Locomotion and morphological adaptations in the glass lizard Ophiodes cf. fragilis (Raddi, 1820) (Squamata: Anguidae).

There are few studies related to the biological and ecological aspects of the glass snake, a limbless lizard and with a wide geographic distribution. The aim of this study was to analyze the locomotion mode of specimens of Ophiodes cf. fragilis in different substrates and to investigate the morphological adaptations associated with this type of behavior. We observed that the analyzed specimens presented slide-push locomotion modes and lateral undulation in different substrates, using their hind limbs to aid locomotion in three of the four substrates analyzed. The bones of the hind limbs (proximal - femur - and distal - tibia and fibula) were present and highly reduced and the femur is connected to a thin pelvic girdle. Our data support that hind limbs observed in species of this genus are reduced rather than vestigial. The costocutaneous musculature was macroscopically absent. This is the first study of locomotor behavior and morphology associated with locomotion in Ophiodes, providing important information for studies on morphological evolution in the genus.

Ontogenetic skull variation in a shovel-headed amphisbaenian species.

Leposternon microcephalum is a species belonging to the Amphisbaenia, a group of burrowing reptiles. Amphisbaenia present various morphological and physiological adaptations that allow them to penetrate the ground and live underground, through a system of galleries and permanent chambers that they build themselves. Among the morphological adaptations in this group, those of the skull stand out as it serves as the main excavation tool. Four basic skull shapes are recognized: rounded, keeled, shovel-shaped, and spade-shaped. The skull of L. microcephalum belongs to this last type, which is considered the most specialized. The species inhabits soils that are highly compacted and difficult to penetrate. Among the species of Leposternon present in South America, L. microcephalum has the widest distribution, being found in all Brazilian biomes and neighboring countries such as Bolivia, Argentina, Paraguay, and Uruguay. The analysis of the skull of this species was carried out using three-dimensional geometric morphometrics (3D-GMM), a technique that allows comparative analysis, through robust statistical methods, of shape and its variations, using Cartesian coordinate data from a configuration of homologous landmarks. The technique allows the size and shape components of a structure to be analyzed separately. From an ontogenetic point of view, this methodology had also been used to investigate variations in Cynisca leucura, a member of the Amphisbaenidae with a rounded head. Our hypothesis is that the patterns of morphological differentiation in the skull, mainly in the intermediate and occipital regions, are similar in different Amphisbaenia species. Therefore, the objective of this study was to analyze cranial morphological variations in an ontogenetic series of L. microcephalum using 3D-GMM. Computed Tomographic scans of 13 specimens were analyzed: juveniles (N = 8) and adults (N = 5), based on 20 landmarks that characterize the skull. Principal components and regression analyses between shape (dependent variable) and size (independent variable) showed a clear difference between the cranial morphological pattern of juvenile individuals and that of adults. For instance, young specimens tend to have a dorsoventrally tall neurocranium, with the tip of the snout more anteriorly oriented and its dorsal border subtly curved. Dorsally, the parietal region is thicker and smoothly dome-shaped in juveniles. As in C. leucura, the variation was strongly correlated with the size change from juvenile to adult, indicating a dominant role for ontogenetic allometry in determining skull shape.

Updated list of non-volant small mammals from the Serra da Bocaina National Park, southeastern Brazil / Lista atualizada dos pequenos mamíferos não-voadores do Parque Nacional da Serra da Bocaina, sudeste do Brasil

Abstract In the core of the Atlantic Forest biome, the Serra da Bocaina National Park (SBNP) is located in the Atlantic Forest Southeast area of endemism for vertebrates. Filling gaps in knowledge about the spatial distribution and occurrence of species in national parks is of fundamental importance to know how many species are protected and to guide conservation initiatives. Here we updated the non-volant small mammal species list of the SBNP, providing new data on species list and abundance, with species identified mainly by karyotype and/or molecular analysis. Twelve sampling sessions with a capture-mark-recapture approach were carried out in four sites in the SBNP from 2013 to 2016, during the paving works of the state highway RJ-165 (Estrada Parque Paraty-Cunha), municipality of Paraty, state of Rio de Janeiro, Brazil. Non-volant small mammals (Rodentia and Didelphimorphia) were sampled using Sherman® and Tomahawk® live traps (18,987 trap-nights) and pitfall traps (4,591 trap-nights). Thirty-two species (11 marsupials and 21 rodents) were recorded from 1,185 captured specimens. Species richness ranged from 18 to 28 between sites. Ten and 11 species were exclusively captured in live traps and pitfall traps, respectively. The observed richness (32 species) represented 91.4% of the estimated species richness for the study area. Sites 2 and 4 were the most similar to each other regarding species composition, and site 3 was the most dissimilar. The species with highest relative abundance were Euryoryzomys russatus (14%) and Delomys dorsalis (14%), while six species had relative abundances lower than 1%. Fourteen and 17 species were identified by karyotype and molecular analysis, respectively. The present study added 22 species to the park's non-volant small mammals list, which now has 37 species with confirmed occurrence. This species richness found in the SBNP is one of the highest ever recorded for the group of non-volant small mammals in protected areas of the Atlantic Forest in Brazil, corroborating the Serra da Bocaina region as a biodiversity hotspot.

