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The greatest threats to terrestrial reptiles are urban development and habitat modification. In this sense, a better understanding of folliculogenesis in these animals would be important to knowledge of reproductive biology. The aim of this study was to analyze the correlation between the thickness of the granulosa cell layer and the expression of the active caspase-3 protein in the previtellogenic and vitellogenic follicles of T. hispidus and T. semitaeniatus. Ovaries were used for histological (morphology and morphometry: thickness of granulosa layer) and immunohistochemical (active caspase-3 expression) analyses. The previtellogenic follicles of T. hispidus and T. semitaeniatus showed a thicker granulosa layer, with pyriform and small cells. The vitellogenic follicles had a monolayer of cuboid cells, and a thicker thecal layer. The thickness of the granulosa layer was significantly higher in the previtellogenic compared to the vitellogenic phase for both species. However, no differences were observed between the species. Active caspase-3 was observed in the pyriform and intermediate cells in previtellogenesis of T. hispidus and T. semitaeniatus. Nevertheless, no immunostaining was observed in the vitellogenic phase in both species. In conclusion, this study shows that the thickness of the granulosa cell layer is higher in the previtellogenic follicles compared to the vitellogenic follicles in the two Tropidurus species. Pyriform and intermediate cells from previtellogenic follicles show high expression of the protein, indicating that remodeling of the epithelium is associated with apoptosis. Finally, our results provide a scientific basis for assisted reproductive techniques and conservation actions to the reptiles in the future., Las mayores amenazas para los reptiles terrestres son el desarrollo urbano y la modificación del hábitat. En este sentido, una mejor comprensión de la foliculogénesis en estos animales sería importante para el conocimiento de la biología reproductiva. El objetivo de este estudio fue analizar la correlación entre el grosor de la capa de células de la granulosa y la expresión de la proteína caspase-3 activa en los folículos previtelogénicos y vitelogénicos de T. hispidus y T. semitaeniatus. Los ovarios se usaron para análisis histológicos (morfología y morfometría: grosor de la capa de la granulosa) e inmunohistoquímicos (expresión activa de caspase-3). Los folículos previtelogénicos de T. hispidus y T. semitaeniatus mostraron una capa de granulosa más gruesa, con células piriformes y pequeñas. Los folículos vitelogénicos tenían una monocapa de células cuboides y una capa tecal más gruesa. El grosor de la capa de granulosa fue significativamente mayor en la fase previtelogénica en comparación con la fase vitelogénica para ambas especies. Sin embargo, no se observaron diferencias entre las especies. Se observó caspase-3 activa en las células piriformes e intermedias en previtelogénesis de T. hispidus y T. semitaeniatus. Sin embargo, no se observó inmunotinción en la fase vitelogénica en ambas especies. En conclusión, este estudio muestra que el grosor de la capa de células de la granulosa es mayor en los folículos previtelogénicos en comparación con los folículos vitelogénicos en las dos especies de Tropidurus. Las células piriformes e intermedias de folículos previtelogénicos muestran una alta expresión de la proteína, lo que indica que la remodelación del epitelio está asociada con la apoptosis. Finalmente, nuestros resultados proporcionan una base científica para técnicas de reproducción asistida y acciones de conservación para los reptiles en el futuro., Asociación Herpetológica Argentina

Tropidurus cocorobensis Rodrigues, 1987. Brazil, state of Pernambuco, municipality of Floresta (08°36'04" S; 38°34'07" W; 316 m). Collectors: Members of the Wildlife Rescue Team from the Project of Integration of São Francisco river (PISF) with the basins of septentrional northeastern. From July 2009 to February 2010, 55 specimens were collected in areas of Caatinga characterized by shrub vegetation with sandy soil, and deposited in the Scientific Collection of the Centro de Conservação e Manejo de Fauna da Caatinga – CEMAFAUNA-CAATINGA/UNIVASF, Petrolina, Brazil. Axis East Transposition of the São Franscisco river – Petrolândia (Leste Petrolândia: LPE) (LPE 998).

This work evaluates the diet and the reproductive cycle of Tropidurus torquatus in relation to seasonality in a rock outcrop formations in a remaining area of Atlantic Rainforest. The data indicate that the lizards feed mainly on arthropods and plant material. The female reproductive activity varies between seasons, while males contain spermatozoids throughout the year. The minimum body size at maturity of the individuals was larger when compared to other population of the same species studied by other authors. The data obtained in the present study confirm previous observations about the different patterns in diet composition and reproductive cycles of each population of this species in different latitude and occurrence areas, and provide the first study about this theme for T. torquatus in rock outcrops in Atlantic Forest of Minas Gerais state.

