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Aim Our aim was to investigate how the distance to water (flooding gradients) and riverine barriers (Tapajos and Jamanxim rivers) influence the distributional patterns of amphibian and squamate assemblages in the middle Tapajos River region, south-eastern Amazonia. We also considered the planned hydroelectric dams on both rivers in reviewing the possible impacts of these factors on the amphibian and squamate assemblages. Location Middle Tapajos River system, south-eastern Amazonia. Methods We conducted diurnal and nocturnal surveys combining pitfall traps and active searches along both banks of the Tapajos and Jamanxim rivers. We identified specimens using an integrative morphological, acoustic, ecological and molecular approach and evaluated the influence of riverine barriers and distance to water using uni- and multivariate ordinations, regressions and ANOVA. Results We found changes in species composition for both groups along the flooding gradient and differential riverine barrier effects. The rivers restricted the distribution of 33% of the amphibian species and 8% of the squamates. For amphibians, the main distributional barrier was the Tapajos River, while for squamates both rivers were of similar importance. The assemblages most affected by riverine barriers were non-riparian amphibians and squamates, as well as riparian amphibians associated with small streams. The functional groups most affected were small, diurnal terrestrial amphibians and small–medium, diurnal partly tree-dwelling squamates. Main conclusions The Tapajos River is a distributional boundary for lineages centred in western and eastern Amazonia. The fact that many taxa occur on both banks suggests that the Tapajos is a recent or semi-permeable barrier, while the Jamanxim is an even more recent or weaker barrier. Anthropogenic activities that affect water level, flooding cycles and river flow may influence these natural patterns and cause changes to the equilibrium of the riverine barrier effect. Studies seeking to identify these influences should focus on the most affected functional groups.

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) IBAMA A new genus and species of microteiid lizard is described based on a series of specimens obtained at Parque Nacional do Caparao (20 degrees 28'S, 41 degrees 49'W), southeastern Brazil, along the division line between the States of Minas Gerais and Espirito Santo. The new lizard occurs in isolated high-altitude, open, rocky habitats above the altitudinal lit-nits of the Atlantic forest. It is characterized by the presence of prefrontals, frontoparietals, parietals, interparietal, and occipital scales; ear opening and eyelid distinct; three pairs of genials; absence of collar; lanceolate and mucronate dorsal scales; six regular transverse and longitudinal series of smooth ventrals that are longer than wide, with the lateral ones narrower. Maximum parsimony (MP) and partitioned Bayesian (PBA) phylogenetic analyses based on morphological and molecular characters with all known genera of Gymnophthalminae (except for Scriptosaura) Plus Rhachisaurus recovered this new lizard in a clade having Colobodactylus and Heterodactylus as its closest relatives. Both analyses recovered the monophyly of Gymnophthalminae and Gymnophthalmini. The monophyly of the Heterodactylini received moderate support in MP analyses but was not recovered in PBA. To eliminate classification controversy between these results, the present concept of Heterodactylini is restricted to accommodate the new genus, Colobodactylus and Heterodactylus, and a new tribe Iphisiini is proposed to allocate Alexandresaurus, Iphisa, Colobosaura, Acratosaura, and Stenolepis. Current phylogenetic knowledge of Gymnophthalminae suggests that fossoriality and increase of body elongation arose as adaptive responses to avoid extreme surface temperatures, either cold or hot, depending on circumstances. Amer Museum Nat Hist, Div Vertebrate Zool Herpetol, New York, NY 10024 USA Univ Sao Paulo, Inst Biociencias, Dept Zool, BR-05422970 Sao Paulo, Brazil Univ Fed Sao Paulo, Dept Ciencias Biol, Diadema, SP, Brazil Univ Fed Sao Paulo, Dept Ciencias Biol, Diadema, SP, Brazil IBAMA: 094/2004 IBAMA: 185/2005 IBAMA: 238/2006 Web of Science

Two new species of Bachia of the bresslaui group are described from the central Brazilian Cerrados, state of Tocantins. The two species are most similar to Bachia bresslaui and Bachia cacerensis from which they differ in limb morphology and head scalation. In both, the snout is more prominent than that of previously known species, suggesting more pronounced adaptations to fossoriality. One of the new species has stiliform forelimbs and four clawed short toes in the hind limb, an opposite pattern to the condition observed in the genus where limb reduction is more pronounced in hind limbs. The two new species were obtained in relictual sandy soil areas covered by semidecidual or open dry forest vegetation. Considering the relictual condition of these sandy areas, the possible endemism to those areas, and the high level of disturbance of the Cerrados, we strongly suggest that these areas should be the target of special conservation efforts.

A new genus and species of microteiid lizard is described from a series of specimens obtained in the leaf litter at Una (15u109S, 39u039W) in the Atlantic forest of southern Bahia, Brazil. It is characterized by the presence of prefrontals, frontoparietals, parietals, and interparietal; parietals longer than wide; distinct ear openings and eyelids; two pairs of genials, absence of collar and occipital scales; dorsal scales anteriorly smooth and becoming gradually lanceolate and mucronate posterior to the forelimb; and four regular transverse series of smooth ventrals that are longer than wide, identical in size. A phylogenetic analysis based on external morphology, osteology, and molecular data confirms this new lizard as a member of the Heterodactylini radiation of Gymnophthalminae. The topology recovered by maximum parsimony (MP) analyses reveals that its closest relatives are the sister taxa Colobosaura modesta and Iphisa elegans (BS 5, 50%

Among a series of eight specimens of Anolis phyllorhinus obtained in the northern part of the state of Mato Grosso, Brazil, one was determined to be the first female known for the species and the first so far reported for proboscid anoles. The female lacks the characteristic male proboscis and, excepting a few consistent differences, is morphologically similar to females of Anolis punctatus, a species closely related and broadly sympatric with A. phyllorhinus. Males and females of the new series are described and new data on their ecology and behavior presented. The new data are consistent with the hypotheses that the male proboscis probably evolved as a sexual signal and that visual signals for intra and interspecific recognition are redundant in anoles.Em uma série de 8 exemplares de Anolis phyllorhinus coletados em Aripuanã, no norte do estado de Mato Grosso encontra-se a primeira fêmea da espécie, que também vem a ser a primeira fêmea conhecida para os anolis dotados de apêndice nasal. A fêmea não apresenta a probóscide característica dos machos e, exceto por pequenas diferenças, embora consistentes, é morfologicamente muito semelhante às fêmeas de Anolis punctatus, espécie relacionada e amplamente simpátrica com Anolis phyllorhinus. Descrevem-se os machos e a fêmea da nova série, acrescidos de informações obtidas no campo sobre sua ecologia e comportamento. Os novos dados, concordam com hipóteses anteriores sugerindo que a probóscide do macho possívelmente evoluiu como um sinal sexual e que os sinais visuais para reconhecimento intra e interespecífico são redundantes no gênero Anolis.