Robles C.I.,Institute Herpetologia |
Robles C.I.,CONICET |
Halloy M.,Institute Herpetologia
Herpetological Journal | Year: 2010
Investigating space use in animals and determining the amount of overlap with neighbours may help to understand whether territoriality is part of a social system, and can help in inferring possible reproductive strategies of males and females. Here we examine these issues in the lizard Liolaemus quilmes from northwestern Argentina based on space use of core areas. We studied a population comprising 119 "large" (LA) and 52 "small" (SA) adults over two consecutive years. We compared core areas of males and females during the reproductive and post-reproductive season, documenting the occurrence and amount of overlap among core areas. We found that the average size of core areas of both LA and SA individuals did not significantly differ from each other across two study years. However, LA male core areas were significantly larger than those of LA females, and LA male core areas were significantly larger than those of SA males. LA and SA male core areas were significantly larger during the reproductive than during the post-reproductive season, possibly indicating the need of males to gain access to females. SA females had significantly smaller core areas during the reproductive season than during the post-reproductiveseason, whereas LA female core areas were not different between seasons. The amount of core area overlap among males did not exceed 23%, supporting the idea of territory defence. Female core areas did not overlap. The core areas of LA males and females overlapped with up to two females and three males, respectively, suggesting a polygynandrous mating system.
Vera Candioti M.F.,Institute Herpetologia |
Altig R.,Mississippi State University
Biological Journal of the Linnean Society | Year: 2010
Labial teeth of anuran tadpoles are keratinized structures derived from the activity of a single epidermal cell of the oral labia; they are not homologous with adult anuran teeth, nor with teeth of other vertebrates. The present study comprises a first approach for studying labial tooth shape variation that will be useful for future studies of comparative development and the functional mechanics of feeding structures. We examined interspecific shape variations in the labial teeth of anuran tadpoles and searched for correlations of these variations with ecomorphological guilds and phylogeny. Species ordination shows that important variations at various taxonomic levels are related mainly to the general curvature of the tooth axis, the angle between the labial tooth base and tip, head length and curvature, and sheath width. The teeth of most basal taxa are broad-based and curved, although some broad-based teeth also characterize some phthanobatrachian species. Teeth of hyloids and ranoids differ in the oral angle, overall curvature, and sheath width. A phylogenetically independent ecomorphological effect is significant only for lotic suctorial and gastromyzophorous guilds; teeth in these forms have short, thick and curved heads, wide sheaths, and generally acute oral angles. The lack of a significant correlation between labial tooth shape and trophic guilds suggests that labial tooth harvesting ability has a wide latitude that could be particularly functional only under specific circumstances. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society.
Zaracho V.H.,Northeast National University |
Lavilla E.O.,Institute Herpetologia
Iheringia - Serie Zoologia | Year: 2015
Studies on diversity and natural history of anuran communities are basic to distinguish natural fluctuations from those due to human impacts (a key tool in conservation programs), to assess the role they play in ecosystems dynamics and to allow comparison of diversity gradients. With those objectives, this paper analyzes diversity, temporal and spatial distribution, and calling daily time of the anurans from three breeding sites at Esteros del Iberá, in northeastern Argentina. Samples were taken monthly, between July 2008 and June 2010 We recorded 26 species belonging to five families: Bufonidae (2), Hylidae (11), Leptodactylidae (11), Microhylidae (1) and Odontophrynidae (1). The study highlights variations in species richness per site, in the period, frequency and calling daily time and in the densities of calling males. The species richness is comparable to that of other similar wetlands, including the dominance of leptodactylids and hylid, a frequent pattern in Neotropical assemblages. The concentration of active species in the warmest and wettest months was associated with changes in temperature and rainfall, which were identified as important factors that initiate reproductive activity in seasonal environments. © 2015, Fundacao Zoobotanica do Rio Grande do Sul. All rights reserved.
