Trophic ecology and foraging behavior of Tropidurus hispidus and Tropidurus semitaeniatus (Squamata, Tropiduridae) in a caatinga area of northeastern Brazil

This study aimed to analyze the seasonal variation in diet composition and foraging behavior of Tropidurus hispidus (Spix, 1825) and T. semitaeniatus (Spix, 1825), as well as measurement of the foraging intensity (number of moves, time spent stationary, distance traveled and number of attacks on prey items) in a caatinga patch on the state of Rio Grande do Norte, Brazil. Hymenoptera/Formicidae and Isoptera predominated in the diet of both species during the dry season. Opportunistic predation on lepidopteran larvae, coleopteran larvae and adults, and orthopteran nymphs and adults occurred in the wet season; however, hymenopterans/Formicidae were the most important prey items. The number of food items was similar between lizard species in both seasons; however the overlap for number of prey was smaller in the wet season. Preys ingested by T. hispidus during the wet season were also larger than those consumed by T. semitaeniatus. Seasonal comparisons of foraging intensity between the two species differed, mainly in the wet season, when T. hispidus exhibited less movement and fewer attacks on prey, and more time spent stationary if compared to T. semitaeniatus. Although both lizards are sit-and-wait foragers, T. semitaeniatus is more active than T. hispidus. The diet and foraging behavior of T. hispidus and T. semitaeniatus overlap under limiting conditions during the dry season, and are segregative factors that may contribute to the coexistence of these species in the wet season.

Ecologia comportamental de tropidurus Hispidus e Tropidurus Semitaeniatus (Squamata, Tropiduridae) em Simpatria, em área de caatinga do nordeste do Brasil.

This study evaluated the spatial, time and alimentary niches of Tropidurus hispidus and Tropidurus semitaeniatus in sympatry in a caatinga of Rio Grande do Norte, Brazil, as well as their foraging and termoregulatory behaviors, the activity body temperature and their reproductive and fat body cycles. Monthly excursions, from October 2006 to May 2008, were conducted at the Ecological Station of the Seridó (ESEC Seridó), Serra Negra do Norte municipality, using specific methodology for investigation of the aforementioned objectives. The two species presented similarities in space niche use, mainly in rocky habitat, however they differed in vertical microhabitat use with T. hispidus using a larger vertical microhabitat range. In the dry season the time of activity of both species was bimodal. In the wet season T. semitaeniatus showed a unimodal activity period, while T. hispidus maintained an bimodal activity period. In terms of importance in the diet, to both species, Hymenoptera/Formicidae and Isoptera predominated during the dry season. In the wet season, although Hymenoptera/Formicidae had larger importance among the prey items, lizards opportunistically predated on Lepidoptera larvae, Coleoptera larvae/adults and Orthoptera nymphs/adults. The foraging intensity revealed differences between the species, mainly in the wet season, when T. semitaeniatus was more active than T. hispidus. The mean activity body temperature of T. semitaeniatus was significantly higher than that of T. hispidus. The thermoregulatory behavior showed that during the dry season T. hispidus and T. semitaeniatus spent more time in shade or under filtered sun. In the wet season, T. hispidus did not show differences in the amount of time spent among the light exposure locations, however T. semitaeniatus spent most of their time exposed to direct sun or filtered sun. The reproductive cicle of T. hispidus and T. semitaeniatus occurred from the middle of the dry season to the beginning of the wet season. In both species, female reproductive activity was influenced by precipitation, whereas males exhibited spermatozoa in their testes throughout the year, and their reproductive activity was not related with any of the climatic variables analysed. In the two species, the fat storage varied inversely with reproductive activity, and there was no difference in fat body mass between females and males. We concluded that the segregation between T. hispidus and T. semitaeniatus in this caatinga area occurs in vertical space use, in the largest vagility of T. hispidus in microhabitat use and larger range size of their alimentary xviii items. Additionally, significant seasonal differences in relation to the activity period, body temperature, and foraging and termoregulatory behaviors between these two Tropidurus species facilitate their coexistence.

Expressão de zif268 no cérebro do lagarto Tropidurus Hispidus após exploração de um ambiente enriquecido.

