Soil invertebrates in southern Brazilian Araucaria forest - grassland mosaic: differences between disturbed and undisturbed areas

Soil invertebrate distribution in Araucaria forest, grassland and edge habitats was studied in both disturbed and undisturbed areas in southern Brazil. Mean-density and taxa compositions were verified. Invertebrate densities differed between grassland and the other two habitats in the undisturbed area but not across the disturbed one. At the disturbed area taxa differed between the grassland and the other two habitats. The undisturbed area, on the other hand, presented taxa differences only between the grassland and the forest habitats. Acari, Arachnida and Collembola were the most sensitive taxa for detecting differences across habitats in both areas. At the disturbed area, these taxa presented densities lowering from the forest to the grassland. At the undisturbed area the same taxa increased from the forest to the grassland. Coleoptera and Formicidae (Insecta) presented no difference between habitats at the studied taxonomic level.

Molecular phylogenies, chromosomes and dispersion in Brazilian akodontines (Rodentia, Sigmodontinae)

A new molecular phylogeny for akodontine rodents from Brazil was proposed. The phylogenetic tree was enriched with the area of occurrence and with information on the karyotype of the samples. Based on this enriched tree, and with a described methodology, hypotheses were proposed on the karyotype and area of occurrence of the ancestors of each Clade. Thus it was possible to discuss hypotheses on chromosome evolution of the group, and on dispersion events from the "area of original differentiation" of akodontines in the Andes. Chromosome evolution started with high diploid numbers (2n=52) and showed a tendency to reduction (until 2n=14 in more recent clades). Independent side-branches of the tree showed 2n reduction and in one case the 2n increased. At least four dispersion events from the Andes down to South-eastern Brazil were proposed. The results should suggest the direction of new studies on comparative karyology.

Revalidation of Acanthagrion cuyabae (Odonata, Coenagrionidae) and description of the female, with a key to the Brazilian species of the viridescens group

Acanthagrion cuyabae Calvert, 1909 was described based on a male from State of Mato Grosso, Brazil. The female of this species was described based on morphological characters of four individuals collected in copula from State of Mato Grosso do Sul, and three other specimens of same locality. Acanthagrion cuyabae is here revalidated based on morphological characters of the female. Illustrated keys to the groups of Acanthagrion Selys, 1876 and species of the viridescens group occurring in Brazil are provided.

Natural history of the lizard Enyalius iheringii (Squamata, Leiosauridae) in southern Brazilian Atlantic forest

Studies on the natural history of the lizard Enyalius iheringii Boulenger, 1885, as well as other tropical lizards, are rare. In this study, some aspects of the natural history of this endemic species from the Atlantic forest are reported in areas of Vale do Itajaí, state of Santa Catarina, Brazil. Twenty individuals were found, of which 18 were collected. Most of them were found over the vegetation (n=17) and on the ground (n=3). The main defensive strategy displayed was camouflage (n=16). Jumping (n=1), jumping and running (n=1) and running (n=2) were also observed in some individuals. When handled, lizards exhibited mouth wide open, hissing, and occasionally biting, as well as color change in males. Regarding its diet, the numerically most important prey was beetles (Coleoptera), followed by Lepidoptera larvae. Beetles, lepidopteran larvae and spiders were the most frequent food items. Males and females did not differ in size. Three sexually mature females (100-113 mm SVL) were found in December and January.

New and significant bird records from Rio Grande do Sul, with comments on biogeography and conservation of the southern Brazilian avifauna

I report on the occurrence of 16 species of birds in Rio Grande do Sul, southern Brazil, of which seven are new for the state - Accipiter superciliosus (Linnaeus, 1766), Brotogeris tirica (Gmelin, 1788), Hemitriccus margaritaceiventer (d'Orbigny & Lafresnaye, 1837), Phyllomyias griseocapilla Sclater, 1862, Saltator coerulescens Vieillot, 1817, Orthogonys chloricterus (Vieillot, 1819), and Sporophila lineola (Linnaeus, 1758) - and seven were previously known from unsubstantiated or poorly documented records - Ixobrychus exilis (Gmelin, 1789), Brotogeris chiriri (Vieillot, 1818), Coccyzus euleri Cabanis, 1873, Pulsatrix koeniswaldiana (Bertoni & Bertoni, 1901), Psilorhamphus guttatus (Ménétriès, 1835), Serpophaga griseicapilla Straneck, 2007, and Hemithraupis ruficapilla (Vieillot, 1818). Descriptive and natural history notes are presented for some of these species. The records of B. tirica, P. guttatus, P. griseocapilla, Myiozetetes similis (Spix, 1825), O. chloricterus, H. ruficapilla, and S. lineola represent significant southward range extensions of up to 300 km. Also, a new confirmed record of Myiarchus ferox (Statius Muller, 1776) is divulged. Finally, I argue that the Atlantic forests of north-eastern Rio Grande do Sul should be included in the Serra do Mar area of endemism (sensu SILVA et al., 2004) because of the presence of Orthogonys chloricterus, and comment on the possible range expansion of Myiozetetes similis, Sporophila lineola and other primarily tropical species in southern Brazil.

Taxonomic revision of doubtful Brazilian freshwater shrimp species of genus Macrobrachium (Decapoda, Palaemonidae)

The freshwater prawns of the genus Macrobrachium Spence Bate, 1868 are widely distributed in rivers of tropical and subtropical regions and represent an interesting group with controversial taxonomy. The morphological characters traditionally used to separate species have shown a high intraspecific variation. Doubts about the status of M. birai Lobão, Melo & Fernandes, 1986, M. holthuisi Genofre & Lobão, 1978 and M. petronioi Melo, Lobão & Fernandes, 1986 have been arisen due to the high resemblance of the former two species with M. olfersi (Wiegmann, 1836), and the latter one with M. potiuna (Müller, 1880). Therefore, we performed a detailed morphological analysis of these species, including new characters not usually used in the species recognition. The present results here with molecular data lead us to conclude that M. birai and M. holthuisi are junior synonyms of M. olfersi, and M. petronioi is a junior synonym of M. potiuna. Considering these synonymies, 17 valid species are now reported for the Brazilian territory.