Maria Cristina dos Santos-Costa

Amphibians from southeastern state of Pará: Carajás Region, northern Brazil

The region of Carajas in the southeast of the state of Para, Brazil, harbors five reserves, with various managing categories, distributed throughout five municipalities. A list of amphibians known to occur in this region was compiled using information on the specimens deposited in the herpetological collection of the Goeldi Museum, collected during the past four decades (1969 - 2010). According to the available metadata, the species were tabulated in three environments: ombrophylous forest (rainforest), metalophic savanna (MS) and anthropic areas (AA - secondary forest - disturbed areas), resulting in 13 families and 71 species (66 anurans and 5 Gymnophiona). Ombrophylous forest has 50 species, anthropic areas has 49 species, while metalophic savanna has 38 species of anuran.

MORPHOLOGY, REPRODUCTIVE BIOLOGY AND DIET OF DENDROPHIDION DENDROPHIS (SCHLEGEL, 1837) (SERPENTES, COLUBRIDAE) IN BRAZILIAN AMAZON

Abstract Reproductive (sexual dimorphism, reproductive maturity, reproductive cycle, recruitment and fecundity), feeding biology (diet composition and frequency of food items) and morphology data (body size and tail breakage) of Dendrophidion dendrophis are presented, based on the analysis of 95 specimens (61 males and 34 females) from different regions of Brazilian Amazon. There were no significant differences in the snout-vent length and tail length between males and females. Males reach reproductive maturity with a smaller snout-vent length than females, which become sexually mature when they reach approximately three times the size of the newborns. A positive, yet only slightly significant, relationship was observed between the number of vitellogenic follicles and eggs and the snout-vent length of the females. Reproductive activity occurs throughout the year, suggesting aseasonal breeding for the species. The high incidence of broken tail or visible rupture points in mature and immature males and females corroborates the hypothesis of tail breakage as a defense mechanism in this species. All food items found were frogs of the subfamily Leptodactylinae (family Leptodactylidae), most often from the genus Adenomera, followed by Physalaemus, suggesting that D. dendrophis is primarily terrestrial and anurophagous.

Feeding ecology of Liophis reginae semilineatus (Serpentes: Colubridae: Xenodontinae) in eastern Amazon, Brazil

We studied the diet of Liophis reginae semilineatus (Wagler, 1824) from eastern Amazon, Brazil, based on the analysis of 182 preserved specimens. Thirty-six individuals had prey in their stomachs; 34 (95%) contained exclusively anurans and 2 (5%) contained both anurans and lizards. The most common prey items were small Leptodactylus sp. (33.3%), followed by Physalaemus ephippifer (Steindachner, 1864) (10.3%). Prey ingested head-first (78%; n = 25) were significantly larger than prey ingested tail-first (22%; n = 7). Females of L. reginae semilineatus have longer and wider heads than conspecific males with the same body length, which correspond to sexual divergences in the diet (size of the prey). No correlation was found between snake head length vs. prey size (SVL, width and mass). Liophis reginae semilineatus is an anurophagous snake that probably forages actively on the ground.

Reproductive Biology of Tantilla Melanocephala (Linnaeus, 1758) (Serpentes, Colubridae) from Eastern Amazonia, Brazil

Abstract The reproductive biology of Tantilla melanocephala was studied in eastern Amazonia, Pará, Brazil. Males and females attained sexual maturity at approximately twice the length (snout–vent length  =  SVL) of newborn snakes. Mature males had a larger tail length and more subcaudal scales than mature females, whereas females were larger (SVL) and had more ventral scales than males. Total length did not differ between mature males and females. Reproduction was not seasonal. There was no correlation between the number of vitellogenic follicles and oviductal eggs. The number of eggs was positively correlated with the female SVL. The data presented here indicate that the eastern Amazonia population differs from populations in southeastern Brazil in important morphological and reproductive aspects, including the mean number of eggs produced (mean  =  1.53), which was smaller in eastern Amazonian populations.

Serpentes da Bacia Petrolífera de Urucu, Município de Coari, Amazonas, Brasil

Um inventario estruturado de serpentes foi realizado na Base Operacional Geologo Pedro de Moura (BOGPM), localizada na Bacia Petrolifera de Urucu, Municipio de Coari, Amazonas, nos anos de 2003, 2004 e 2007. Nas quatro expedicoes realizadas (51 dias de coleta) foram registradas 47 especies de serpentes, pertencentes a sete familias e 33 generos. Foram utilizados quatro metodos complementares de amostragem de serpentes: armadilha de interceptacao e queda, encontros ocasionais, procura limitada por tempo a pe e procura limitada por tempo de carro. Das 47 especies coletadas, Liophis reginae (n= 14), Philodryas viridissima (n= 9), Philodryas boulengeri (n= 7) e Oxybelis fulgidus (n= 7) foram as mais abundantes em toda regiao. O maior numero de especies e especimes foi registrado pela procura limitada por tempo de carro (52,8%). Estudos anteriores indicam que as localidades ao sul do Rio Amazonas (como regiao Leste do Para, Usina Hidreletrica de Tucurui, Estado do Para, e de Samuel, Estado de Rondonia) apresentam maior riqueza quando comparadas as regioes ao norte do Amazonas (como Municipio de Manaus, Reserva do INPA-WWF e Usina Hidreletrica de Balbina, Estado do Amazonas). Desta forma, e possivel inferir que o levantamento das serpentes da regiao de Urucu ainda nao esteja completo, sendo necessario um maior esforco de coleta para que novos registros sejam adicionados para a area.