This work evaluates the diet and the reproductive cycle of Tropidurus torquatus in relation to seasonality in a rock outcrop formations in a remaining area of Atlantic Rainforest. The data indicate that the lizards feed mainly on arthropods and plant material. The female reproductive activity varies between seasons, while males contain spermatozoids throughout the year. The minimum body size at maturity of the individuals was larger when compared to other population of the same species studied by other authors. The data obtained in the present study confirm previous observations about the different patterns in diet composition and reproductive cycles of each population of this species in different latitude and occurrence areas, and provide the first study about this theme for T. torquatus in rock outcrops in Atlantic Forest of Minas Gerais state. En este estudio se evalúa la dieta y el ciclo reproductivo de Tropidurus torquatus en relación con la estacionalidad en en un afloramiento rocoso de la Mata Atlántica. Los datos recogidos indican que los lagartos se alimentan principalmente de artrópodos y materia vegetal. La actividad reproductiva de las hembras varía entre temporadas, mientras que los machos contenía esperma durante todo el año. El tamaño mínimo de ejemplares reproductivamente activos fue mayor en comparación a la encontrada por otros autores para esta especie en otras localidades. Los datos obtenidos en este estudio confirman observaciones previas sobre los diferentes patrones en composición de dieta y ciclos reproductivos de cada población de esta especie en diferentes latitudes y áreas de ocurrencia, y proporcionan el primer estudio sobre este tema para T. torquatus en un afloramiento rocoso de la Mata Atlántica del estado de Minas Gerais.

This study assessed the reproductive and fat body cycles of Tropidurus hispidus (Spix, 1825) and T. semitaeniatus (Spix, 1825) in an area of caatinga in the Serido of Rio Grande do Norte, Brazil, from October 2006 to May 2008. In both species, the females were reproductively active from the middle of the dry season to the beginning of the rainy season. Female reproductive activity was influenced by precipitation, whereas males exhibited spermatozoa in their testes throughout the year, and their reproductive activity was not related to any of the climatic variables analyzed. Mean clutch size (± SD) was 8.1 ± 2.0 and 2.1 ± 0.6 eggs in T. hispidus and T. semitaeniatus, respectively, and was significantly related to female body size only in T. hispidus. The fat stock varied inversely with reproductive activity in the two species, and there was no difference in fat body mass between females and males. The effects of precipitation on the length of the breeding season of these two Tropidurus species suggest that their reproductive cycles are related to the microclimatic conditions suitable for embryo development, as well as for the neonates' emergence and survival especially during the rainy season, which may offer greater food availability to the hatchlings. Este estudio evaluó los ciclos reproductivos y de grasa corporal de Tropidurus hispidus (Spix, 1825) y T. semitaeniatus (Spix, 1825) en una área de caatinga en el Seridó de Rio Grande do Norte, Brasil, de octubre de 2006 a mayo de 2008. En ambas especies, las hembras se encontraron reproductivamente activas a partir de mediados de la estación seca para el inicio de la temporada de lluvias. La actividad reproductiva de las hembras fue influenciada por las precipitaciones, mientras que los machos presentaron espermatozoides en los testículos durante todo el año, y su actividad reproductiva no fue relacionada con ninguna de las variables climáticas analizadas. El tamaño medio (± DE) de la nidada fue de 8.1 ± 2.0 y 2.1 ± 0.6 huevos en T. hispidus y T. semitaeniatus, respectivamente, y se relacionó significativamente con el tamaño corporal de la hembra solo en T. hispidus. La reserva de grasa varió inversamente con la actividad reproductiva en las dos especies, y no hubo diferencia en la cantidad de grasa corporal entre hembras y machos. Los efectos de la precipitación sobre la duración de la temporada reproductiva de estas dos especies de Tropidurus sugieren que sus ciclos reproductivos están relacionados con las condiciones microclimáticas adecuadas para el desarrollo del embrión, así como para la emergencia de los recién nacidos y su supervivencia, especialmente durante la temporada de lluvias, que es la que puede ofrecer una mayor disponibilidad de alimentos para las crías.

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. Este estudo objetivou analisar a variação sazonal na composição da dieta e no comportamento de forrageamento de Tropidurus hispidus (Spix, 1825) e T. semitaeniatus (Spix, 1825) e medir a intensidade de forrageamento (número de movimentos, tempo gasto parado, distância percorrida e número de ataques sobre itens-presa) destas espécies em uma área do bioma caatinga no estado do Rio Grande do Norte, Brasil. Hymenoptera/Formicidae e Isoptera predominaram na dieta de ambas as espécies durante a estação seca. A predação oportunística de larvas de Lepidoptera, larvas/adultos de Coleoptera e ninfas/adultos de Orthoptera ocorreu na estação chuvosa, contudo as formigas foram os itens-presa mais importantes. O número de itens alimentares foi similar entre as espécies de lagartos em ambas as estações; no entanto a sobreposição para o número de presas foi menor na estação chuvosa. As presas ingeridas durante a estação chuvosa por T. hispidus foram maiores do que aquelas de T. semitaeniatus. As comparações sazonais da intensidade de forrageamento entre as duas espécies mostraram diferenças, principalmente na estação chuvosa, quando T. hispidus apresentou menos movimentos e ataques sobre presas, e mais tempo gasto parado comparado a T. semitaeniatus. Embora ambos os lagartos sejam forrageadores senta-e-espera, T. semitaeniatus é mais ativo do que T. hispidus. A dieta e o comportamento de forrageamento de T. hispidus e T. semitaeniatus mostram sobreposição sob condições limitantes durante a estação seca, e são fatores segregativos que podem contribuir para a coexistência dessas espécies na estação chuvosa.