Resumen No cerne do bioma Mata Atlântica, o Parque Nacional da Serra da Bocaina (PNSB) está localizado na área Sudeste de endemismo para vertebrados na Mata Atlântica. Preencher lacunas de conhecimento sobre a distribuição espacial e ocorrência das espécies em parques nacionais é de fundamental importância para saber quantas espécies estão protegidas e orientar iniciativas de conservação. Aqui atualizamos a lista de espécies de pequenos mamíferos não-voadores do PNSB, fornecendo novos dados sobre a lista de espécies e abundância, com espécies identificadas principalmente por análises cariotípicas e/ou molecular. Doze sessões de amostragem com uma abordagem de captura-marcação-recaptura foram realizadas em quatro áreas no PNSB de 2013 a 2016, durante as obras de pavimentação da rodovia estadual RJ-165 (Estrada Parque Paraty-Cunha), município de Paraty, estado do Rio de Janeiro, Brasil. Os pequenos mamíferos não-voadores (Rodentia e Didelphimorphia) foram amostrados usando armadilhas de captura viva Sherman® e Tomahawk® (18.987 armadilhas-noite) e armadilhas de queda (4.591 armadilhas-noite). Trinta e duas espécies (11 marsupiais e 21 roedores) foram registradas em 1.185 espécimes capturados. A riqueza de espécies variou de 18 a 28 entre as áreas de amostragem. Dez e 11 espécies foram capturadas exclusivamente em armadilhas de captura viva e armadilhas de queda, respectivamente. A riqueza observada (32 espécies) representou 91,4% da riqueza de espécies estimada para a área de estudo. As áreas 2 e 4 foram as mais semelhantes entre si quanto à composição de espécies, e a área 3 foi a mais dissimilar. As espécies com maior abundância relativa foram Euryoryzomys russatus (14%) e Delomys dorsalis (14%), enquanto seis espécies tiveram abundâncias relativas inferiores a 1%. Quatorze e 17 espécies foram identificadas pelo cariótipo e por análise molecular, respectivamente. O presente estudo acrescentou 22 espécies à lista de pequenos mamíferos não-voadores do parque, que passou a contar com 37 espécies com ocorrência confirmada. Essa riqueza de espécies encontrada no PNSB é uma das maiores já registradas para o grupo dos pequenos mamíferos não-voadores em áreas protegidas da Mata Atlântica no Brasil, corroborando a região da Serra da Bocaina como um hotspot de biodiversidade.

Skull morphology of bottlenose dolphins from different ocean populations with emphasis on South America.

The bottlenose dolphin, genus Tursiops, is cosmopolitan occurring in tropical and temperate regions, with morphological variation between and within different oceans. Since the genus' taxonomy has been under discussion for a long time, this work aimed at analyzing the cranial variability of T. truncatus from different regions of the world. Geometric Morphometrics analyses were performed in 201 skulls of adult specimens, on dorsal, ventral, and lateral views, from the Eastern North Pacific, Eastern North Atlantic, Eastern South Atlantic, and Western South Atlantic oceans. The results indicate differences between individuals that inhabit the Atlantic and Pacific oceans. Within the Atlantic Ocean, there is an evident longitudinal differentiation of specimens from the eastern and western regions. A latitudinal separation was also observed, considering specimens from the North and South Atlantic Ocean. In the Western South Atlantic statistical differences were found between two morphological groups, identified as T. gephyreus (sensu Lahille, 1908) and T. truncatus, and the cross-validation presented 98% as minimum confidence for correct classification of these two groups. The present study provides strong morphological support to consider these two lineages as separate species.

