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The mara Dolichotis patagonum (Caviomorpha, Caviidae) is probably the extant rodent with the most pronounced postcranial specializations for fast locomotion. When running the species can reach a speed of ~40 km/h. It has been suggested that its body posture and limb bones show evolutionary parallelism regarding small-sized artiodactyl species. Due to its elongated limbs and relatively large body mass (average 8 kg) compared to other rodents, its limb bones may experi-ence large loads at high speeds. Using kinematic data from high speed video films and skeletal dimensions of museum specimens, ground reaction forces and stresses acting on the humerus and tibia during different gaits were estimated. Values of bending stress obtained for the tibia were greater than those for the humerus during walking, gallop and “pronk”. The stress experienced by the tibia when running doubled the value obtained when walking (54.5 vs. 26.1 MPa, respec-tively). Estimated bone safety factors were less than half during fast locomotion (3.1) compared to walking (6.4). It is discussed how maras’ body posture and skeletal dimensions affect bone stress experienced during locomotion. Fil: Vassallo, Aldo Iván. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentina Fil: Rocha Barbosa, Oscar. Universidade do Estado de Rio do Janeiro; Brasil

Mandibles from separate populations of free-living mouflons (Ovis aries musimon) from Southern Spain, submitted to different ecological conditions, were studied. Searching for ontogenetic shape variations we used geometric morphometrics tools and we explored the use of several mathematical models for describing growth rate variations between populations and sexes. A strong allometry was detected with variations in shape mainly matching with molar and premolar eruption. Mandible shape did not vary significantly with sex nor was sexual size dimorphism detected in adults, whatever the population. By modeling growth we detected differences between populations in all parameters such as the maturity rate describing precocity, and the time it took to reach asymptotic size (varying from 9 up to 18 months). A longer period of growth did not result in a larger asymptotic size, but it led to smaller mandibles. Mouflons with relatively late teeth replacement, lower maturation rate and smaller adult size were those of the population submitted to extreme environmental conditions, like epizootic disease, droughts and ungulate overpopulations. We discuss how a delay in reaching mature size has probably an important subsequent impact on reproductive and life-history traits in this species. Being able to record the effects of density-dependent and density-independent factors, mandibles become a target of interest for ecological and management studies also on mouflons.

The origin and distribution of the femoral nerves in both antimeres were studied in 30 New Zealand rabbits (15 males and 15 females). The specimens were collected after natural death and fixed with 10% formaldehyde solution. In males, the femoral nerve originated from the ventral branches of the fourth, sixth and seventh lumbar spinal nerves in seven animals (46.67%), in two animals (13.33%) from the ventral branches of the fifth and sixth lumbar spinal nerves, in one animal (6.67%) from the ventral branch of the fifth lumbar spinal nerve, in three animals (20%) from the ventral branches of the fifth, sixth and seventh lumbar spinal nerves, in one animal (6.67%) from the ventral branches of the fourth and fifth lumbar spinal nerves, and in one animal (6.67%) from the ventral branches of the fifth and seventh lumbar spinal nerves. In females, the femoral nerve originated from the ventral branches of the fourth, sixth and seventh lumbar spinal nerves in four animals (26.67%), in two cases (13.33%) from the ventral branches of the fifth and sixth lumbar spinal nerves, in one animal (6.67%) from the ventral branch of the fifth lumbar spinal nerve, in three animals (20%) from the ventral branches of the sixth and seventh lumbar spinal nerves, in four animals (26.67%) from the ventral branches of the fifth, sixth and seventh lumbar spinal nerves and in one animal (6.67%) from the ventral branches of the fourth