A new four-pored Amphisbaena Linnaeus, 1758 (Amphisbaenia, Amphisbaenidae) from the north of Espinhaço Mountain Range, Brazil

A new species of Amphisbaena is described from the north of Espinhaço Mountain Range, municipality of Caetité, state of Bahia, Brazil. Amphisbaenaamethysta sp. nov. can be distinguished from its congeners by the following combination of characters: (1) snout convex in profile, slightly compressed not keeled; (2) pectoral scales arranged in regular annuli; (3) four precloacal pores; (4) distinct cephalic shields; (5) 185-199 dorsal half-annuli; (6) 13-16 caudal annuli; (7) conspicuous autotomic site between 4th-6th caudal annuli; (8) 16-21 dorsal and ventral segments at midbody; (9) 3/3 supralabials; (10) 3/3 infralabials; and (11) smooth and rounded tail tip. The new species is the 71st species of genus with four precloacal pores, and the 22nd species from the Caatinga morphoclimatic domain. The identification of Amphisbaenaamethysta sp. nov. indicates that the reptile fossorial fauna in the Espinhaço Mountain Range region is far from being completely known and that it may harbour a much greater diversity of endemic taxa.

Food capture and escape behavior of Leposternon microcephalum Wagler, 1824 (Squamata: Amphisbaenia)

Amphisbaenians are fossorial reptiles that have a cylindrical and elongated body covered with scales arranged in rings, and are all apodal, except for the three species of the genus Bipes. The amphisbaenian diet consists of a variety of invertebrates and small vertebrates. As these animals live underground, many aspects of their natural history are difficult to study. Most feeding studies of amphisbaenians have focused on the composition of the diet and feeding ecology, and the data available on feeding behavior are based on precursory observations. The present study describes the food capture behavior of Leposternon microcephalum Wagler, 1824 in captivity. In this experiment we used non-live bait (moist cat food), which was placed near a burrow opening, on the surface of the substrate. Three animals were monitored visually and filmed using cellphone cameras deployed at fixed points, to capture images from the dorsal and lateral perspectives of the study subjects. Two principal types of behavior were observed: the capture of food and defense mechanisms. The strategies used to capture the food were similar to those observed in other fossorial species. Although the backward movement has already been observed and described, we were able to record this movement being used as an escape strategy. These findings enrich our knowledge on different aspects of the natural history of the amphisbaenians.

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.

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.

M, Vechio FD, Clemente CA. A new Amphisbaena (Squamata: Amphisbaenidae) from southern Espinhaço Range, southeastern Brazil

A new species of Amphisbaena is described from a semi-deciduous forest in Conceição do Mato Dentro, southern Espinhaço Range, Minas Gerais, Brazil. The following combined characters can diagnose the new species from all congeners: head round-shaped; two or three precloacal pores sequentially arranged; 190-199 body annuli; 2-3 lateral annuli; 23-25 caudal annuli; autotomy sites on caudal annuli 7-9; 12-14 dorsal segments on midbody annulus; 14-16 ventral segments on midbody annulus; three supralabials; three infralabials; postmalar row present or absent; dorsum light brown, with cream intersegmental sutures; venter cream. To date, the new species is known only from the Espinhaço Range, highlighting the importance of conservation actions for these mountains.

Reptiles of the municipality of Juiz de Fora, Minas Gerais state, Brazil

The Atlantic Forest of the state of Minas Gerais, as well as the remnants of this domain in the rest of Brazil, suffers a marked reduction in size and anthropogenic alteration. This habitat degradation is directly reflected in the decrease of species richness within these natural environments. In this sense, the inventory of extant species is necessary to understand the species composition of regions under threat. Despite the great richness of existing reptile species in Minas Gerais, the level of knowledge about the fauna in this state is considered unsatisfactory and very fragmented. The aim of this study was to record the composition of the reptile fauna of the municipality of Juiz de Fora through the revision of specimens housed at the Herpetological Collection of the Federal University of Juiz de Fora (CHUFJF-Reptiles) and published papers. Better documentation of the reptilian fauna for the region not only expands the knowledge of the herpetofauna of Minas Gerais, but also contributes to regional conservation planning, such as "Biota Minas" program in the states of the Minas Gerais, Brazil. A total of 41 reptile species (two freshwater turtles, two amphisbaenians, 13 lizards and 24 snakes) belonging to 12 families were recorded. We highlight the record of the freshwater turtle Hydromedusa maximiliani, which is considered a species sensitive to anthropogenic impact and currently is seen only in protected areas in Juiz de Fora, as well as Ecpleopus gaudichaudii, Enyalius brasiliensis, Heterodactylus imbricatus, Placosoma glabellum and Micrurus corallinus, that are dependent on well-preserved forest areas. The reptile composition is more similar to Viçosa and other surrounding regions, despite the presence of many species that are not shared between these locations. This fact demonstrates the importance of the collection in terms of representativeness of the local and regional fauna as well as providing a valuable source of information for future studies of Brazilian herpetofauna in general.