In the present work, we investigated behavioral changes associated with the increase in Zif268 protein expression within telencephalic areas of the tropical lizard Tropidurus hispidus that correspond to the mammalian hippocampus (HC). We used 13 male individuals of this species, collected at the Federal Agrotechnical School of Rio Grande do Norte, under SISBIO license number 19561-1. Four animals had their brains removed and were submitted to a Western blot with antibodies for the Zif268 protein. The remaining animals were separated in two different groups: a control group (n=4) and an exploration group (n=5). Animals from the exploration group were exposed to an enriched environment with many sensory cues novel to them. Control group animals stayed in the environment they were already habituated to. After 90 min from the onset of exposure to the new environment, animals from both groups were submitted to intracardiac perfusion with fixative, and the brains were removed, cryoprotected and frozen. After that, brains were sectioned at 20 μm and the sections were subjected to immunohistochemistry for the Zif268 protein. We verified that the Zif268 protein is likely conserved in the brain of T. hispidus, which showed antigenicity for the antibody anti-Zif268 made in mammals. In animals from the exploration group, we detected an increase of the Zif268 protein in the Septum, Striatum, Dorsoventricular Area and in cortical areas corresponding to the HC. This increase was proportional to the amount of environmental exploration, with maximum positive correlation in the hippocampal subareas Medial Cortex (R = 0.94 and p = 0.004) and Dorsomedial Cortex (R = 0.92 and p = 0.006). The data corroborate the notion that the reptilian hippocampus, as well as the mammalian HC, plays an important role in spatial exploration.

Pterygosomatidae and Trombiculidae mites infesting Tropidurus hispidus (Spix, 1825) (Tropiduridae) lizards in northeastern Brazil

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Tropidurus hispidus Spix 1825 (Sauria, Tropiduridae): a new host for Oswaldofilaria petersi Bain & Sulahian 1974 (Nematoda, Onchocercidae)

No presente trabalho descreve-se a ocorrência de Oswaldofilaria petersi Bain & Sulahian 1974 (Nematoda, Onchocercidae) em Tropidurus hispidus Spix 1825 (Sauria, Tropiduridae). Um macho e uma fêmea de O. petersi foram coletados no músculo ileofibularis direito desse lagarto. Este é o primeiro relato deste hospedeiro para Oswaldofilaria spp. e também a descrição de um novo hospedeiro para O. petersi.

Gastrointestinal nematodes of the lizard Tropidurus hispidus (Squamata: Tropiduridae) from a semi-arid region of north-eastern Brazil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Spatial-temporal variation of parasites in Cnemidophorus ocellifer (Teiidae) and Tropidurus hispidus and Tropidurus semitaeniatus (Tropiduridae) from Caatinga areas in northeastern Brazil

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Dieta e compotamento de forrageio de duas espécies de Tropidurus (Squamata,Tropiduridae) em uma área de Caatinga do Nordeste do Brasil

Tropidurus semitaeniatus and Tropidurus hispidus are lizard species that are widely distributed in Brazil. The former is endemic to the Caatingas, where they live in syntopy with the latter, which is distributed in other ecosystems and biomes. In this work, diet was evaluated including seasonal variations as well as foraging behavior, to determine the importance of these factors in the structure of these populations and the coexistence of these species in syntopy. No significant difference was found in diet composition between the two species, although T. hispidus feed on larger preys than do T. semitaeniatus; this fact, along with the different foraging behavior in the rainy season, are ecological factors that contribute to the syntopic coexistence of these species in the Caatinga area studied

Diversidade de espécies e ecologia da comunidade de lagartos de um fragmento de Mata Atlântica no nordeste do Brasil

Neste estudo foram investigadas a diversidade, a composição, e as diferenças no uso do espaço (hábitat e microhábitat) e do alimento em uma comunidade de lagartos habitantes da serapilheira de um fragmento de Mata Atlântica, do Estado de Alagoas, Brasil. Para a observação e/ou coleta dos espécimes, foram utilizados os métodos de busca ativa e armadilhas de queda (pit-fall traps) sem cerca-guia. Para análises de diversidade e da existência de diferenças de diversidade entre os hábitats e microhábitats, utilizou-se o índice de Shannon. A largura dos nichos espacial (hábitat e microhábitat) e alimentar foi avaliada, utilizando-se o índice de diversidade de Simpson. A similaridade entre as áreas foi averiguada utilizando-se o índice de Jaccard. Para avaliar o grau de sobreposição quanto ao uso do espaço (hábitats e microhábitats) e do alimento pelas espécies, foi utilizada uma versão da equação de MarcArthur & Levis. Foram obtidas vinte e três espécies de lagartos, pertencentes a nove famílias; destas, dezenove foram obtidas no interior da mata e nove na borda. Para o interior da mata as espécies mais abundantes foram Kentropyx calcarata, Dryadosaura nordestina, Enyalius catenatus e Gymnodactylus darwinii. Na borda da mata as espécies mais abundantes foram Tropidurus hispidus, T. semitaeniatus, Ophiodes striatus e Ameiva ameiva. Quanto à utilização dos recursos, os resultados mostraram que espécies filogeneticamente próximas nem sempre utilizam de maneira semelhante os recursos disponíveis. A dieta em geral foi composta por artrópodes. Tropidurus hispidus e T. semitaeniatus se mostraram especialistas no consumo de Himenoptera (Formicidae), que estiverem presentes em 100% dos seus estômagos. Ophiodes striatus teve como principal alimento caramujos (Gastropoda) e aranhas com 60% cada; sendo Gastropoda mais abundante para esta espécie

