Do restinga cnemidophorine lizards run on empty along the Brazilian coast? / Os lagartos cnemidophorine de restinga correm no vazio ao longo da costa brasileira?

Abstract The number of individuals with empty stomachs in a population (i.e. the proportion of individuals "running on empty") can be used as a simple index of instantaneous energy balance of some organisms such as lizards and fishes. In this study, we aimed to analyze the proportion of empty stomachs in 16 populations of five cnemidophorine species (Glaucomastix abaetensis, Ameivula ocellifera, Glaucomastix littoralis, Contomastix lacertoides and Ameivula nativo) along approximately 5,000 km the Brazilian coast. A total of 550 individuals had their stomach contents removed and identified in the laboratory. Our results showed that the proportion of individuals "running on empty" varied from 0 to 11.1% among the different populations and species. These proportions are suggestive that the five studied species would be in an overall positive energy balance at the time of the study.

Resumo O número de indivíduos com estômagos vazios em uma população (i.e. a proporção de indivíduos "correndo no vazio") pode ser usado como um índice simples do balanço energético instantâneo de organismos como lagartos e peixes. Este estudo teve como objetivo analisar a proporção de estômagos vazios em 16 populações pertencentes a cinco espécies de cnemidophorines (Glaucomastix abaetensis, Ameivula ocellifera, Glaucomastix littoralis, Contomastix lacertoides e Ameivula nativo) ao longo de cerca de 5,000 km da costa leste do Brasil. Um total de 550 indivíduos tiveram seus conteúdos estomacais removidos e analisados em laboratório. Nossos resultados mostraram que a proporção de indivíduos "correndo no vazio" variou entre 0 a 11.1% entre as diferentes populações e espécies. Essas proporções sugerem que as cinco espécies estudadas estariam em geral em um balanço energético positivo, quando da realização deste estudo.

Do restinga cnemidophorine lizards run on empty along the Brazilian coast?

Abstract The number of individuals with empty stomachs in a population (i.e. the proportion of individuals running on empty) can be used as a simple index of instantaneous energy balance of some organisms such as lizards and fishes. In this study, we aimed to analyze the proportion of empty stomachs in 16 populations of five cnemidophorine species (Glaucomastix abaetensis, Ameivula ocellifera, Glaucomastix littoralis, Contomastix lacertoides and Ameivula nativo) along approximately 5,000 km the Brazilian coast. A total of 550 individuals had their stomach contents removed and identified in the laboratory. Our results showed that the proportion of individuals running on empty varied from 0 to 11.1% among the different populations and species. These proportions are suggestive that the five studied species would be in an overall positive energy balance at the time of the study.

Resumo O número de indivíduos com estômagos vazios em uma população (i.e. a proporção de indivíduos correndo no vazio) pode ser usado como um índice simples do balanço energético instantâneo de organismos como lagartos e peixes. Este estudo teve como objetivo analisar a proporção de estômagos vazios em 16 populações pertencentes a cinco espécies de cnemidophorines (Glaucomastix abaetensis, Ameivula ocellifera, Glaucomastix littoralis, Contomastix lacertoides e Ameivula nativo) ao longo de cerca de 5,000 km da costa leste do Brasil. Um total de 550 indivíduos tiveram seus conteúdos estomacais removidos e analisados em laboratório. Nossos resultados mostraram que a proporção de indivíduos correndo no vazio variou entre 0 a 11.1% entre as diferentes populações e espécies. Essas proporções sugerem que as cinco espécies estudadas estariam em geral em um balanço energético positivo, quando da realização deste estudo.