and seventhlumbar spinal nerves. In all animals the femoral nerves were distributed in different branches to the major and minor psoas, femoral quadriceps, sartorius and pectinius muscles. Se estudió el origen y distribución del nervio femoral de ambos antímeros en 30 conejos neozelandeses, 15 machos y 15 hembras. Los animales fueron recolectados después de su muerte natural y se fijaron en formaldehído al 10%. En los machos, el nervio femoral se originó a partir de los ramos ventrales del cuarto, sexto y séptimo nervios espinales lumbares en siete casos (46,67%); en tres casos (20%) desde los ramos ventrales del quinto, sexto y séptimo nervios espinales lumbares; en dos casos (13,33%) desde los ramos ventrales del quinto y sexto nervios espinales lumbares, mientras que en tres animales (n=1 respectivamente), desde los ramos ventrales del quinto nervio espinal lumbar (6,67%), los ramos ventrales del cuarto y quinto nervios lumbares espinales (6,67%) y desde los ramos ventrales del quinto y séptimo nervios espinales lumbares. En las hembras, el nervio femoral se originó a partir de los ramos ventrales del cuarto, sexto y séptimo nervios espinales en cuatro casos (26,67%); en otros cuatro casos (26,67%) desde los ramos ventrales del quinto, sexto y séptimo nervios espinales lumbar, en tres casos (20%) desde los ramos ventrales del sexto y séptimo nervios espinales lumbares, en dos casos (13,33%) desde los ramos ventrales del quinto y sexto nervios espinales, y en dos animales (n=1, respectivamente) procedían desde los ramos ventrales del quinto nervio espinal lumbar (6,67%) y de los ramos ventrales del cuarto y séptimo nervios espinales lumbares (6,67%). Los nervios femorales en todos los animales estaban distribuidos en diversos ramos de los músculos psoas mayor y menor, cuádriceps femoral sartorios y pectinatos.

Here we report the first record of Drymoreo­mys albimaculatus Percequillo, Weksler & Costa, 2011 (Cricetidae, Sigmodontinae) in Rio de Janeiro state, Brazil. One specimen was captured at Serra da Bocaina National Park, municipality of Paraty. The specimen was captured in a pitfall trap, in a mixed habitat of forest and bamboo. The karyotype showed 2n = 62 and FN = 62, which is similar to the previously described for the species.

Morphological variation of the ramus mandibulae of wild Sus scrofa was described and correlated to sex and age differences. Young forms (n=27, 15 males, 12 females) and adults (n=23, 13 males, 10 females) were analyzed through Geometric Morphometrics (2-D) to assess differences between groups. We found significant differences between age- and sex-related shape variations at ramus mandibulae level. Young wild boars present bulky angular process with backward oriented coronoid process, while adults show slender jaw vertical ramus, and orthogonally oriented coronoid process. The ramus mandibulae in female wild boars is more robust and bulky than in males. The morphological changes between young and adult forms are related to alterations in the osteo-muscular jaw complex along wild boars ontogeny. The jaw morphological variations observed in adult wild boars could also be related to dietary differences between sexes. Se describen las variaciones morfológicas a nivel de la rama mandibular del jabali (Sus scrofa) en función del sexo y la edad. Se analizó material procedente de jabalíes juveniles (n=27, 15 machos y 12 hembras) y adultos (n=23, 13 machos y 10 hembras) a través de la morfometría geométrica (2-D) para valorar diferencias entre grupos. Se encontraron diferencias a nivel de la forma del ángulo mandibular entre edades y sexos, de manera que los individuos juveniles presentaron un ángulo más abultado y un proceso coronoides orientado hacia atrás, mientras que los adultos muestran una rama mandibular más estrecha y vertical, así como, un proceso coronoides orientado ortogonalmente. En las hembras la parte posterior de la mandíbula es más abultada y compacta que en los machos. Los cambios morfológicos entre juveniles y adultos están relacionados con los procesos ontogenéticos que afectan al complejo osteomuscular durante el crecimiento. Por otra parte, las variaciones morfológicas observadas en los adultos podrían tener relación con diferencias en la dieta entre ambos sexos.

