RESUMO

The Mabuyinae subfamily exhibits remarkable diversity, encompassing 26 genera and 236 currently recognized species. Traditionally, the entire range of the group was attributed to the single genus Mabuya, which had a wide distribution along tropical regions of the Planet. In recent studies, phylogenetic hypotheses based on molecular data have identified four major groups, which have been further divided into geographically distinct clades. At least two phylogenetically distinct lineages of Mabuyinae are distributed in the Neotropical Region: Trachylepis atlantica and the remaining 16 genera within the Mabuyinae clade from the mainland and the Caribbean islands. Our understanding of Mabuyinae osteology is still quite limited, particularly concerning interspecific variation. This lack of information hinders our ability to make strong contributions to the phylogenetic relationships within this group or even to confirm the existence of certain new taxa considering their relatively conserved external morphology. This work provides a comprehensive anatomical reference for the adult skull of Neotropical Mabuyinae lizards, highlighting osteological features that might be useful for delimiting each genus. This descriptive guide includes illustrations and employs multiple techniques, such as dry preparation, clearing and staining, and high-resolution computerized microtomography. Our results provide additional diagnostic characteristics that include specific cranial bone arrangements, dental patterns, and cranial adaptations, such as dorsoventral head flattening, and their functional implications for bite force and cranial biomechanics. This study reinforces the importance of cranial morphology in understanding the phylogenetic relationships and evolutionary trajectories of New World Mabuyinae lizards, advocating for broader morphological sampling to enrich our understanding of these diverse reptiles.

RESUMO

Solar ultraviolet (UV) radiation is an environmental genotoxic factor linked to amphibian decline. Here we assessed the genotoxic risk of UVB and UVA exposure for tadpoles from open ponds in southern Brazil, a mid-latitude region influenced by stratospheric ozone depletion. Daily UV doses were measured on the surface of a pond in Taim Ecological Station (TAIM; 32°49'24''S; 52°38'31''W) on a cloudless summer day to predict the worst-case scenario for UV-induced DNA damage. Pond descriptors were related to the use of microhabitats by Boana pulchella tadpoles in two ponds over the climate seasons of 2013 and 2014. Our results indicate that shaded microhabitats were more frequent than unshaded ones in autumn, winter, and spring but not in summer. Hence, the penetration of UV radiation into the water of unshaded microhabitats was evaluated through laboratory experiments with artificial UV sources and pond water samples. Physical and biological sensors were applied in the experiments to measure the incident UV radiation and its genotoxic action. By integrating field and laboratory data, we demonstrate that low doses of biologically effective UV radiation reached the tadpoles in autumn, winter, spring, and early summer due to a high proportion of shaded microhabitats and a high concentration of solids in unshaded microhabitats. However, the relative reduction of shaded microhabitats jointly with a declining water level in late summer may have exposed tadpoles to high UV doses. Our experiments also indicate that solar UVB radiation, but not UVA, is primarily responsible for the induction of DNA pyrimidine dimers in organisms living under the surface of aquatic ecosystems. The present work highlights the determinant role of wetland descriptors for minimizing the genotoxic potential of UV radiation and its consequences for amphibians.

Assuntos

RESUMO

Understanding how different environmental factors influence species occurrence is a key issue to address the study of natural populations. However, there is a lack of knowledge on how local traits influence the microhabitat use of tropical arboreal lizards. Here, we investigated the microhabitat selection of the poorly known lizard Tropidurus lagunablanca(Squamata: Tropiduridae) and evaluated how environmental microhabitat features influence animals presence. We used a Resource Selection Function approach, in a case/control design where we analyzed the effect of substrate temperature and trees diameter at breast height (DBH) in the probability of presence of lizards using mixed Conditional Logistic Regression. We found that T. lagunablanca uses trees with DBH from 0.40 m to 4 m and substrate temperatures ranging from 25.9°C to 42°C. Moreover, we showed that thickness of the trees and substrate temperatures significantly increased the probability of presence of T. lagunablanca individuals, being the probability of presence higher than 50% for trees up to 1.5 m DBH and temperature of substrate up to 37.5°C. Our study probed that T. lagunablanca individuals choose trees non-randomly, selecting thicker and warmer tree trunks. This information advances the knowledge of the spatial ecology of Neotropical arboreal lizards and is relevant for conservation, putting an emphasis on preserving native vegetation in the Pantanal.(AU)