Ámbito hogareño de Aspidoscelis cozumela(Squamata, Teiidae): una lagartija partenogenética microendémica de Isla Cozumel, México / Home range of Aspidoscelis cozumela (Squamata: Teiidae): a parthenogenetic lizard microen-demic to Cozumel Island, México

Home range is defined as the area within which an individual moves to acquire resources necessary to increase their fitness and may vary inter and intra-specifically with biotic and abiotic factors. This study details the home range of the parthenogenic lizard, Aspidoscelis cozumela,an active forager microendemic to Cozumel Island, México, with high preference for open sand beaches. The home range of A. cozumelawas compared with other species of Aspidoscelis(gonochoric and parthenogenetic) and other lizards that occupy coastal habitats. Furthermore, the biotic and abiotic factors that may influence home range were analyzed. This study was conducted in the beach located on the East side of the island (area of 4 000 m2) that is composed primarily of halophyte vegetation with high levels of sunlight. From 1999 to 2001, nine samples were taken which included the dry, rainy, "nortes", and breeding seasons. During each sampling, capture-mark-recapture techniques were conducted and the date, time of day, and snout-vent length (SVL) were recorded to the nearest millimeter. Individuals were located in the study area using a bi-coordinate reference using 10 x 10 m subdivisions of the habitat. Home range and home range overlap were calculated using the convex polygon method in McPaal and home range/SVL correlation was tested using Pearson's correlation. To calculate females home range, three or more recaptures were considered. A total of 20 home ranges that averaged 45.1 ± 14.0 m2 were obtained and no correlation between SVL and home range size was detected (p = 0.9229, n = 20). However, removing individuals with outlier home ranges (females with home ranges > 100 m2, n = 2) resulted in a positive correlation with SVL (r = 0.61, p = 0.0072, n = 18). A 22.9 ± 5.7% overlap in home range was also detected. The small home range of A. cozumelarepresents the smallest home range within the Aspidoscelisgenus recorded to date (including both parthenogenetic and gonochoric species) and contrasts the theoretical predictions of broad home ranges for widely foraging species. Thermoregulatory benefits and a high population density may explain the small home range of A. cozumela.Although this species is highly adapted to the environmental conditions present on the open sand beaches, anthropogenic effects on these habitats by the development of tourism infrastructure may jeopardize their existence on Cozumel Island.

El ámbito hogareño es el área dentro de la cual un individuo se mueve para adquirir recursos que incrementen su supervivencia. El ámbito hogareño puede variar, intra e interespecíficamente, por factores bióticos y abióticos. En este trabajo se estudió el ámbito hogareño de la lagartija partenogenética Aspidoscelis cozumela,una especie de forrajeo amplio, con alta preferencia por las playas y microendémica de Isla Cozumel, México. El ámbito hogareño de A. cozumelase comparó con otras especies de Aspidoscelis(gonocóricas y partenogenéticas) y con otras lagartijas que ocupan hábitats costeros. Además, se discuten los factores bióticos y abióticos que lo moldean. La zona de estudio fue una playa (con un área de 4 000 m2), que se encuentra al Este de la isla y que presenta vegetación halófita (expuesta a altos niveles de insolación). De 1999 al 2001 se realizaron nueve censos que cubrieron la época de sequía, de lluvias y la época de "nortes" de la zona y la temporada de reproducción de A. cozumela.Durante cada censo, se realizó captura-marcaje-recaptura y se registró: fecha, hora del día, longitud hocico-cloaca (LHC) al milímetro más cercano. Los individuos fueron ubicados en el área de estudio por bi-coordenadas usando estacas como referencia. El ámbito hogareño se calculó con el método del polígono convexo con el programa McPaal, adicional-mente se calculó el solapamiento del ámbito hogareño. Se relacionó la LHC con el ámbito hogareño. Para el cálculo del ámbito hogareño se consideraron las hembras con tres o más recapturas. Se obtuvieron 20 ámbitos hogareños, que promediaron 45.1 ± 14.0 m2. No se encontró relación de la LHC con el ámbito hogareño (p = 0.9229, n = 20). Sin embargo, un análisis que excluyó los individuos con los ámbitos hogareños extremos, mostró que el ámbito hogareño de A. cozumelase relacionó de manera positiva con la LHC (p = 0.0072, n = 18), las hembras más grandes tuvieron ámbitos hogareños más amplios. El solapamiento del ámbito hogareño fue de 22.9 ± 5.7%. El ámbito hogareño de A. cozumelaes el más pequeño que se ha documentado en el género Aspidoscelis(incluyendo especies partenoge-néticas y gonocóricas) y se contrapone con las predicciones teóricas que establecen ámbitos hogareños amplios para especies de forrajeo amplio. Beneficios térmicos y una elevada densidad poblacional pueden explicar la marcada residencia en las playas y ámbito hogareño reducido de A. cozumela.La lagartija partenogenética A. cozumelaestá bien adaptada a las condiciones ambientales en las playas, sin embargo las afectaciones severas en las playas por el desarrollo de la infraestructura turística pueden poner en riesgo su existencia en Isla Cozumel.