The intestines of Sturnira lilium, Phyllostomus hastatus, Carolliaperspicillata, GlossophagasoricinaíindDesmodus rotundus were analized through macroscopic, morphometric and light microscopy studies. The species studied presented some common charactenstics generally found in bats, such as the absence of a caecum and an appendix. The frugivorous bat S. lilium has a longer intestine than the other species. The intestinal epithelium is of the simple columnar type, constituted of absorptive cells characterized by microvilli and goblet cells, which in all the species proved to be PAS + and AB +. These cells presented some differences in quantity and in distribution among the species. The intestinal mucosa presented morphologic and morphometric differences, such as the shape and size of villi as well as the length of the crypts of Lieberkühn. Histologically the different intestinal portions could be distinguished: in the middle portion we found few goblet cells and long villi; in the distal portion we found an increase in goblet cells and a decrease in villi height; and in the large intestine no villi were found, but rather abundant intestinal glands with numerous goblet cells. In C. perspicillata, P. hastatus and G. soricina we could observe Peyeras patches in the distal portion near the large intestine, whereas in D. rotundus and S. lilium we found aggregations of lymphoid nodulous tissue distributed along the tube. In all species we observed the presence of Paneth cells at the base of the crypts of Lieberkühn. We could observe differences among the species in the distribution of collagen in the small intestine submucosa and serosa. The outer muscular layer has one circular layer and a longitudinal layer, the circular layer increasing in thickness along the tube. Large intestine charactenstics are uniform among the species. Sfractures such as the taenia coli and the appendices epiploicae were absent. These results should contribute not only to improve understanding of bat morphology, but also to provide grounds for the evaluation of evolutionary models on the adaptive radiation of phyllostomid feeding habits. Los intestinos de Sturnira azucenas, Phyllostomus hastatus, Carollia perspicillata, Glossophaga soricina y Desmodus rotundus se analizaron a través de estudios macroscópicos, morfométricos y de microscopía de luz. Las especies estudiadas presentan algunas características comunes en general encontradas en murciélagos, tales como la ausencia de un ciego y un apéndice. Murciélagos frugívoros S. azucenas tienen un intestino más largo que el de otras especies. El epitelio intestinal es de tipo columnar simple, constituido por células de absorción que se caracterizan por microveilosidades y células caliciformes, que en todas las especies resultó ser PAS + y AB +. Estas células presentan algunas diferencias en cantidad y en la distribución entre las especies. La mucosa intestinal presenta diferencias morfológicas y morfométricas, como la forma y el tamaño de las vellosidades, así como la longitud de las criptas de Lieberkühn. Histológicamente las diferentes partes intestinales pueden ser distinguidas: en la parte media encontramos pocas células caliciformes y largas vellosidades, en la porción distal encontramos un aumento de células caliciformes y una disminución en la altura de vellosidades, y en el intestino grueso no se encontraron vellosidades, sino más bien abundantes glándulas intestinales con numerosas células caliciformes. En C. perspicillata, P hastatus y G. soricina podemos observar placas de Peyer en la porción distal, cerca del intestino grueso, mientras que en D. rotundus y S. azucenas se encontraron agrupaciones de tejido linfoide nodular distribuido a lo largo del tubo. En todas las especies se observó la presencia de células Paneth en la base de las criptas de Lieberkühn. Hemos podido observar diferencias entre las especies en la distribución de colágeno en el intestino delgado y submucosa serosa. La capa muscular exterior tiene una capa circular y una capa longitudinal, la capa circular en el aumento de espesor a lo largo del tubo. Las características del intestino grueso son uniformes entre las especies. Estructuras como la taenia coli y los apéndices epiploicos estuvieron ausentes. Estos resultados deben contribuir no sólo a mejorar la comprensión de la morfología del murciélago, sino también para sentar las bases para la evaluación de los modelos evolutivos adaptativa de la radiación en los hábitos alimenticios de filostómidos.