Assuntos

RESUMO

Abstract Understanding how different environmental factors influence species occurrence is a key issue to address the study of natural populations. However, there is a lack of knowledge on how local traits influence the microhabitat use of tropical arboreal lizards. Here, we investigated the microhabitat selection of the poorly known lizard Tropidurus lagunablanca (Squamata: Tropiduridae) and evaluated how environmental microhabitat features influence animal's presence. We used a Resource Selection Function approach, in a case/control design where we analyzed the effect of substrate temperature and tree's diameter at breast height (DBH) in the probability of presence of lizards using mixed Conditional Logistic Regression. We found that T. lagunablanca uses trees with DBH from 0.40 m to 4 m and substrate temperatures ranging from 25.9°C to 42°C. Moreover, we showed that thickness of the trees and substrate temperatures significantly increased the probability of presence of T. lagunablanca individuals, being the probability of presence higher than 50% for trees up to 1.5 m DBH and temperature of substrate up to 37.5°C. Our study probed that T. lagunablanca individuals choose trees non-randomly, selecting thicker and warmer tree trunks. This information advances the knowledge of the spatial ecology of Neotropical arboreal lizards and is relevant for conservation, putting an emphasis on preserving native vegetation in the Pantanal.

RESUMO

Abstract Understanding how different environmental factors influence species occurrence is a key issue to address the study of natural populations. However, there is a lack of knowledge on how local traits influence the microhabitat use of tropical arboreal lizards. Here, we investigated the microhabitat selection of the poorly known lizard Tropidurus lagunablanca (Squamata: Tropiduridae) and evaluated how environmental microhabitat features influence animals presence. We used a Resource Selection Function approach, in a case/control design where we analyzed the effect of substrate temperature and trees diameter at breast height (DBH) in the probability of presence of lizards using mixed Conditional Logistic Regression. We found that T. lagunablanca uses trees with DBH from 0.40 m to 4 m and substrate temperatures ranging from 25.9°C to 42°C. Moreover, we showed that thickness of the trees and substrate temperatures significantly increased the probability of presence of T. lagunablanca individuals, being the probability of presence higher than 50% for trees up to 1.5 m DBH and temperature of substrate up to 37.5°C. Our study probed that T. lagunablanca individuals choose trees non-randomly, selecting thicker and warmer tree trunks. This information advances the knowledge of the spatial ecology of Neotropical arboreal lizards and is relevant for conservation, putting an emphasis on preserving native vegetation in the Pantanal.

RESUMO

In this study, we report the temporal occurrence and habitat and microhabitat use by anurans in two areas located in one highland marsh (brejo-de-altitude) in northeastern Brazil. Fieldwork was carried out between September 2011 and September 2012. The recorded anurans belong to 14 species distributed in five families: Hylidae (six), Leptodactylidae (five), Bufonidae, Odontophrynidae and Pipidae (one each). Vocalization activity was seasonal and concentrated in the wetter and warmer months, but correlated to rainfall only in the top in the Chapada do Araripe. Richness and abundance of calling anurans were lower in the humid forest of the slope than in Cerradão area in the top of the Chapada do Araripe. Scinax x-signatus vocalized during nine months, and along with Dendropsophus soaresi, Phyllomedusa nordestina and Physalaemus cuvieri presented the longest periods of vocalization with the highest number of species vocalizing in at the height of the rainy season. Males were recorded vocalizing in nine different microhabitats, Adenomera sp. uses leaf litter and P. cuvieri the edge of water bodies as calling site both two sampled areas. Differences in richness and abundance of anurans between the two habitats are probably due to physical characteristics, such as presence of lentic environments.