Cambio estacional en la coloración dorsal de la lagartija Aspidoscelis costata costata (Squamata: Teiidae) / Seasonal changes in the dorsal coloration in the lizard Aspidoscelis costata costata (Squamata: Teiidae)

Seasonal changes in the dorsal coloration in the lizard Aspidoscelis costata costata (Squamata: Teiidae). Color and color patterns in animals are important characteristics that bring protection, by dampening the ability of predators that depend on their sight to detect their preys. In lizards, the dorsal coloration plays a key role in communication of intraspecific signals such as social cues. In this study, we evaluated the seasonal changes in the dorsal coloration of the wide foraging lizard A. costata costata, in Tonatico, State of Mexico, Mexico. The seasonal evaluation included: the rainy season from mid June to mid September (can also include the end of May to early October); and the dry season for the rest of the year. The dorsal coloration of A. costata costata and their microhabitats were evaluated by contrasting the color pattern with an identification guide and the control colors of Pantone®, during 11 samplings carried out from February-October 2007. Individual lizard analysis recorded snout-vent length, sex and stage (juveniles and adults). Besides, all animals were marked by toe-clipping, allowing to distinguish dorsal coloration between seasons, sex and stage. A total of 95 lizards were analyzed (53 and 42 for the dry and rainy seasons respectively). We found that the dorsal coloration in A. costata costata varies seasonally and with microhabitats: during the dry season individuals show a brown coloration whereas during the rainy season becomes greener, as the background dominant vegetation color. The results of the present study suggest that: 1) the variation in dorsal coloration in A. costata costata plays an important role in the survival (by cryptic camouflage) of this widely foraging species; 2) the changes in the dorsal coloration of A. costata costata are individually expressed traits, since the coloration of the same lizard is either brown or green depending on the season; and 3) the cryptic functions of the dorsal coloration in widely foraging species have been largely underestimated. We discuss the possible influence of the changes in coloration in an habitat that changes drastically between both dry and rainy seasons.

En lagartijas la coloración corporal es importanteen la comunicación así como en la protección contra los depredadores. Con el uso de una guía Pantone®, se analizó el cambio estacional en la coloración dorsal y los microhábitats de Aspidoscelis costata costata, una lagartija de amplio forrajeo que habita un ambiente (en el Estado de México, México) que cambia drásticamente de apariencia entre sequía y lluvias. Se analizó la dependencia de la coloración dorsal de acuerdo a la estación, sexo y estadio de desarrollo. Los resultados indican que la lagartija A. costata costata presenta una coloración dorsal similar al sustrato en cada estación: parda en sequía y principalmente verde en lluvias. Este estudio sugiere: 1) Que la variación en coloración dorsal con funciones crípticas, como la registrada en A. costata costata, puede resultar importante en la supervivencia de especies de amplio forrajeo; 2) Que el cambio en la coloración dorsal en A. costata costata es a nivel individual, ya que un individuo presente en ambas estaciones manifiesta una coloración dorsal parda en la estación de sequía y una coloración dorsal verde en la estación de lluvias y 3) Que la coloración dorsal, con funciones crípticas, está subestimada en especies de amplio forrajeo.