The intestines of Sturnira lilium, Phyllostomus hastatus, Carolliaperspicillata, GlossophagasoricinaíindDesmodus rotundus were analized through macroscopic, morphometric and light microscopy studies. The species studied presented some common charactenstics generally found in bats, such as the absence of a caecum and an appendix. The frugivorous bat S. lilium has a longer intestine than the other species. The intestinal epithelium is of the simple columnar type, constituted of absorptive cells characterized by microvilli and goblet cells, which in all the species proved to be PAS + and AB +. These cells presented some differences in quantity and in distribution among the species. The intestinal mucosa presented morphologic and morphometric differences, such as the shape and size of villi as well as the length of the crypts of Lieberkühn. Histologically the different intestinal portions could be distinguished: in the middle portion we found few goblet cells and long villi; in the distal portion we found an increase in goblet cells and a decrease in villi height; and in the large intestine no villi were found, but rather abundant intestinal glands with numerous goblet cells. In C. perspicillata, P. hastatus and G. soricina we could observe Peyeras patches in the distal portion near the large intestine, whereas in D. rotundus and S. lilium we found aggregations of lymphoid nodulous tissue distributed along the tube. In all species we observed the presence of Paneth cells at the base of the crypts of Lieberkühn. We could observe differences among the species in the distribution of collagen in the small intestine submucosa and serosa. The outer muscular layer has one circular layer and a longitudinal layer, the circular layer increasing in thickness along the tube. Large intestine charactenstics are uniform among the species. Sfractures such as the taenia coli and the appendices epiploicae were absent. These results should contribute not only to improve understanding of bat morphology, but also to provide grounds for the evaluation of evolutionary models on the adaptive radiation of phyllostomid feeding habits.

The excavatory movements of the spade-snouted amphisbaenid Leposternon microcephalum (Reptilia, Squamata) was studied with the aid of videofluorscopy (X-ray) techniques. This allows the observation of skull and column movements along tunneling, and a more detailed motion observation, being so a novel approach for amphisbaenian excavatory rescarches. A single specimen of Leposternon microcephalum was kept in a glass terrarium filled with semoline, and filmed with a scopy (X-ray) machine. Fixed anatomical marks on the head of the specimen were put in drawings from the framed recordings. Selected sequences of the recordings were fragmented in isolated frames for motion observation. The analysis of the recordings revealed a repetitive pattern of excavatory cycles, with retreating and downward bending of the head before its upstroke to compact the substrate tunnel roof. Follows a dropping of the head, which lays over the substrate giving support for the next retreating and downward head bending. This is an essential step that was neglected in earlier cycle descriptions. The initial downward head bending was not previously properly described for spade-snouted amphisbaenians. The excavatory movements of spade-snouted amphisbaenians are usually treated as a two-stepped cycle, but the evidence that this excavatory cycle has three steps is given here. Los movimientos excavatorios de la Amphisbaenia (culebrilla ciega), con hocico en forma de pala, Leposternon microcephalum (Reptilia: Squamata) se estudiaron con la ayuda de técnicas de videofluoroscopía (rayos X). Esto permite la observación de los movimientos del cráneo y columna, a lo largo de túneles, y una propuesta más detallada, siendo un enfoque novedoso para investigaciones de la culebrilla ciega excavadora. Un solo espécimen de Leposternon microcephalum se mantuvo en un terrario de vidrio lleno de semolina, y fue filmado con una máquina de escopía (rayos X). Se fijaron marcas anatómicas en la cabeza de éste y luego fueron dibujadas desde las grabaciones. Las secuencias seleccionadas de las grabaciones fueron fragmentadas en fotogramas aislados de la observación del movimiento. Los análisis de las grabaciones revelaron un patrón repetitivo de ciclos excavatorios, con la retirada y doblamiento hacia abajo de la cabeza, antes de su movimiento hacia arriba para compactar el sustrato del techo del túnel. Sigue una caida de la cabeza, que se pone sobre el apoyo del sustrato para la próxima retirada y doblamiento hacia abajo de la cabeza. Esto es un paso esencial que es descuidado en las descripciones anteriores del ciclo. La primera flexión baja de la cabeza no fue debidamente descrita anteriormente para Amphisbaenia con hocico en forma de pala. Los movimientos excavatorios de estos animales suelen ser tratados como un período de dos ciclos intensificados, pero la evidencia que este ciclo excavatorio consta de tres pasos, se dan aquí.