Neste estudo são descritas a ocorrência temporal e o uso de habitat e microhabitat dos anuros de duas localidades em uma área de brejo de altitude no nordeste do Brasil. As amostragens foram realizadas entre setembro de 2011 e setembro de 2012. Foram registrados anuros pertencentes a 14 espécies distribuídas em cinco famílias: Hylidae (seis), Leptodactylidae (cinco), Bufonidae, Odontophrynidae e Pipidae (uma cada). A atividade de vocalização foi sazonal e concentrada nos meses mais úmidos e quentes, mas correlacionada somente com as chuvas no topo da Chapada do Araripe. A riqueza e abundância de anuros vocalizando foram menores na floresta úmida da encosta que na área de Cerradão do topo da Chapada do Araripe. Scinax x-signatus vocalizou durante nove meses, e juntamente com Dendropsophus minutus, D. soaresi, Phyllomedusa nordestina e Physalaemus cuvieri apresentou os períodos de vocalização mais prolongados, com maior abundancia de indivíduos vocalizando no ápice do período chuvoso. Machos de anuros foram registrados vocalizando em nove microhabitats diferentes, Adenomera sp. utiliza serrapilheira e P. cuvieri a margem dos corpos d'água como sítios de vocalização em ambas áreas amostradas. Diferenças na riqueza e abundância de anuros entre os dois habitats estudados estão associadas ès características estruturais dos mesmos, como a presença de ambientes lênticos.

RESUMO

Vegetation structure and floristics have a strong influence on the relative abundance of spider guilds and functional diversity of terrestrial arthropods. Human activities have transformed much of the temperate woodlands. The aim of this study was to test five predictions related to the guild distribution and functional diversity of the ground spider communities of Eucalyptus plantations and native pine woodlands in western Mexico. Spiders were collected every fortnight from September to November from 15 pitfalls positioned in each of the eight sites. We also assessed the cover of grasses, herbs, shrubs, and leaf litter in each site. We found that the abundances of ground hunters and sheet weavers between plantations and pine woodlands were different. Nevertheless, there was not a consistent difference between sites of each of the vegetation types. Most species of ground hunters, sheet web weavers, and many other hunters were associated with litter and the grass cover. Nonetheless, in some cases, species of different families belonging to the same guild responded to different variables. Wolf spiders were related to the grass Aristida stricta Micheaux, 1803, while the species of the other families of ground hunters were associated with leaf litter. One Eucalyptus plantation and one pine woodland had the highest functional diversity of all sites. These sites have a well developed litter and grass cover. Our study suggests that the abundance of litter and a high cover of grasses explain the occurrence of species with different traits, and these habitat components results in a high functional diversity.

Assuntos

RESUMO

Anolis auratus is a widely distributed species, from Costa Rica in Central America, through northern South America, including Colombia, Venezuela, northern Brazil, Surinam and the Guyanas. In Colombia, its widespread distribution across different life zones suggests that these lizards occupy different environments and exhibit different microhabitat use in different geographic areas. On the other hand, some observations suggest that this species prefers open areas, selecting grasslands over brushy areas, and thus, an alternative hypothesis is that microhabitat use is similar among different populations. In Anolis, body variables related to locomotion (body size and shape) define structural microhabitat use, so two distinct patterns could be expected in this species: conservative or highly variable body size and shape throughout the species distribution. To test these predictions, we characterized geographic variation in morphometric traits of this species in Colombia. Females and males were similar in body size, but exhibited differences in some variables related to body shape. These characteristics also varied among males and females from different regions, suggesting heterogeneous use of structural microhabitat, between sexes and among populations. As an alternative, phylogenetic divergence among populations could also account for the observed differences. Absence of ecological and phylogenetic data limits our ability to identify the underlying causes of this pattern. However, we provide a general framework to explore hypotheses about evolution of body size and shape in this species.

Anolis auratus se distribuye desde Costa Rica en Centro América, el norte de Sur América, incluyendo Colombia, Venezuela, norte de Brasil, Surinam y las Guyanas. En Colombia, su amplia distribución en distintas zonas de vida sugiere que estos lagartos ocupan distintos ambientes, y por tanto, posiblemente exhiben variación geográfica en el uso de microhabitat. Por otra parte, algunas observaciones sugieren que estos lagartos prefieren zonas abiertas, seleccionando pastizales y por tanto, una hipótesis alternativa es que usan el mismo microhabitat en toda su distribución. En Anolis, las variables corporales relacionadas con el movimiento (tamaño y forma corporal) definen el uso del microhabitat, así que pueden esperarse dos patrones en esta especie: tamaño y forma corporal conservativos o altamente variables a lo largo de su distribución. Caracterizamos la variación geográfica en variables morfométricas de esta especie en Colombia. Hembras y machos mostraron tamaño corporal similar, pero fueron distintos en la forma del cuerpo. La forma corporal varía también en machos y hembras de distintas regiones, sugiriendo un uso heterogéneo del microhabitat estructural. Como alternativa, la divergencia filogenética entre poblaciones podría explicar las diferencias observadas. La ausencia de datos ecológicos y filogenéticos para la especie limita las hipótesis sobre causas de este patrón. Proveemos un marco general para explorar hipótesis que expliquen la evolución de tamaño y forma corporal en esta especie.