Barrionuevo J.S.,Museo Argentino de Ciencias Naturales Bernardino Rivadavia |
Barrionuevo J.S.,Institute Herpetologia
Journal of Morphology | Year: 2013
The osteological diversity among species of Telmatobius has been considered conservative. Nonetheless, the degree of ossification of several features varies both intraspecifically and interspecifically. Herein, intraspecific osteological variation and postmetamorphic ontogenetic changes in osteological features are described in Telmatobius oxycephalus. These data are compared with published descriptions of congeners. There is a considerable intraspecific osteological variation in T. oxycephalus, with cranial characters varying polymorphically, and the hyoid and postcranial characters being sexually dimorphic. This intraspecific variation is expressed by subtle differences in the degree of ossification or mineralization. Interspecific variation also can be described in terms of differential development of osteological features; these differences are more obvious than intraspecifically variable characters. The adult skeletons of several species of Telmatobius resemble the morphology observed in early stages of postmetamorphic development of T. oxycephalus. This is especially evident in the neopalatines, parasphenoid, sphenethmoid, exoccipitals, prootics, vomers, nasals, and plectra. These results suggest that within the conservative osteological architecture of Telmatobius, the variation observed is the result of heterochronic changes during the ossification process. © 2012 Wiley Periodicals, Inc.
Scrocchi G.J.,Institute Herpetologia |
Check List | Year: 2012
Phalotris sansebastiani is recorded for the first time in Argentina based on five specimens from Jujuy and Salta provinces, and its characters are compared with Argentinean specimens of P. tricolor. © 2012 Check List and Authors.
Halloy M.,Institute Herpetologia
Herpetological Journal | Year: 2012
Visual displays in lizards are used to convey information related to species, sex, reproductive state, context and even individuality. Two displays that have been reported are headbobs, up and down movements of the head, and forelimb waves, circular movements of the forelegs, the former display generally being more conspicuous and frequent than the latter. Here I investigated these two displays in an iguanian neotropical species, Liolaemus quilmes, from northwestern Argentina. One-hundredand- fifteen males and females were filmed over six years, in their habitat, during their daily activities. Headbob and forelimb display rates were compared between males and females and between the reproductive and postreproductive seasons. In addition, the relation between headbob display rates and home range size was explored. As reported for many iguanian lizards, males made significantly more headbob displays than females in both the reproductive and post-reproductive seasons. They also performed more forelimb waves than females in both seasons. Finally, no correlation was found between headbob display rates and home range sizes in any of the two seasons, suggesting that although headbob displays have been associated with territorial defence it does not seem to be associated with the size of the defended area.
Grazziotin F.G.,University of Sao Paulo |
Grazziotin F.G.,São Paulo State University |
Zaher H.,University of Sao Paulo |
Murphy R.W.,Royal Ontario Museum |
And 6 more authors.
Cladistics | Year: 2012
We present a phylogenetic analysis of the New World dipsadids based on an expanded data matrix that includes 246 terminal taxa including 196 dipsadids. The species are sampled for eight genes (12S, 16S, cytb, nd2, nd4, bdnf, c-mos, rag2). The data are explored using two distinct optimality procedures-maximum parsimony and maximum likelihood-and two alignment strategies-dynamic homology and static homology. Two previously unsampled dipsadid genera, Sordellina and Rhachidelus, are now included in the analysis. The definitions of the genera, Erythrolamprus, Clelia, Hypsirhynchus, Philodryas and Phimophis, and the tribes Alsophiini, Echinantherini and Conophiini, are revised. In order to maintain monophyly, the genus Umbrivaga is synonymized with Erythrolamprus, and two new genera are erected to accommodate Phimophis iglesiasi and Clelia rustica, as well as their closely related species. The West Indian genera Schwartzophis, Darlingtonia, Antillophis and Ocyophis are resurrected. © The Willi Hennig Society 2012.
Guerra C.,Institute Herpetologia |
Diseases of Aquatic Organisms | Year: 2016
Agricultural landscapes support large amphibian populations because they provide habitat for many species, although agriculture affects amphibians through various mechanisms. Pollution with agrochemicals is the major threat to amphibian populations after habitat loss, as chemicals alter the ecophysiology of amphibians, putting their health and survival at risk. We aimed to assess the effect of different environments, sites, width of forest buffers and sampling years on the health of amphibians, which was estimated through the prevalence of malformations and body condition. During 3 yr of pitfall trapping, we captured 4491 amphibians. The prevalence of malformations was higher in the croplands than in the forests, while the body condition was better within forests. The prevalence of malformations was higher in the narrower forest site than in the wider forest site. The prevalence of malformations and the body condition were higher in the third year. The prevalence of malformations differed by species. We found 11 types of malformation, which mainly affected limbs and were unilateral or bilaterally asymmetrical. Our results showed that the prevalence of malformations and body condition reflect different aspects of the health of amphibians and that forest individuals are healthier than those from croplands. The results also highlight the importance of spatial configuration besides the conservation of natural habitats to preserve healthy amphibians in agricultural landscapes. The types of malformation that we found suggest that agrochemicals could be an important cause of malformations.
