coexistence among species. Competition for shelters at dif-ferent spatial scales and predation pressure can highly affect the dynamics and distribution of scorpion species in a tropical forest. Uso de microhábitats por las especies de escorpiones (Arachnida: Scorpiones) en la pluviselva atlántica montana, Brasil Resumen:

Uroderma magnirostrum Davis, 1968 is reported from four new localities in southeastern Brazil, significantly extending its geographical distribution south and westward. A total of 12 adult specimens collected in areas of Caatinga and Atlantic Forest in the states of Minas Gerais, Espírito Santo, and Rio de Janeiro, including specimens from the new localities and museum specimens were examined. Females from southeastern Brazil were larger than males in all external measurements analyzed, but after univariate statistical analyses using corrected p values for multiple tests no significant sexual dimorphism was detected. Mean values obtained from this sample fall within the known range documented for the species in both external and cranial measurements, and are similar to those found in specimens from north and northeastern Brazil. The habitats of the new localities of U. magnirostrum in southeastern Brazil ranged from pristine and secondary forests to a small urban park. Uroderma magnirostrum is apparently a rare species in southeast Brazil, which corroborates most previous reports of populations of this bat at other localities.

Pygoderma bilabiatum is a medium-sized short-faced stenodermatine bat (Chiroptera: Phyllostomidae) with prominent doughnut-shaped glandular tissue masses surrounding the eyes, among other distinctive characters. In this paper, we describe gross external morphology of newly discovered swellings of Pygoderma, probably enclosing glandular tissue found in the dorsal forelimbs of certain male individuals and discuss intra-specific variation in their development. All male individuals observed with large forelimb swellings also had largely developed periorbital and submandibular glands thus suggesting that all male skin glands/swellings in this species develop more or less concordantly. The episodic chronological distribution of male Pygoderma specimens with developed forelimb swellings suggests a relationship with reproductive cycles.

Phyllops falcatus (Gray, 1839), a medium-sized short-faced bat, is a phyllostomid commonly called the Cuban white-shouldered bat or the Cuban bat. This single extant species of Phyllops is characterized by distinct patches of white hair on each shoulder and just behind the posterior insertion of the ears, and a transparent dactylopatagium minus. P. falcatus is a foliage-roosting bat distributed across the Cuban Archipelago, Cayman Islands, and the Island of Hispaniola where it prefers forested habitats at low elevations (below 680 m). This species is rare in zoological collections and has previously been listed in the lower risk-near threatened category.

We report a list of species of bats occurring in Belo Horizonte, the capital of Minas Gerais state, southeastern Brazil. We recorded 16 species belonging to three families,Vespertilionidae, Molossidae, and Phyllostomidae. Artibeus lituratus was by far the most abundant species, representing 70% of the captures. Remnants of native vegetation in urban parks as well as the urban arborization which frequently includes chiropterocoric or chiropterophilous species, as well as the illumination that attracts a great range of insects and houses and buildings also attract and maintain a quite rich assemblage of bats living in Belo Horizonte. Roost search seems to be the most effective method to find mollosids that would not be recorded by mist netting.

Demonstrating their flexibility, some species of bats have adapted themselves to artificial roosts. The availability of refuges and the bats' ways of using them may influence the size of their colonies, dispersal of individuals, foraging strategy, and social behavior. In this paper, we report a peculiar roost occupation by bats in and near the Parque Estudual do Rio Doce, Brazil, and provide preliminary information concerning the diet of these bats.