A first record of Amblyomma dissimile (Acari: Ixodidae) parasitizing the lizard Ameiva ameiva (Teiidae) in Brazil / Primeiro registro de Amblyomma dissimile (Acari: Ixodidae) parasitando o lagarto Ameiva ameiva (Teiidae) no Brasil

A non-engorged adult female Amblyomma dissimile and two Amblyomma sp. larvae were found parasitizing the lizard Ameiva ameiva in the municipality of Chapadinha, State of Maranhão. This is the first record in the state of Maranhão and fills a gap in the distribution of A. dissimile in Brazil. The lizard A. ameiva represents a new host for A. dissimile, and also the first record of this tick species infesting lizards of the family Teiidae in Brazil.

Uma fêmea adulta não ingurgitada de Amblyomma dissimile e duas larvas de Amblyomma sp. foram encontradas parasitando o lagarto Ameiva ameiva no município de Chapadinha, Estado do Maranhão. Além de representar um novo registro para o Estado do Maranhão, esse trabalho preenche uma lacuna de distribuição geográfica de A. dissimile no país. O lagarto A. ameiva representa um novo hospedeiro para A. dissimile, sendo também o primeiro registro dessa espécie de carrapato infestando lagartos da família Teiidae no Brasil.

Variación morfológica de la lagartija partenogenética Aspidoscelis rodecki (Squamata: Teiidae): implicaciones evolutivas y de conservación

Morphologic variation of the parthenogenetic lizard Aspidoscelis rodecki (Squamata: Teiidae): evolutionary and conservation implications. Post-formational divergence has been used for the recognition of new parthenogenetic species. Currently, the parthenogenetic lizard Aspidoscelis rodecki McCoy and Maslin 1962 is recognized as a single taxon that was derived from a single, parthenogenetically capable, hybrid. This lizard had been derived via hybridization between individuals of two gonochoristic species, Aspidoscelis angusticeps Cope 1878 and Aspidoscelis deppii Wiegmann 1834. The distribution of A. rodecki includes Isla Contoy and Isla Mujeres and the adjacent mainland of Quintana Roo, México. Previous studies have found post-formational divergence in genetic, chromatic and life-history characteristics among a continental population (Puerto Juárez) and an insular population (Isla Contoy). A meristic analysis was carried out to evaluate the morphological divergence among both populations of A. rodecki. We used 38 individuals from Puerto Juárez and 23 individuals from Isla Contoy. Nine meristic characters with discrimination value among species of the genus Aspidoscelis were used in both univariate (t-Student) and multivariate analyses (principal components and canonical variate analysis). According to both analyses, Puerto Juárez is meristically distinguishable from Isla Contoy. Both populations differ in five meristic characters and were a high correct classification in the canonical variate analysis: 97% of Puerto Juárez and 100% of Isla Contoy. A small sample from Isla Mujeres and a single specimen from Punta Sam (mainland) may represent different morphological groups. Due to the patterns of phenotypic variation, A. rodecki is considered as a single variable parthenogenetic species with high priority to conservation. The populations of A. rodecki have been extremely affected by the tourism developers. If the habitat of the parthenogenetic lizard (beach grasses) is allowed to stay, the expansion by the developers will not affect the survivorship of these populations. Nevertheless, the first sign of development is the total destruction of natural grasses that occurs on the beach, leaving only sand. There is a last chance to save the parthenogenetic lizard A. rodecki, but any effort will be useless without the support from the environmental authority of Mexico and cooperation from the developers. We suggest that Puerto Juárez and Isla Contoy receive separate management because they have unique portions of phenotypic variation of A. rodecki. The two lizard populations can be considered separate "Evolutionary Significant Units" (ESU). Rev. Biol. Trop. 56 (4): 1871-1881. Epub 2008 December 12.