Variation in the skull morphometry of four taxonomic units of Thrichomys (Rodentia: Echimyidae), from different Neotropical biomes.

The echimyid rodents of the genus Thrichomys vary considerably in their behavior and feeding ecology, reflecting their occurrence in environments as different as the Caatinga, Cerrado, Pantanal, and Chaco biomes. While the genus was originally classified as monospecific, a number of Thrichomys species have been recognized in recent decades, based on morphometric, cytogenetic, and molecular analyses. While Thrichomys is well studied, the variation found in its cranial morphology is poorly understood, given the taxonomic and ecological complexities of the genus. Using a geometric morphometric approach, we characterized the differences found in the cranial morphology of four Thrichomys taxonomic units, including three established species, Thrichomys apereoides, Thrichomys fosteri, and Thrichomys laurentius, and one operational taxonomic unit (OTU), Thrichomys aff. laurentius. No significant differences were found among these units in cranium size, but significant variation was found in skull shape. The Procrustes distances provided a quantification of the differences in the shape of the skull, with the largest distances being found between T. aff. laurentius and T. fosteri in the dorsal view, and between T. aff. laurentius and T. apereoides in the ventral view. A Discriminant Function Analysis (DFA) with cross-validation determined that the pairings with the highest correct classification were T. aff. laurentius vs. T. apereoides and T. aff. laurentius vs. T. fosteri, in both views. The principal variation in skull shape was found in the posterior region and the zygomatic arch, which may be related to differences in diet.

Analysis of the spatio-temporal parameters of gaits in Dasypus novemcinctus (Xenarthra: Dasypodidae)

Armadillos comprise a particular group of armoured animals whose functional morphology of locomotion remains unclear. For the first time, the kinematic patterns of Dasypus novemcinctus are analysed. Eight specimens of nine­banded armadillos were studied at a research institute in São Paulo State, Brazil. The individuals were induced to cross a horizontal corridor and each gait performed during the time each of them was kept inside this structure was recorded to a detailed analysis posteriorly performed in a computer program. Four parameters regarding speed range were considered: stride frequency (Hz) (1/stride period), stride length (m), speed (ms−1) and duty factor (%). A total of 89 strides have been analysed among symmetrical (60.6%) and asymmetrical gaits (39.4%), and six footfall patterns were here reported as follows: lateral sequences (symmetrical), transverse gallop, canter, bound, half­bound and crutch walk (asymmetrical). This kind of analysis implements our knowledge on the locomotory aspects of these animals, hence contributing to the improvement of our knowledge on this still poorly known group

Skull variation in a shovel-headed amphisbaenian genus, inferred from the geometric morphometric analysis of five South American Leposternon species.

Amphisabenia is a group of squamates adapted for a fossorial lifestyle. The skull is the animal's the main digging tool, and can present one of four principal shapes. The shovel-headed shape is considered to be the most specialized for digging. The South American genus Leposternon presents a shovel-headed morphotype, and is widely distributed on this continent. The general shovel-headed skull pattern may vary considerably, even within the same genus, and we hypothesized that this variation may be influenced primarily by body size and geographical factors. This study investigated the variation in skull size and shape among five Leposternon species, and examined the potential relationship between this variation and the size of the specimens and bioclimatic variables, through a geometric morphometric approach. Significant morphological variation was found among the species, and was also related systematically to body size and the geographical distribution of the specimens. As even subtle differences in the skull size or shape may represent significant modification in bite force and digging capacity and digging speed, the cranial variation found among the Leposternon species and specimens may have a direct influence on their diet and locomotor performance. Our results, together with direct observations of some of these species, suggest that shovel-headed amphisbaenians may be able to penetrate different soil types under a range of climatic conditions, especially considering the ample, but often sympatric distribution of the species studied here.