Imantodes cenchoa (Duméril, 1853) is an arboreal, nocturnal and oviparous xenodontine snake, which feeds on amphibians and lizards. It is found in Central and South America, including northern and central Brazil. In this work, we investigated the relationship between topographic anatomy and habitat in I. cenchoa. Twenty specimens (13 non pregnant females and 7 males) were examined. The topographic anatomy study was realized through observations of the internal anatomy, particularly the position and size of lung, heart, liver, left and right gonads and left and right kidneys. Results showed that all the organs are located in a posterior position in relation to the snout vent length (SVL). The centre of gravity is found at about 74% of SVL in both males and females. In males, no positive allometry was observed among the positions of the organs. Negative allometry in females was observed regarding the position of the anterior tip of the left kidney, the anterior and posterior tips of the right kidney and in both ovaries. In males, negative allometry is present in the position of all the organs. The distance between the last follicle and the cloaca was 8.78% of SVL. Our data corroborate the idea that the posterior position of all internal organs is linked to a habitat specialization of a snake, linking the arboreal species I. cenchoa with a relatively posterior internal topography Imantodes cenchoa (Duméril, 1853) es una serpiente xenodontinea, arbórea, noctura y ovípara, que se alimenta de anfibios y largartos. Se encuenta en América Central y del Sur, incluyendo las partes Norte y Central de Brasil. En este trabajo, investigamos la relaciones entre la Anatomía Topográfica y hábitat en I. cenchoa. Fueron examinados 20 especímenes (13 hembras no preñadas y 7 machos). El estudio de la Anatomía Topográfica fue realizada a través de observaciones de la anatomía interna, particularmente la posición y tamaño del pulmón, corazón, hígado, gónadas y riñones derechos e izquierdos. Los resultados mostraron que todos los órganos están localizados en una posición posterior, en relación a la entrada de la longitud del hocico(SVL). El centro de gravedad se encuentra a 74% de SVL en machos y hembras. En los machos, no fue observada alometría positiva entre la posición de los órganos. Fue observada alometría negativa en las hembras, considerando la posición del extremo anterior del riñón izquierdo, los extremos anterior y posterior del riñón derecho y ambos ovarios. En machos, se presentó alometría negativa en la posición de todos los órganos. La distancia entre el último folículo y la cloaca fue 8.78% de SVL. Nuestros datos corroboran la idea que la posición posterior de todos los órganos internos está marcada por una especialización al hábitat de una serpiente, marcando la especie arbórea I. cenchoa con una especial topografía interna posterior

Tijubina pontei is a basal lizard found in the Crato Member, Santana Formation, Lower Cretaceous (Aptian), Brazil. It is considered a sister group of Huehuecuetzpalli mixtetus, the only basal lizard previously known, found in Mexico. The paleoautoecology of T. pontei is compatible with a terrestrial animal, omnivorous, which could eventually occupy other ecological niches. Based on their dentition and ecomorphology, their behaviour could be a combination of active forager or a "sit-and-wait" one. It could even perform bipedal locomotion. Comparing T. pontei with Liolaemus lutzae, an extant brazilian lizard, we find many characters and morphological similarities. This suggests that the L. lutzae habits could be extrapolated to the paleoenvironment of T. pontei which, probably, lived in a sandy habitat, with a vegetation that could support variations in salinity and high temperatures. Tijubina pontei é um lagarto basal encontrado no Membro Crato da Formação Santana, Cretáceo Inferior do Brasil (Aptiano), considerado grupo irmão de Huehuecuetzpalli mixtetus, até então o único lagarto basal conhecido, proveniente do México. A paleoautoecologia de T. pontei é compatível com a de um animal terrestre, onívoro que, eventualmente, pudesse ocupar outros nichos ecológicos. Baseado em sua dentição e ecomorfologia, seu comportamento poderia ser combinado, como forrageador ativo ou senta-espera, podendo apresentar bípedalismo. Comparando-se T. pontei com Liolaemus lutzae, lagarto atual do Brasil, encontramos muitos caracteres e inúmeras similaridades morfológicas entre ambos, sugerindo que os hábitos de L. lutzae, poderiam ser extrapolados para o paleoambiente de T. pontei que, provavelmente, vivia em um ambiente arenoso, praial, com uma vegetação que poderia suportar variações de salinidade e de altas temperaturas.