La divergencia post-formación se ha utilizado para el reconocimiento de nuevas especies partenogenéticas. Actualmente, la lagartija partenogenética Aspidoscelis rodecki McCoy y Maslin 1962 es reconocida como una sola especie, que se originó de un híbrido partenogenético. Estudios previos han encontrado divergencia genética, en coloración y en características de historia de vida entre una población continental (Puerto Juárez) y una insular (Isla Contoy) en Quintana Roo, México. Se llevó a cabo un análisis merístico para evaluar la divergencia entre ambas poblaciones de A. rodecki. Se utilizaron 38 individuos de Puerto Juárez y 23 individuos de Isla Contoy. Se usaron nueve características merísticas y se realizaron análisis univariados (t de Student) y multivariados (análisis de componentes principales y análisis de variación canónica). De acuerdo a ambos análisis, Puerto Juárez es merísticamente distinguible de Isla Contoy. Ambas poblaciones difieren en cinco características merísticas y presentaron un alto porcentaje de clasificación en el análisis de variación canónica: 97% para Puerto Juárez y 100% para Isla Contoy. Una pequeña muestra de Isla Mujeres y un solo individuo de Punta Sam (continente) pueden representar otros grupos morfológicos. Con base en los patrones de variación fenotípica, A. rodecki es considerada como una sola especie partenogenética variable y prioritaria para la conservación. Debido a que cada población contiene una porción única de la variación de A. rodecki, Puerto Juárez e Isla Contoy merecen un manejo separado y se sugiere que cada una constituya una "Unidad Evolutiva Significativa" (ESU).

Genética e hematologia de lagartos do gênero tupinambis (sauria: teiidae) / Genetics and hematology of lizards of the genus tupinambis (Sáuria: Teiidae)

Os teiús são os maiores lagartos predadores da América do Sul, os maiores lagartos do Novo Mundo e os maiores representantes da família Teiidae; portanto, seu papel na cadeia alimentar e no equilíbrio de um ecossistema é fundamental. Todas as espécies de teiús ocorrem no território brasileiro, sendo duas delas endêmicas. Este artigo teve como objetivo caracterizar lagartos do gênero Tupinambis por meio da genética e da hematologia. Foram analisados 17 animais de cativeiro de cinco espécies de teiús, sendo oito Tupinambis merianae, quatro T. rufescens, três T. quadrilineatus, um T. teguixin e um T. duseni. No que concerne à hematologia, foram analisados hematócrito, dosagem de hemoglobina, contagem de eritrócitos, volume corpuscular médio, hemoglobina corpuscular média e concentração da hemoglobina corpuscular média. Os resultados mostraram que ocorreu diferença entre as espécies em todas as variáveis hematológicas. A partir da técnica eletroforética em acetato de celulose (tampão Borato pH 8,9), foram identificados os padrões de hemoglobina de quatro espécies de teiús (T. merianae, T. rufescens, T. quadrilineatus e T. teguixin)...

Genetics and hematology of lizards of the genus Tupinambis (Sauria:Teiidae). Tegus are the largest predator lizards in South America, the largest terrestrial lizards of the New World and the largest members of the family Teiidae; the refore its role in the food chain and inside an ecosystem balance is essential. All tegus species occur in Brazilian territory, and two of them are endemic. This work aimed to characterize animals through genetics and hematology. 17 animals of 5 tegus species were analyzed, being 8 Tupinambis merianae, 4 Tupinambis rufescens, 3 Tupinambis quadrilineatus, 1 Tupinambis teguixin and 1 Tupinambis duseni. In hematology were analyzed hematocrit, hemoglobine dosage, erythrocyte count, average body volume, average body hemoglobin and average body hemoglobin concentration. The results showed that occurs differences between the species in all of hematology variables. Throught electrophoretic techniques in cellulose acetate (Borato pH 8,9), hemoglobin patterns were identified four tegus species (T. merianae, T. rufescens, T. quadrilineatus and T. teguixin)...