Bats of the Serra da Bocaina National Park, southeastern Brazil: an updated species list and a distribution extension for Trinycteris nicefori (Sanborn, 1949) / Morcegos do Parque Nacional da Serra da Bocaina, sudeste do Brasil: lista de espécies atualizada e expansão de distribuição para Trinycteris nicefori (Sanborn, 1949)

Abstract: The Serra da Bocaina National Park (SBNP) is a large remnant of Atlantic Forest located within an endangered biodiversity hotspot, which contributes to the connectivity among protected areas in the region. Despite the ecological importance of the SBNP, its bat fauna is poorly-known, and no comprehensive inventory is available. The present study provides an updated list of the bat species found in the SBNP. The four-year study was based on a capture-mark-recapture approach at four sites within the park, in the municipality of Paraty, Rio de Janeiro state, Brazil. A total of 22 bat species were recorded, representing two families, Phyllostomidae (n = 19 species) and Vespertillionidae (n = 3). This added 14 species to the known bat fauna of the SBNP, which is hereby updated to 24 species, including Dermanura cinerea Gervais, 1856, Platyrrhinus recifinus (Thomas, 1901), and Myotis ruber (É. Geoffroy, 1806), which are listed as endangered in Rio de Janeiro state. The specimen of Trinycteris nicefori (Sanborn, 1949) captured in the present study is the first record of the occurrence of this species in Rio de Janeiro state. This record extends the geographic range of the species by approximately 650 km to the southeast. Additional inventories, in particular at poorly-studied Atlantic Forest sites, combined with environmental suitability analyses, and taxonomic and biogeographic data, are urgently required to elucidate the distribution of many Brazilian bat species, such as T. nicefori.

Resumo: O Parque Nacional da Serra da Bocaina (PNSB) é um grande remanescente de Mata Atlântica localizado em um hotspot de biodiversidade ameaçado, que contribui para a conectividade entre áreas protegidas na região. Apesar da importância ecológica do PNSB, a sua quiropterofauna é pobremente conhecida e nenhum inventário abrangente está disponível. O presente estudo fornece uma lista atualizada das espécies de morcegos do PNSB. O estudo de quatro anos foi baseado em uma abordagem de captura-marcação-e-recaptura em quatro localidades dentro do parque, no município de Paraty, estado do Rio de Janeiro, Brasil. Um total de 22 espécies de morcegos foi registrado, representando duas famílias, Phyllostomidae (n = 19 espécies) e Vespertillionidae (n = 3). Isso adiciona 14 espécies à quiropterofauna conhecida do PNSB, que é atualizada para 24 espécies, incluindo Dermanura cinerea Gervais, 1856, Platyrrhinus recifinus (Thomas, 1901) e Myotis ruber (É. Geoffroy, 1806), que são listadas como ameaçadas de extinção no estado do Rio de Janeiro. O espécime de Trinycteris nicefori (Sanborn, 1949) capturado no presente estudo representa o primeiro registro da espécie no estado do Rio de Janeiro. Esse registro expande a distribuição geográfica da espécie aproximadamente 650 km a sudeste. Inventários adicionais, particularmente em localidades de Mata Atlântica pobremente estudadas, combinados com análises de adequação, e estudos taxonômicos e biogeográficos, são urgentemente necessários para esclarecer a distribuição de muitas espécies de morcegos brasileiras, como T. nicefori.

Body and skull morphometric variations between two shovel-headed species of Amphisbaenia (Reptilia: Squamata) with morphofunctional inferences on burrowing.

BACKGROUND: Morphological descriptions comparing Leposternon microcephalum and L. scutigerum have been made previously. However, these taxa lack a formal quantitative morphological characterization, and comparative studies suggest that morphology and burrowing performance are be related. The excavatory movements of L. microcephalum have been described in detail. However, there is a lack of studies comparing locomotor patterns and/or performance among different amphisbaenids sharing the same skull shape. This paper presents the first study of comparative morphometric variations between two closely related amphisbaenid species, L. microcephalum and L. scutigerum, with functional inferences on fossorial locomotion efficiency. METHODS: Inter-specific morphometric variations were verified through statistical analyses of body and cranial measures of L. microcephalum and L. scutigerum specimens. Their burrowing activity was assessed through X-ray videofluoroscopy and then compared. The influence of morphological variation on the speed of digging was tested among Leposternon individuals. RESULTS: Leposternon microcephalum and L. scutigerum are morphometrically distinct species. The first is shorter and robust with a wider head while the other is more elongated and slim with a narrower head. They share the same excavatory movements. The animals analyzed reached relatively high speeds, but individuals with narrower skulls dug faster. A negative correlation between the speed and the width of skull was determined, but not with total length or diameter of the body. DISCUSSION: The morphometric differences between L. microcephalum and L. scutigerum are in accord with morphological variations previously described. Since these species performed the same excavation pattern, we may infer that closely related amphisbaenids with the same skull type would exhibit the same excavatory pattern. The negative correlation between head width and excavation speed is also observed in others fossorial squamates. The robustness of the skull is also related to compression force in L. microcephalum. Individuals with wider heads are stronger. Thus, we suggest trade-offs between excavation speed and compression force during burrowing in this species.