Faivovich J.,Museo Argentino de Ciencias Naturales Bernardino Rivadavia |
Faivovich J.,University of Buenos Aires |
Ferraro D.P.,Museo Argentino de Ciencias Naturales Bernardino Rivadavia |
Basso N.G.,CONICET |
And 4 more authors.
Cladistics | Year: 2012
Species of the genus Pleurodema are relatively small, plump frogs that mostly occur in strong-seasonal and dry environments. The genus currently comprises 14 species distributed from Panama to southern Patagonia. Here we present a phylogenetic analysis of Pleurodema, including all described species and several outgroups. Our goals include testing its monophyly and the monophyly of the species groups that were historically proposed, and studying the evolution of some character systems, particularly macroglands and egg-clutch structure; this last point also provided the chance for a discussion of foam nest evolution in anurans. Our dataset includes portions of the mitochondrial genes cytochromeb, 12S, 16S, and the intervening tRNA Val; the nuclear gene sequences include portions of rhodopsin exon 1 and seven in absentia homolog I. Our results support a clade composed of Pleurodema and including the monotypic SomuncuriaLynch, 1978 nested within it. The latter genus is therefore considered a junior synonym of Pleurodema and its sole species is added to this genus. Furthermore, our results indicate the non-monophyly of several species groups proposed previously. We recognize four clades in Pleurodema: the P. bibroni clade (P. bibroni, P. cordobae and P. kriegi), the P. thaul clade (P. bufoninum, P. marmoratum, P. somuncurensis and P. thaul), the P. brachyops clade (P. alium, P. borellii, P. brachyops, P. cinereum, P. diplolister and P. tucumanum) and the P. nebulosum clade (P. guayapae and P. nebulosum). Our results further indicate the need for a taxonomic reassessment of P. borellii and P. cinereum (as did previous studies), P. guayapae and P. nebulosum, and the three species in the P. bibroni clade. Pleurodema shows a striking pattern of variation in presence/absence of lumbar glands. Our results indicate multiple losses or independent gains of this character associated with defensive displays. The reproductive modes of Pleurodema include four different egg-clutch structures. The optimization of these indicates that there are at least two independent transformations from the plesiomorphic mode of foam nests to egg-clutch structures involving gelatinous masses of different sorts (ovoid plates, masses, or strings). We hypothesize that these independent transformations could involve changes at the behavioural (the loss of foam beating behaviour by the parent) and/or structural level (transformations involving the pars convoluta dilata, the section of the oviduct where the foam-making substance is secreted). Finally, our study of foam nest evolution in Pleurodema is extended to the other groups of anurans where foam-nesting occurs, on the basis of available data and recent phylogenetic hypotheses. In the different hyloid groups where it occurs, foam-nesting evolved from clutches laid in water. However, in all ranoids in which foam-nesting occurs, it evolved from terrestrial clutches, with eggs laid hanging in vegetation, or, if the clutches are laid on a restricted volume of water, involving endotrophic development. © The Willi Hennig Society 2012.
Quinteros A.S.,National University of Salta |
Abdala C.S.,Institute Herpetologia
Zootaxa | Year: 2011
We provide evidence for a new species of Liolaemus, which can be included in the L. dorbignyi group within the montanus series. Liolaemus vulcanus sp. nov. was previously confused with L. dorbignyi, but it exhibits states of character which allow us to differentiate the two taxa. The main differences with L. dorbignyi are in the color pattern and in the dorsal scales. Liolaemus vulcanus sp. nov. is saxicolous and it inhabits in rocky hills in the Puna regions of Northwestern Argentina. It is distributed in localities in Antofagasta de la Sierra department in Catamarca Province, Argentina . © 2011 Magnolia Press.