RESUMO

Composition, species diversity and resource usage in terms of space and time were evaluated for the lizard community of the Ecological Station of the Seridó (ESEC Seridó), Rio Grande do Norte. An observation area of 150 m × 150 m (2.25 ha) was delimited and surveyed monthly in alternate turns (morning, afternoon and night) for three consecutive days from April to October 2011, covering dry and rainy seasons. Fourteen species belonging to eight families were recorded, being Tropidurus semitaeniatus the most abundant. Seasonality influenced species richness and abundance. Regarding habitat usage, Lygodactylus klugei was the most generalist species, while Phyllopezus periosus, P. pollicaris and T. semitaeniatus were specialists, showing affinity for rocky formations. About microhabitat usage, the most generalist species was T. hispidus and the most specialized was L. klugei . Ten of the recorded species have diurnal habits and four are nocturnal. The space and time usage profiles of the dominant species corroborated data obtained in previous autoecological studies conducted in the same area and suggest a pattern of resource usage by these species in the ESEC Seridó.

Neste trabalho foram avaliadas a composição, diversidade de espécies e a utilização dos recursos espaço e tempo na comunidade de lagartos da Estação Ecológica do Seridó (ESEC Seridó), Rio Grande do Norte. Para isso, uma área de observação de 150m × 150m (2,25 ha) foi delimitada e percorrida mensalmente em turnos alternados (manhã, tarde e noite) por três dias consecutivos nos meses de abril a outubro de 2011, cobrindo as estações seca e chuvosa. Foram registradas 14 espécies pertencentes a oito famílias, dentre as quais a mais abundante foi Tropidurus semitaeniatus. A sazonalidade influenciou a riqueza e abundância das espécies. Quanto ao uso do hábitat, Lygodactylus klugei foi a espécie mais generalista, enquanto Phylopezus periosus, P. pollicaris e T. semitaeniatus demonstraram especialidade às áreas de formações rochosas. Quanto ao uso de microhábitats, a espécie mais generalista foi T. hispidus e a mais especialista foi L. klugei. Dez das espécies registradas possuem hábito diurno e quatro são noturnas. Os perfis de uso do espaço e do tempo pelas espécies dominantes corroboram dados obtidos em estudos anteriores nesta mesma área e sugerem a existência de padrões na utilização desses recursos por estas espécies na ESEC Seridó.

RESUMO

Studies on the natural history of the lizard Enyalius iheringii Boulenger, 1885, as well as other tropical lizards, are rare. In this study, some aspects of the natural history of this endemic species from the Atlantic forest are reported in areas of Vale do Itajaí, state of Santa Catarina, Brazil. Twenty individuals were found, of which 18 were collected. Most of them were found over the vegetation (n=17) and on the ground (n=3). The main defensive strategy displayed was camouflage (n=16). Jumping (n=1), jumping and running (n=1) and running (n=2) were also observed in some individuals. When handled, lizards exhibited mouth wide open, hissing, and occasionally biting, as well as color change in males. Regarding its diet, the numerically most important prey was beetles (Coleoptera), followed by Lepidoptera larvae. Beetles, lepidopteran larvae and spiders were the most frequent food items. Males and females did not differ in size. Three sexually mature females (100-113 mm SVL) were found in December and January.

Informações sobre a história natural do lagarto Enyalius iheringii Boulenger, 1885 são escassas, assim como para várias espécies de lagartos de florestas tropicais. Neste estudo abordamos vários aspectos da história natural desta espécie endêmica da Mata Atlântica, na região do Vale do Itajaí, Santa Catarina. Encontramos 20 indivíduos, dos quais 18 foram coletados. A maioria foi encontrada sobre a vegetação (n=17) e o restante sobre o solo (n=3). A camuflagem foi a principal tática defensiva utilizada (n=16), apesar de também observarmos salto (n=1), salto e corrida (n=1) e corrida (n=2). Quando manipulados, apresentaram o comportamento de escancarar a boca, emissão de silvos e eventualmente mordidas, assim como mudança de coloração em machos. Com relação à dieta, as presas mais consumidas foram coleópteros, seguidos por larvas de lepidópteros; em relação à frequência, os itens mais representativos foram coleópteros, seguidos por larvas de lepidópteros e aranhas. Machos e fêmeas não diferiram em relação ao tamanho do corpo. Três fêmeas reprodutivas (100-113 mm CRC) foram encontradas nos meses de dezembro e janeiro.