Tropidurus torquatus and Liolaemus lutzae, found in a restinga habitat, show some morphological differences associated with differential microhabitats use. There were made measurements of the snout-vent length, length and width of the largest toe of hand and foot, and length, width, height and curvature of the claws. We counted the number of adhesive lamellae of the largest toe of each member. T. torquatus has larger toes, greater number of adhesive lamellae and higher and more curve claws than L. lutzae. No significant differences in toe and claw widths were found. These results suggest that the differences found in the morphology of toes and claws of these two species would be associated with the differential microhabitat use. T. torquatus has morphological adaptations that allow it to use the microhabitat both vertically or horizontally, while L. lutzae use it only horizontally Tropidurus torquatus y Liolaemus lutzae hallados en un hábitat de restinga, muestran algunas diferencias morfológicas asociadas a el uso diferencial de microhábitats. Se realizaron mediciones de la longitud "snout-vent", longitud y ancho del dedo mayor de la mano y el pie y, longitud, ancho, altura y curvatura de las garras. Se contó el número de lamelas adhesivas del dedo mayor de cada miembro. T. torquatus posee dedos más grandes, mayor número de lamelas adhesivas y garras más altas y curvadas que L. lutzae. No se hallaron diferencias significativas en los anchos de dedos y garras. Estos resultados sugieren que las diferencias encontradas en la morfología de dedos y garras de estas dos especies estarían asociadas con el uso diferencial del microhábitat. T. torquatus posee adaptaciones que le permiten utilizar el microhábitat tanto vertical como horizontalmente, mientras que L. lutzae solamente lo utiliza en forma horizontal

The ungual phalanxes of recent crocodylomorphs are modified into queratin covered claws. They are conical, ventrally curved with a sharp distal end. They are used during locomotion, digging and female sizing on copula. Nevertheless, fossil crocodylomorphs claws present a wider morphological and functional diversity. It was analysed fossil claws from the Late Cretaceous rocks of Adamantina (General Salgado County) and Marília (Uberaba County) Formations of the Bauru Basin. The claws found in the Adamantina Formation were associated with skeletal remains of a baurusuchid. They are laterally compressed, more ventrally curved and stronger than those of recent crocodylomorphs. They also present, at their base, many furrows related to muscle attachment. The claws found in the Marília Formation were associated to the remains of a peirosaurid. They show a great lateral compression and a blade-like ventral edge. They also present a slight ventral curvature and strong furrows in their base for muscle attachment. The morphological data obtained from these claws allow the investigation of the autoecology of these Cretaceous crocodylomorphs. As falanges ungueais dos crocodilomorfos atuais são modificadas em garras cônicas, curvas ventralmente, com extremidade distal pontiaguda, recoberta por camadas de queratina. São utilizadas comoauxílio para tração durante o deslocamento, escavação e apreensão da fêmea durante a cópula. Entretanto, os crocodilomorfos fósseis apresentam maior diversidade morfológica e possivelmente funcional destas garras. Foram analisadas garras fósseis oriundas de rochas do Cretáceo Superior da Bacia Bauru, nas formações Adamantina (Município de General Salgado) e Marília (Município de Uberaba). As garras encontradas na Formação Adamantina estavam associadas a restos esqueléticos de um baurussuquídeo. Apresentam achatamento lateral, curvatura ventral intensa e robustez maior que a observada entre crocodilomorfos recentes, e várias estrias relacionadas aos ligamentos musculares na base da garra. As garras encontradas na Formação Marília estão associadas aos ossos de um peirossaurídeo. São robustas e intensamente comprimidas lateralmente; sua face ventral é comprimida e possui aspecto laminado. Apresentam pequena curvatura ventral e fortes estrias de fixação muscular em sua base. As características morfológicas destas garras podem auxiliar na investigação dos hábitos de vida destes crocodilomorfos cretácicos.

