Abstract: Atractus modestus was described based on a single specimen from western Ecuador, and since its original description there have been no further records for this species. During the examination of Ecuadorian collections, we found additional specimens of this poorly known snake. In this paper, we redescribe the holotype of A. modestus, describe the hemipenis and report new specimens, localities, and data on meristic and morphometric variation in the species. We also compare and diagnose this species from all others members of this highly diverse genus.

Keywords: DIPSADINAE, COLUBRIDAE, HEMIPENIS, TAXONOMY

Abstract: A communal oviposition site of western whip snakes, Hierophis viridiflavus, was surveyed every June for 13 years (1990–1997; 2001–2005) at a hilly locality of central Italy (Oriolo Romano, province of Viterbo, about 400 m a.s.l.). The snakes were individually marked, and hence the individual histories of several specimens were assessed over more than one year. The oviposition site was a partially dilapidated building with stony boxes, surrounded by spiny shrubs. Overall, at the study site, 41 gravid females were captured over 13 years of study, together with five adult males and 189 newborn snakes. No non-gravid females were found. Hence, it seems that the study site is used by snakes solely for egg-laying. In total, 73 oviposition events occurred in the study area, and on average the study area was visited annually by 5.46±1.05 gravid females (range 4–7). Gravid females visited the study area for periods of 2.20±1.38 years (range1–5 years); some individuals visited the study site in consecutive (up to three) years, others in alternate (up to five) years, and others at irregular intervals (up to four years). The communal oviposition site was not used preferentially by any specific size category of snakes, but every gravid female in the population, from those presumably young (around 110 cm in length or less) to those presumably old (longer than 120 cm) appeared to use it regularly for laying eggs. There was an effect of year on snake clutch size, but not on the mean body size of snakes. The criteria used by snakes for the selection of the study area as an oviposition site were 1) safe conditions, due to a scarcity of natural predators, and 2) adequate conditions for egg development in a area with resource scarcity for adequate oviposition sites for snakes.

Keywords: ITALY, COLUBRIDAE, MEDITERRANEAN HABITAT, SQUAMATA, REPRODUCTIVE BIOLOGY, REPTILIA

Abstract: We describe and figure for the first time the tadpoles of the hylid frog Scinax luizotavioi from stream backwaters and associated puddles of the Atlantic rainforest of southeastern Brazil. External morphology, colour in life and detailed morphometric data are presented. Diagnostic characteristics that help to distinguish S. luizotavioi tadpoles from other species within the S. catharinae group include labial tooth row formula, disposition of oral papillae and colour in life.

Keywords: MORPHOLOGY, HYLIDAE, DIAGNOSTIC CHARACTERS, SCINAX CATHARINAE GROUP, ANURA, TADPOLE DESCRIPTION

Abstract: In the field, ichthyophiid caecilians are found in soil and epigeic microhabitats – conditions that provide both the phototactic cue of darkness and the thigmotactic cue of tactile contact. In laboratory experiments, we investigated the use of phototaxis and thigmotaxis on refuge selection in a caecilian of the genus Ichthyophis. Refuges that provided light with tactile cues, darkness with tactile cues, or darkness without tactile cues were sufficient in satisfying refuge-seeking behaviour in this species. Tactile stimuli, however, proved to be more preferred than darkness in refuge-seeking behaviour. Our results are consistent with field observations of Ichthyophis species. Thigmotactic cues may be preferred because they are more biologically significant for a burrowing vertebrate that has reduced vision.

Keywords: REFUGE SELECTION, AMPHIBIA, ICHTHYOPHIIDAE, DARKNESS CUES, GYMNOPHIONA, TACTILE CUES

Abstract: The marbled newts Triturus marmoratus and T. pygmaeus are common and readily diagnosed species occurring in central Portugal, but difficult to survey in large and deep ponds. Conversely, embryos of both species are easy to locate but morphologically indistinguishable. We studied a panel of nuclear genetic loci by starch gel electrophoresis (the enzymes Pep-A, Pep-B and Pep-D) and isoelectric focusing techniques (the enzyme Ldh-2, post-embryonic stages only) that together yield a species-specific signature (Cohen's kappa = 1.00). On a locus by locus basis, the scores for correct classification range from kappa = 0.12 to kappa = 0.97. The method allows the reliable, fast and cheap identification of both species across life stages, with better behaviour and performance than mtDNA sequencing (i.e. bar-coding) and nuclear DNA microsatellite profiling. The observed distribution of T. marmoratus and T. pygmaeus over 25 aquatic breeding sites in the Caldas da Rainha area in western Portugal is parapatric, with no mixed populations and no F₁ interspecific hybrids. This demonstrates that T. marmoratus and T. pygmaeus are genetically isolated, even when populations are within the #dispersal##distance##per##generation# range of one another. We consider the data adequate for supporting the species status of T. marmoratus and T. pygmaeus under the Biological Species Concept.

Keywords: ALLOZYMES, PRINCIPAL COORDINATE ANALYSIS, AMPHIBIA

Abstract: A new species of dendrobatid frog of the genus Mannophryne is described from Península de Paria, Estado Sucre, Venezuela. The new taxon, closely related to M. trinitatis, an endemic species of Trinidad, was for a long time considered a continental population of this species. External morphology and call characteristics provide taxonomic distinction between the continental and the insular species, while mitochondrial DNA supports a sister taxon relationship between them. The new species differs from the other members of the genus by its small size (mean snout–vent length 21.5 mm in females, 19.4 mm in males), unpigmented and not well-defined collar and reduced foot webbing. Additionally, the new taxon can be distinguished from Mannophryne trinitatis by: 1) dorsal coloration with a well contrasted pattern; 2) pale dorsolateral stripes not well defined; 3) a paler brown pigmentation on palms and soles; 4) diffuse inguinal stripes; 5) dark markings absent along the anterior margins of forelimbs; 6) advertisement call with a single frequency-modulated note; and 7) differences in 16S and COI mtDNA sequences. Comments on natural history, biogeography and conservation status are provided.