RESUMO

Studies on the natural history of the lizard Enyalius iheringii Boulenger, 1885, as well as other tropical lizards, are rare. In this study, some aspects of the natural history of this endemic species from the Atlantic forest are reported in areas of Vale do Itajaí, state of Santa Catarina, Brazil. Twenty individuals were found, of which 18 were collected. Most of them were found over the vegetation (n=17) and on the ground (n=3). The main defensive strategy displayed was camouflage (n=16). Jumping (n=1), jumping and running (n=1) and running (n=2) were also observed in some individuals. When handled, lizards exhibited mouth wide open, hissing, and occasionally biting, as well as color change in males. Regarding its diet, the numerically most important prey was beetles (Coleoptera), followed by Lepidoptera larvae. Beetles, lepidopteran larvae and spiders were the most frequent food items. Males and females did not differ in size. Three sexually mature females (100-113 mm SVL) were found in December and January.

Informações sobre a história natural do lagarto Enyalius iheringii Boulenger, 1885 são escassas, assim como para várias espécies de lagartos de florestas tropicais. Neste estudo abordamos vários aspectos da história natural desta espécie endêmica da Mata Atlântica, na região do Vale do Itajaí, Santa Catarina. Encontramos 20 indivíduos, dos quais 18 foram coletados. A maioria foi encontrada sobre a vegetação (n=17) e o restante sobre o solo (n=3). A camuflagem foi a principal tática defensiva utilizada (n=16), apesar de também observarmos salto (n=1), salto e corrida (n=1) e corrida (n=2). Quando manipulados, apresentaram o comportamento de escancarar a boca, emissão de silvos e eventualmente mordidas, assim como mudança de coloração em machos. Com relação à dieta, as presas mais consumidas foram coleópteros, seguidos por larvas de lepidópteros; em relação à frequência, os itens mais representativos foram coleópteros, seguidos por larvas de lepidópteros e aranhas. Machos e fêmeas não diferiram em relação ao tamanho do corpo. Três fêmeas reprodutivas (100-113 mm CRC) foram encontradas nos meses de dezembro e janeiro.

RESUMO

The activity pattern of the small sand lizard, Liolaemus occipitalis Boulenger, 1885, was investigated in the coastal sand dunes at Quintão beach (Palmares do Sul, southern, Brazil), between September 1998 and August 1999. The results showed that L. occipitalis is active all along the year, but with variations in its daily and seasonal activity patterns associated to climatic changes in the habitat. Lizard activity pattern was distributed as follows: under the sand, burrowed (73%), under vegetation (14%), dislocation (7%) and basking (6%). Mean habitat temperatures (air and substrate) were significantly different. The results indicate that L. occipitalis is a thigmothermic and heliothermic species that regulates its body temperature through behavioral mechanisms, and that thermoregulation is mainly associated with substrate.

Este trabalho teve por objetivo o estudo da atividade anual do lagarto Liolaemus occipitalis Boulenger, 1885. O estudo se desenvolveu nas dunas costeiras da praia de Quintão (Palmares do Sul, sul do Brasil), no período de setembro de 1998 a agosto de 1999. Os resultados demonstraram que L. occipitalis é ativo ao longo de todo o ano com variações diárias e sazonais de acordo com as mudanças climáticas do habitat. A atividade do lagarto se distribuiu da seguinte forma: sob a areia (73%), sob a vegetação (14%), deslocando-se (7%) e exposto ao sol (6%). As temperaturas medias do hábitat (ar e substrato) diferiram significativamente. Os resultados indicaram que L. occipitalis é tigmotérmico e heliotérmico, regulando a sua temperatura corporal através de mecanismos comportamentais, estando a mesma relacionada principalmente com a temperatura do substrato.