Kinematic description of the vertical climbing of Dasypus novemcinctus (Xenarthra, Dasypodidae): the first report of this ability in armadillos

Armadillos are well-known quadrupeds whose digging abilities classify them differently into many fossorial categories. This is the first time a kinematic description is provided on the vertical climbing sequences performed by these animals, more specifically by the nine-banded armadillo Dasypus novemcinctus. After an opportunistic observation of climbing behavior, video recording sessions were setup to document wire mesh climbing. The individuals climbed up to its top showing four distinct ways of vertical progression, such as lateral and diagonal-sequences as well as few styles that resemble the asymmetrical motions used by quadrupeds on land. Sharp claws were used as strategic points of attachment on a substrate, and tails provided additional support during vertical progression. Thus, the locomotory repertoire of armadillos is far more diverse than previously considered.

RESUMO. Descrição cinemática da escalada vertical de Dasypus novemcinctus (Xenarthra, Dasypodidae): o primeiro registro desta habilidade em tatus. Tatus são quadrúpedes bem conhecidos cujas habilidades escavatórias classificam-nos de forma diferenciada em diversas categorias fossoriais. Esta é a primeira vez que a descrição cinemática de sequencias de escalada vertical realizada por estes animais, mais especificamente pelo tatu de nove-bandas Dasypus novemcinctus, é feita. Após uma observação oportunística de escalada, sessões de gravação em vídeo foram realizadas a fim de documentar a escalada em grade. Os indivíduos escalaram-na até o topo exibindo quatro maneiras distintas de progressão vertical, tais como sequencias laterais e diagonais e alguns estilos que se assemelhavam aos movimentos assimétricos usados por quadrúpedes em terra. Garras afiadas foram usadas como pontos estratégicos de adesão ao substrato, e as caudas forneceram suporte adicional durante a progressão vertical. Assim sendo, o repertório locomotor dos tatus é bem mais diverso do que até então considerado.

Origin and antimeric distribution of the femoral nerves in New Zealand rabbits / Origen y distribución antimérica del nervio femoral en conejos Nueva Zelanda

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.

Age and sex-related geometrical variation of ramus mandibulae of Sus scrofa's (Mammalia: Artiodactyla) jaws / Variaciones geométricas del ramus mandibulae en mandíbulas de Sus scrofa (Mammalia: Artiodactyla) según edad y sexo

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.

Comparative intestinal histomorphology of five species of Phyllostomid bats (Phyllostomidae, Microchiroptera): ecomorphological relations with alimentary habits / Histomorfometría comparativa de intestino de cinco especies de murciélagos Phyllostomideos (Phyllostomidae, Microchiroptera): relaciones ecomorfológicas con hábitos alimentarios

The intestines of Sturnira lilium, Phyllostomus hastatus, Carolliaperspicillata, Glossophagasoricinaíind Desmodus 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...

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...

Excavatory cycle of Leposternon microcephalum Wagler, 1824 (Reptilia, Amphisbaenia) / Ciclo excavatorio de Leposternon microcephalum Wagler, 1824 (Reptilia, Amphisbaenia)

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 caída 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.

Comparative study on the forefoot and hindfoot intrinsic muscles of some cavioidea rodents (Mammalia, Rodentia).

The present study compares the forefoot and hindfoot musculature of five representative species of Cavioidea rodents. In all species, the musculature of both forefeet and hindfeet have the same array regardless of the absence of digit I in the manus of Hydrochaeris hydrochaeris and Cavia porcellus. Our results suggest a tendency in these species towards a three-digit system, with a functional loss of digit V and a predominance of digit III in their forefeet. In the same way, the muscular reduction of digit I in the other rodents analyzed indicates a four-digit system with predominance of digit II in Myoprocta acouchy and Dasyprocta leporina and of digit V in Agouti paca. There seems to be an association between the muscular arrangement and functional axis of the foot, raising the general question why this axis runs between the third and forth digit, or along the third digit.

Topographical Anatomy of the Blunthead Treesnake, Imantodes cenchoa (Linnaeus, 1758) (Colubridae: Xenodontinae) / Anatomía Topográfica de la Serpiente Bejucillo Cabezona, Imantodes cenchoa (Linnaeus, 1758) (Colubridae: Xenodontinae)

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.