Although Tropidurus is a widely distributed lizard genus in South America and the Galapagos Islands, studies on space use and spatial distribution are scarce. We studied the home range structure of the saxicolous lizard Tropidurus torquatus based on the inland population of a rock outcrop in Minas Gerais State, southeastern Brazil. Lizards were individually marked and observed during reproductive and non-reproductive seasons. Using the mínimum convex polygon method, we found that average total range size of males during the reproductive season was larger than that of females, and that both had similar total range sizes in the non-reproductive season. The harmonic mean method showed that males have a larger home range size than that of females during both seasons. As expected for a polygynous species, the average number of males whose total ranges overlapped those of females tended to be higher in the reproductive season than in the non-reproductive season. Intrasexually, the number of females whose total ranges were associated with those of other females was also higher in the reproductive season than in the non-reproductive season. For males, this number remained low in both seasons, suggesting that males use more exclusive areas, whereas the smaller total ranges of females apparently sustain a higher density of individual s during the reproductive season. Frequency of microhabitat use in relation to vegetation increased in the non-reproductive season and the activity patterns of lizards shifted from bimodal in the reproductive season (rainy period) to unimodal in the non-reproductive season (dry period). Thus, the range structure, microhabitat use, and activity patterns of the T. torquatus observed here were all influenced by the time frame affecting their spatial ecology.

Although Tropidurus is a widely distributed lizard genus in South America and the Galapagos Islands, studies on space use and spatial distribution are scarce. We studied the home range structure of the saxicolous lizard Tropidurus torquatus based on the inland population of a rock outcrop in Minas Gerais State, southeastern Brazil. Lizards were individually marked and observed during reproductive and non-reproductive seasons. Using the mínimum convex polygon method, we found that average total range size of males during the reproductive season was larger than that of females, and that both had similar total range sizes in the non-reproductive season. The harmonic mean method showed that males have a larger home range size than that of females during both seasons. As expected for a polygynous species, the average number of males whose total ranges overlapped those of females tended to be higher in the reproductive season than in the non-reproductive season. Intrasexually, the number of females whose total ranges were associated with those of other females was also higher in the reproductive season than in the non-reproductive season. For males, this number remained low in both seasons, suggesting that males use more exclusive areas, whereas the smaller total ranges of females apparently sustain a higher density of individual s during the reproductive season. Frequency of microhabitat use in relation to vegetation increased in the non-reproductive season and the activity patterns of lizards shifted from bimodal in the reproductive season (rainy period) to unimodal in the non-reproductive season (dry period). Thus, the range structure, microhabitat use, and activity patterns of the T. torquatus observed here were all influenced by the time frame affecting their spatial ecology. Aunque Tropidurus es un género de lagarto extensamente distribuido en Sudamérica y en las islas Galápagos, son escasos los estudios sobre uso del espacio y distribución espacial. En este trabajo se estudió la organización espacial del lagarto saxícola Tropidurus torquatus basado en la población interiorana de uno afloramiento rocoso en el estado de Minas Gerais, sudeste del Brasil. Los lagartos fueron individualmente marcados y observados durante las estaciones reproductiva y no reproductiva. Con el método del mínimo polígono convexo fue encontrado que el tamaño promedio del dominio vital de los machos durante la estación reproductiva fue más grande que el de las hembras y en la estación no reproductiva hembras y machos mantuvieron dominios vitales similares en el tamaño. El método de la media armónica mostró que el tamaño promedio del area de vida de machos fue mayor que el area de las hembras en ambas estaciones. Como esperado para una especie poligínica, el número medio de machos con dominios vitales sobrepuestos a los de las hembras tendió a ser más grande en la estación reproductiva. Intrasexualmente, el número de hembras con sus dominios vitales asociados a los de otras hembras también fue mayor en la estación reproductiva. Para los machos, este número permaneció bajo en ambas estaciones, lo que sugiere que los machos usan areas más exclusivas, mientras los dominios vitales más pequeños de las hembras al parecer sostengan una mayor densidad de individuos durante la estación reproductiva. La frecuencia de uso de los microhábitats relacionados a la vegetación aumentó en la estación no reproductiva y el padrón de actividad de los lagartos cambió del bimodal en la estación reproductiva (período lluvioso) para unimodal en la no reproductiva (período seco). Así la organización espacial, la utilización de los microhábitats y los padrones de actividad de T. torquatus aquí observados fueron todos influenciados por el período de tiempo afectando la ecología espacial de los lagartos.