RESUMO

The activity pattern of the small sand lizard, Liolaemus occipitalis Boulenger, 1885, was investigated in the coastal sand dunes at Quintão beach (Palmares do Sul, southern, Brazil), between September 1998 and August 1999. The results showed that L. occipitalis is active all along the year, but with variations in its daily and seasonal activity patterns associated to climatic changes in the habitat. Lizard activity pattern was distributed as follows: under the sand, burrowed (73%), under vegetation (14%), dislocation (7%) and basking (6%). Mean habitat temperatures (air and substrate) were significantly different. The results indicate that L. occipitalis is a thigmothermic and heliothermic species that regulates its body temperature through behavioral mechanisms, and that thermoregulation is mainly associated with substrate.

Este trabalho teve por objetivo o estudo da atividade anual do lagarto Liolaemus occipitalis Boulenger, 1885. O estudo se desenvolveu nas dunas costeiras da praia de Quintão (Palmares do Sul, sul do Brasil), no período de setembro de 1998 a agosto de 1999. Os resultados demonstraram que L. occipitalis é ativo ao longo de todo o ano com variações diárias e sazonais de acordo com as mudanças climáticas do habitat. A atividade do lagarto se distribuiu da seguinte forma: sob a areia (73%), sob a vegetação (14%), deslocando-se (7%) e exposto ao sol (6%). As temperaturas medias do hábitat (ar e substrato) diferiram significativamente. Os resultados indicaram que L. occipitalis é tigmotérmico e heliotérmico, regulando a sua temperatura corporal através de mecanismos comportamentais, estando a mesma relacionada principalmente com a temperatura do substrato.

RESUMO

En este estudio registramos el uso de sitios para dormir por Anolis "anoriensis" y Anolis mariarum en un bosque montano al norte de la Cordillera Central de Colombia, con el objetivo de examinar la ocurrencia de segregación espacial entre ellas. Además, estimamos la disponibilidad de perchas en ambos sitios. Anolis mariarum durmió con mayor frecuencia en arbustos (51%) que en otros tipos de perchas (arboles, helechos, herbáceas), y lo hizo en proporción similar a su disponibilidad. Anolis "anoriensis" utilizó de manera diferencial los tipos de percha en los dos sitios muestreados, dependiendo de la presencia/ausencia de la otra especie. Esta variación en la selección de los arbustos por A. "anoriensis" sugiere la existencia de competencia entre ambas especies cuando ocurren sintópicamente.

In this study we recorded the use of sleeping site by Anolis "anoriensis" and Anolis mariarum in two study sites located in the montane forest of the extreme northern of Cordillera Central, Colombia. We also tested the occurrence of spatial segregation between the two species. Furthermore, we estimated perch availability in both study sites. Anolis mariarum slept more frequently on shrubs (51%) than other kinds of perches (ferns, herbs, trees), but did so in proportion to their availability. Anolis "anoriensis" used different kinds of perches in each site, depending on the presence/absence of A. mariarum. Such variation in response to shrubs as sleeping perches by A. "anoriensis" suggests the existence of competition between the species when they are in syntopy.

RESUMO

En este estudio registramos el uso de sitios para dormir por Anolis "anoriensis" y Anolis mariarum en un bosque montano al norte de la Cordillera Central de Colombia, con el objetivo de examinar la ocurrencia de segregación espacial entre ellas. Además, estimamos la disponibilidad de perchas en ambos sitios. Anolis mariarum durmió con mayor frecuencia en arbustos (51%) que en otros tipos de perchas (arboles, helechos, herbáceas), y lo hizo en proporción similar a su disponibilidad. Anolis "anoriensis" utilizó de manera diferencial los tipos de percha en los dos sitios muestreados, dependiendo de la presencia/ausencia de la otra especie. Esta variación en la selección de los arbustos por A. "anoriensis" sugiere la existencia de competencia entre ambas especies cuando ocurren sintópicamente.

In this study we recorded the use of sleeping site by Anolis "anoriensis" and Anolis mariarum in two study sites located in the montane forest of the extreme northern of Cordillera Central, Colombia. We also tested the occurrence of spatial segregation between the two species. Furthermore, we estimated perch availability in both study sites. Anolis mariarum slept more frequently on shrubs (51%) than other kinds of perches (ferns, herbs, trees), but did so in proportion to their availability. Anolis "anoriensis" used different kinds of perches in each site, depending on the presence/absence of A. mariarum. Such variation in response to shrubs as sleeping perches by A. "anoriensis" suggests the existence of competition between the species when they are in syntopy.