Anuran Beta Diversity in a Mosaic Anthropogenic Landscape in Transitional Amazon

Abstract Can the loss of forest habitat cause changes in local communities? The results of our study of anuran assemblages in the southern Amazon indicate that the conversion of forest into open environments results in the substitution of species and the reduction of beta diversity. The increasing loss of tropical forests to agricultural development, especially in the Amazon, has resulted in the extensive modification of the natural landscape, transforming once-continuous forests into a mosaic of modified habitats. Our data indicate that this process resulted in the substitution of forest species by generalists, which are more typical of open environments. Also, this process has a homogenizing effect, making different areas more similar to one another, resulting in a decrease in beta diversity. This substitution–homogenization process may become increasingly common through the ongoing advance of agricultural frontiers, resulting in the local extinction of an important component of the biodiversity of tropical forests.

Effects of oil palm plantations on anuran diversity in the eastern Amazon.

The extent of land use for oil palm plantations has grown considerably in the tropics due to climate, appropriate soil conditions for cultivation and its profitability. However, oil palm plantations may endanger biodiversity through reduction and fragmentation of forest areas. Herein we analyzed the effects on anuran species richness, composition and total abundance in oil palm plantations and surrounding forests in eastern Amazon. We installed seven plots in oil palm plantations and seven plots in surrounding forests, which we surveyed for the presence of anurans through active visual and acoustic surveys during periods of high and low rainfall levels. Anuran assemblages found in forests and oil palm plantations differed in species richness and composition, with a loss of 54% of species in oil palm plantations. No difference was observed in total abundance of anurans between both environments. While conversion of forests to oil palm plantations may result in less negative impacts on anuran diversity than other types of monocultures, such loss is nevertheless high, making the maintenance of relatively greater forested areas around oil palm plantations necessary in order to conserve anuran diversity.

Anurans of the Urucu Petrol Basin, municipality of Coari, State of Amazonas, northern Brazil

We present the first species amphibian list for municipality of Coari, state of Amazonas, Brazil. The list was drawn up as a result of data obtained from specimens deposited in the Herpetological Collection of the Museu Paraense Emilio Goeldi and inventories conducted in the Urucu Petrol Base, in 2003-2004 and 2007-2009. Sampling methods included pitfall traps with drift fences and time constrained searches. We considered the data collected by other researchers, incidental encounters and records of dead individual on the road. Fifty four species were recorded. Rhinella gr. margaritifera (n= 68), Adenomera gr. marmorata (n= 59), and Osteocephalus leprieurii (n= 20) were the most collected, while ten species were less collected. Compared with other studies in eastern Amazonia, the region of Urucu presented a large number of anurans. Nonetheless, it s not possible to confirm this because the data collected were not standardized among studies. However, further studies by, increasing the sampling effort, could prove this area to be richer in anurans than that observed so far.

Species composition and reproductive modes of anurans from a transitional Amazonian forest, Brazil

The aim of the present study was to describe the species composition and reproductive modes of an anuran community from a transition area between the Amazonia and Cerrado biomes. Data were collected in habitats exhibiting different degrees of anthropogenic degradation. The community (35 species) identified during the present study presented a larger number of reproductive modes when compared with those from Cerrado communities, but smaller than those of other sites in the Amazon. While all nine modes were recorded in the gallery forests of local rivers and streams, anthropogenic habitats (rubber tree orchards and soybean fields) were occupied only by species adapted to environments where humidity is low, typical of the Cerrado. Overall, the anuran fauna of the study area was characterized by species that depend on access to water bodies for their reproduction, with only a few specialized species able to reproduce in dry environments.

Geographical variation in the reproduction and sexual dimorphism of the Boddaert's tropical racer, Mastigodryas boddaerti (Serpentes: Colubridae)

We obtained data on time of sexual maturity, dimorphism, fecundity and on the reproductive cycle of Mastigodryas boddaerti (Sentzen, 1796) through the examination of 321 preserved specimens, of which 221 were collected in the Brazilian Amazon region and 100 in the Cerrado savannas of Central Brazil. The degree of sexual size dimorphism (snout-vent length, SVL) was significantly greater in the specimens from the Cerrado in comparison with those from the Amazon. Females had a significantly larger number of ventral scales, on average, whereas males had more sub-caudal scales. However, there was no intersexual difference in tail length or head width, although the heads of the males were significantly longer, which may reflect dietary differences. Breeding females from the Amazon region contained between one and six eggs (N = 12, mean = 3.0), whereas two females from the Cerrado had four to six eggs (N = 10, mean = 5.0). No relationship was found between the SVL of the Amazonian females and the number of eggs or vitellogenic follicles they contained (Cerrado females were not analyzed here due to small sample size). Males are smaller than their female counterpart when they reach sexual maturity. Even though females from the Amazon reproduce throughout the year, females from the Cerrado breed seasonality.