We studied some ecomorphological relationships in six lizard species (Ameiva ameiva, Cnemidophorus littoralis, Tropidurus torquatus, Liolaemus lutzae, Mabuya agilis and M. macrorhyncha) from Restinga de Barra de Maricá, RJ. These species have marked differences in microhabitat utilization and in foraging behavior, which vary from active to «sit-and-wait». In this study, we compared the morphology of the fingers and claws of these lizards species with the different behaviors. The species that showed higher degree of arboreality (T. torquatus and M. macrorhyncha) had the 4th finger of the forelimb as the largest, while the other species had the 3rd. This seems to give some advantage for vertical sustains of the arboreal species. All species had the 4th finger as the largest of the hind limb. The two scincids (M. agilis and M. macrorhyncha) had more curved and shorter claws, which appears to aid in the climbing on the leaves of the bromeliad Neoregelia cruenta. In addition, the claws of the essentially ground-dwelling species were larger than in the other species, suggesting that larger claws give some advantage for support on sand (providing a better impulse and speed), in the excavation of burrows, in the defense against predators, in the dispute for foraging ranges and in mate selection. In this study, the foraging strategy does not seem to be related to the absolute size of the fingers of the lizards, but with relative differences in the fingers of the forelimbs Estudiamos algunas relaciones ecomorfológicas en seis especies de lagartos (Ameiva ameiva, Cnemidophorus littoralis, Tropidurus torquatus, Liolaemus lutzae, Mabuya agilis y M. macrorhyncha) de la Restinga de la Barra de Maricá, RJ. Estas especies poseen marcadas diferencias en la utilización del microhabitat y en el comportamiento en la búsqueda de alimento, que varía de activo a «sienta-y-espera». Comparamos la morfología de los dedos y de las garras de especies de lagartos con estos comportamientos diferentes. Las especies que mostraron el grado más alto de arborealidad (T. torquatus e M. macrorhyncha) tenían el 4º dedo del miembro anterior como el más grande, y las otras especies tenían el 3º. Esto parece otorgarle una ventaja para la sustentación vertical de las especies arboreas. Todas las especies tenían el 4º dedo como el más grande del miembro posterior. Los dos scincídeos (M. agilis e M. macrorhyncha) tenían garras más cortas y curvas, que parecen ajudarle para la escalada de las hojas de la bromelia Neoregelia cruenta. Adicionalmente, las garras de las especies esencialmente terrícolas son mayores que las de otras especies, sugeriendo que garras mayores confieren un mejor apoyo en la arena (dándole mejor impulso y velocidad), en la excavación de escondrijos, en la defensa contra los predadores, en la disputa por sitios de alimentación y en la selección sexual. En el estudio, la estrategia de alimentarse no parece estar relacionada con el tamaño absoluto de los dedos de los lagartos, pero sí con las diferenciass relativas en los dedos de los miembros anteriores

Os lagartos do gênero Ophiodes, conhecidos popularmente como cobras-de-vidro, se caracterizam pelo corpo em formato serpentiforme, ausência de membros anteriores e membros posteriores rudimentares. Foram registrados em diferentes regiões do Brasil e em outros países da América do Sul. Apesar de suas peculiaridades morfológicas e grande distribuição geográfica, são raros os estudos conduzidos com espécies desse gênero. Este trabalho foi desenvolvido com o objetivo de contribuir para o conhecimento de aspectos morfológicos, reprodutivos, citogenéticos e locomotores de uma espécie do gênero utilizando variadas metodologias. Considerando os impasses taxonômicos no gênero, optamos por nomear a espécie estudada como Ophiodes cf. fragilis. Os resultados demonstraram ausência de dimorfismo sexual associada