Lung infection rates in two sympatric Tropiduridae lizard species by pentastomids and nematodes in northeastern Brazil

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Nematodes of Lizards (Reptilia: Squamata) from Caatinga Biome, Northeastern Brazil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Ecologia trófica de uma comunidade de lagartos da caatinga

The trophic ecology studies issues related to the diet of individuals within a community .The relation between the body size of the predator and the prey size, individual specialization and niche breadth are some of the issues that can be discussed by it .I collected the lizards using pitfall trap, glue and active collecting traps in a fragment of Caatinga. The most common species in this community were Tropidurus hispidus, T. semitaeniatus and Cnemidophorus ocellifer. The visits to the farm also relied on collecting invertebrates at each season to understand how the nutritional resources of lizards were presented in each one of them. I tried to answer some questions : 1) If there was a positive relation between body size of the predator and the size of prey of the community ; 2) If in different seasons the relation of body size of the predator and the maximum and/or minimum size of the prey would be positive ; 3) If species with different foraging strategies have positive relation on the size of the predatorprey relation; 4) If the seasonality would influence on the individual expertise of lizards community and more common species; 5) If the breadth of the niche would be influenced by seasonality ; 6) If more individuals with different morphology between them would present less similar diet. I found that there was indeed a positive relationship between size of prey and predator, but nonexistent related to the minimum size of prey; Among the seasons relative size of predators and prey was different for the maximum and minimum size, but was positively related only to the size of the maximum prey. And comparisons between different foraging strategies had the maximum and minimum line inclination greater than zero and different from each other; individual specialization was not influenced by seasonality and the niche breadth was wider in the dry season only to T. semitaeniatus. At last I didn't find a significant negative relationship between morphological dissimilarity and similarity of diet.

Comparative cytogenetic studies of eleven species of the Tropidurus torquatus group (Sauria, Tropiduridae), with banding patterns

The chromosomes of 173 specimens representing eleven species of the Tropidurus torquatus group, from 33 localities in Brazil, were analysed after Giemsa staining, C-banding, NORs, and replication banding techniques. A karyotype with 2n = 36, including 12 macrochromosomes and 24 microchromosomes (12 M + 24 m), and sex determination of the XY:XX type were found in Tropidurus cocorobensis, T. erythrocephalus, T. etheridgei, T. hispidus, T. hygomi, T. montanus, T. mucujensis, T. oreadicus, and T. torquatus. The two other species, T. itambere and T. psammonastes, presented 2n = 36 (12 M + 23 m) karyotype only in females while males had 2n = 35 (12 M + 23 m), due to the sex determination of the X(1)X(2)Y:X(1)X(1)X(2)X(2) type. Other interspecific differences as well as some intraspecific variation regarding the NORs and C-banding patterns have been observed, mainly in the microchromosome set. on the contrary, the macrochromosomes were highly conservative. Although consistent karyotypic diversity occurred in the torquatus group, the cytogenetic data obtained up to now did not allow us to clarify the phylogenetic relationships of the species. Nevertheless, the geographical distribution of the distinct cytotypes in T. hispidus and T. torquatus suggested that more than one species might be involved in each case.

Cotton Rats (Sigmodon hispidus) and Black Rats (Rattus rattus) as Possible Reservoirs of Leishmania spp. in Lara State, Venezuela

A total of 519 wild animals belonging to eleven species were collected during a two year study in a cutaneous leishmaniasis endemic area in Venezuela (La Matica, Lara State). The animals were captured in home-made Tomahawk-like traps baited with maize, bananas or other available local fruits, and parasites were isolated from 27 specimens. Two different species were found naturally infected with flagellates, i.e., cotton rats (Sigmodon hispidus) and black rats (Rattus rattus). Characterization of the parasites using PCR, kDNA restriction pattern and hybridization with species-specific probes revealed the presence of Leishmania (L.) mexicana in three of the black rats and Leishmania (V.) braziliensis in two others. The latter species was also identified in the single positive specimen of S. hispidus. The results suggested both species of animals as possible reservoirs of Leishmania sp.