Keywords: TAXONOMY, ADVERTISEMENT CALL, MANNOPHRYNE, SUCRE STATE, AMPHIBIA, MTDNA, BIOGEOGRAPHY

Abstract: Little information exists on the allometric relationship between body mass and snout-vent length (SVL) in lizards, in spite of the relevance of that relationship for the understanding of morphological and ecological parameters. In this study we analyzed the mass-SVL relationship for three Brazilian scincid species (Mabuya agilis, M. macrorhyncha and M. frenata). Our results were indicative of negative allometry for both sexes in all three species, suggesting a general tendency for a relative reduction in bulk as the animal grows. The slopes and intercepts of the regression line did not differ between the sexes in any of the species, except M. macrorhyncha, in which the intercepts differed (suggesting that females would tend to be relatively less robust than males). When the analyses were repeated including juvenile individuals (previously excluded from the data set), the regression for M. agilis tended towards isometry, though it did not change for the remaining species. The results of the present study differ from those found for other Scincidae (including the congener M. heathi), which generally tended towards isometry or positive allometry. We also indicate that mass-SVL regressions may give different results for the same lizard species, depending on whether immature specimens are included or not in the analyses.

Keywords: GROWTH, ALLOMETRY, BRAZIL, SCINCIDAE

Abstract: Elachistocleis bicolor is a poorly known South American microhylid frog. Although it has been claimed to be an ant specialist, there have been no detailed studies of ontogenetic diet change and prey selectivity in this species. We analysed the diet of 114 individuals of this frog through the post-metamorphic ontogeny. We also studied the anurans' morphometric relationships to prey size, and compared diet with prey availability, estimating predation tactics. All prey categories were consumed out of proportion relative to their availability in the environment. The results suggest that the three stages of E. bicolor are selective foragers with a strong preference for ants, although the prey spectrum includes other taxa. The diet of subadults was more similar to that of juveniles, and had the widest diet overlap. Juveniles ate smaller prey, and this could be reducing food competition with older stages. Although the three stages are selective ant foragers, as frogs grow up, there is a partial and gradual change in prey category captured.

Keywords: DIET SPECIALIZATION, ANURA, ONTOGENETIC DIET CHANGE, PREY AVAILABILITY, MICROHYLIDAE, FORMICIDAE

Abstract: Age structure was determined by skeletochronology in Tunisian Rana saharica from two pond sites, one permanent, and the other temporary. Frogs matured at age 3 years; no males older than 5 were found, whereas some females had reached 7 years. Age for age, females were larger than males, but the differences were not significant. There was no obvious difference in age/size relationships between the two ponds. The high variability in juvenile sizes may relate to different life history patterns, as suggested for Moroccan R. saharica.

Keywords: TUNISIA, SKELETOCHRONOLOGY, FROG AGE-SIZE RELATIONSHIPS

Abstract: We tested the hypothesis that the costs of thermoregulation (e.g. predation) can affect the preferred body temperature (T_p, the #target# body temperature in thermoregulation) of reptiles. In European adders (Vipera berus), juveniles face higher predation risks than adults. We compared T_p between adult and juvenile adders and found that the T_p of juveniles was approximately 5 °C lower than that of adults, while adult males and females did not differ. All groups were characterized by narrow T_p ranges. Our results suggest that reptiles may change their T_p in response to the high ecological costs of thermoregulation. Alternative explanations for the reported pattern are also discussed.

Keywords: THERMOREGULATION, SNAKE, PREDATION, BEHAVIOUR

Abstract: Analyses of the gut content of 126 specimens of Atractus reticulatus from the eastern Central Depression of Rio Grande do Sul State, southern Brazil, indicate that this species feeds exclusively on annelids, and primarily on oligochaetes of the family Megascolecidae. Thirty-two stomachs presented 52 items, of which 84.6% were oligochaetes (75.0% family Megascolecidae, 7.7% family Glossoscolecidae, and 1.9% unidentified families), 7.7% were Hirudinea and 7.7% unidentified annelids. Chaetae of oligochaetes were also found in the intestines of 40 additional specimens. Among 20 individuals of A. reticulatus of different size classes captured with some content in the gut, 85.0% were captured at night or in the early hours of morning, indicating foraging activity in these periods. About 83% of the ingested prey were free-living, epigeic annelids, which indicates that A. reticulatus forages mainly on the ground. Prior to swallowing, the annelids were usually oriented and ingested from the anterior portion of the body, a method probably related to autotomy of the prey, which may occur if they are captured from the posterior.

Keywords: ANNELIDS, SNAKES, OLIGOCHAETES, DIET, RIO GRANDE DO SUL

Abstract: The conspecificity of the Chilean Liolaeminae lizards Liolaemus isabelae Navarro & Núñez, 1993 and Liolaemus nigroventrolateralis Ortiz, 1994 is discussed. A careful comparison of the holotype and paratypes of L. nigroventrolateralis with the type series and additional topotype specimens of L. isabelae indicate the conspecificity of the two forms. Furthermore, the characters studied by Ortiz (1994) to diagnose L. nigroventrolateris do not distinguish this species from L. isabelae. There are no distributional or ecological differences between the two species. Therefore, we consider that L. nigroventrolateralis is a synonym of L. isabelae.

Keywords: DISTRIBUTION, ECOLOGY, CONSPECIFICITY, LIOLAEMUS

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