a forma e tamanho em Ophiodes cf. fragilis. Quando avaliados os mesmos parâmetros foi possível diferenciar esta espécie de espécimes de Ophiodes fragilis. O sistema urogenital possui morfologia semelhante a anteriormente descritas para Squamata. Foi constatada variação morfológica microscópica associada a períodos reprodutivos e não reprodutivos do ano. Destaca-se a presença do segmento sexual renal nos rins de machos e fêmeas adultas. O hemipênis e o hemiclitóris possuem estruturas microscópicas similares, se distinguindo quanto ao formato e morfologia externa. O número e morfologia dos cromossomos de Ophiodes cf. fragilis foi semelhante ao já conhecido para outras espécies de Ophiodes. Novas análises de citogenética tradicional e molecular foram realizadas pela primeira vez para uma espécie do gênero. Os espécimes de Ophiodes cf. fragilis se locomovem predominantemente pelos modos serpentina e retilíneo, sendo observado a movimentação em determinadas situações do membro posterior vestigial. Há fortes indícios que o membro posterior seja um membro extremamente reduzido, e não vestigial, pela presença de ossículos que o sustentam com atividade metabólica e ligados a uma fina cintura pélvica. Os osteodermos estão presentes em todo o corpo do animal, com a morfologia dos canículos equivalente a descrita para o gênero. O presente estudo apresenta dados inéditos e complementa outras informações previamente conhecidas para o gênero. As metodologias utilizadas e os resultados obtidos poderão ser facilmente replicados e utilizados como base para estudos futuros com outras espécies de Ophiodes. Lizards from genus Ophiodes, popularly known as glass snakes, are characterized by their serpentiform body, lack of forelimbs and rudimentary hindlimbs. They have been recorded in different regions of Brazil and other countries in South America. Despite their morphological peculiarities and wide geographic distribution, studies envolving this genus are scarce. This work was developed aiming to contribute to morphological, reproductive, cytogenetic and locomotor aspects knowledges of species from the genus using several methodologies. Considering some genus taxonomic issues, we chose to name the species studied as Ophiodes cf. fragilis. The results showed no sexual dimorphism associated with shape and size in Ophiodes cf. fragilis. When the same parameters were evaluated, it was possible to differentiate this species from Ophiodes fragilis specimens. The urogenital system has a morphology similar to that previously described for Squamata. Microscopic morphological variation associated with reproductive and non-reproductive periods of the year was found. We highlight the presence of renal sexual segment in males and females adults' kidneys. The hemipenis and hemiclitors have similar microscopic structures, distinguishing themselves in shape and external morphology. The chromosomes number and morphology of Ophiodes cf. fragilis wassimilar to previous described for other species of Ophiodes. New analysis of traditional and molecular cytogenetics were performed for the first time for a species belonging to the genus. Ophiodes cf. fragilis specimens move predominantly by serpentine and rectilinear modes, with movement being observed in certain situations of vestigial posterior limb. There is a strong evidence that the posterior limb is an extremely reduced limb, not a vestigial one, due to presence of ossicles supporting it with metabolic activity and linked to a thin pelvic girdle. Osteoderms are present throughout the animal's body, with canicles morphology equivalent to that described for the genus. The present study presents unpublished data and complements other information previously known for the genus. The methodologies used and the results obtained can be easily replicated and used as a basis for future studies with other species of Ophiodes.