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The diversity of habitats generated by the Andes uplift resulted a mosaic of heterogeneous environments in South America for species to evolve a variety of ecological and physiological specializations. Species in the lizard family Liolaemidae occupy a myriad of habitats in the Andes. Here, we analyze the tempo and mode of evolution in the thermal biology of liolaemids. We assessed whether there is evidence of local adaptation (lability) or conservatism (stasis) in thermal traits. We tested the hypothesis that abiotic factors (e.g., geography, climate) rather than intrinsic factors (egg-laying [oviparous] or live-bearing [viviparous], substrate affinity) explain variation in field active body temperature (Tb ), preferred temperature (Tp ), hours of restriction of activity, and potential hours of activity. Although most traits exhibited high phylogenetic signal, we found variation in thermal biology was shaped by geography, climate, and ecological diversity. Ancestral character reconstruction showed shifts in Tb tracked environmental change in the past ∼20,000 years. Thermal preference is 3°C higher than Tb , yet exhibited a lower rate of evolution than Tb and air temperature. Viviparous Liolaemus have lower Tb s than oviparous species, whereas Tp is high for both modes of reproduction, a key difference that results in a thermal buffer for viviparous species to cope with global warming. The rapid increase in environmental temperatures expected in the next 50-80 years in combination with anthropogenic loss of habitats are projected to cause extirpations and extinctions in oviparous species.

Given the rapid loss of biodiversity as consequence of climate change, greater knowledge of ecophysiological and natural history traits are crucial to determine which environmental factors induce stress and drive the decline of threatened species. Liolaemus montanezi (Liolaemidae), a xeric-adapted lizard occurring only in a small geographic range in west-central Argentina, constitutes an excellent model for studies on the threats of climate change on such microendemic species. We describe field data on activity patterns, use of microhabitat, behavioral thermoregulation, and physiology to produce species distribution models (SDMs) based on climate and ecophysiological data. Liolaemus montanezi inhabits a thermally harsh environment which remarkably impacts their activity and thermoregulation. The species shows a daily bimodal pattern of activity and mostly occupies shaded microenvironments. Although the individuals thermoregulate at body temperatures below their thermal preference they avoid high-temperature microenvironments probably to avoid overheating. The population currently persists because of the important role of the habitat physiognomy and not because of niche tracking, seemingly prevented by major rivers that form boundaries of their geographic range. We found evidence of habitat opportunities in the current range and adjacent areas that will likely remain suitable to the year 2070, reinforcing the relevance of the river floodplain for the species’ avoidance of extinction.

The predicted rise of global temperatures is of major concern for ectotherms because of its direct impact on their behavior and physiology. As physiological performance mediates a species’ resilience to warming exposure, physiological plasticity could greatly reduce the susceptibility to climate change. We studied the degree to which Diplolaemus leopardinus lizards are able to adjust behavioral and physiological traits in response to short periods of temperature change. We used a split cross design to measure the acclimation response of preferred body temperature (Tp), and the thermal performance curve of resting metabolic rate (RMR) and evaporative water loss (EWL). Our results showed that plasticity differs among traits: whereas Tp and EWL showed lower values in warm conditions, the body temperature at which RMR was highest increased. Moreover, RMR was affected by thermal history, showing a large increase in response to cold exposure in the group initially acclimated to warm temperatures. The reduction of EWL and the increase in optimal temperature will give lizards the potential to partially mitigate the impact of rising temperatures in the energy cost and water balance. However, the decrease in Tp and the sensitivity to the warm thermal history of RMR could be detrimental to the energy net gain, increasing the species’ vulnerability, especially considering the increase of heat waves predicted for the next 50 years. The integration of acclimation responses in behavioral and physiological traits provides a better understanding of the range of possible responses of lizards to cope with the upcoming climatic and environmental modifications expected as a result of climate change.

Liolaemus duellmani is a poorly known, microendemic lizard described from southwestern Mendoza, Argentina, representing the southernmost distribution of the Liolaemus montanus species group. We report the rediscovery of the species after 43 years, presenting the fifth voucher specimen and the second female of L. duellmani. Data on external morphology, activity, and color photographs are included, and the geographic coordinates of the type locality are discussed.

In ectotherms, temperature exerts a strong influence on the performance of physiological and ecological traits. One approach to understanding the impact of rising temperatures on animals and their ability to cope with climate change is to quantify variation in thermal-sensitive traits. Here, we examined the thermal biology, temperature dependence and thermal plasticity of bite force (endurance and magnitude) in Diplolaemus leopardinus, an aggressive and territorial lizard endemic to Mendoza province, Argentina. Our results indicate that this lizard behaves like a moderate thermoregulator that uses the rocks of its environment as the main heat source. Bite endurance was not influenced by head morphometry and body temperature, whereas bite force was influenced by head length and jaw length, and exhibited thermal dependence. Before thermal acclimation treatments, the maximum bite force for D. leopardinus occurred at the lowest body temperature and fell sharply with increasing body temperature. After acclimation treatments, lizards acclimated at higher temperatures exhibited greater bite force. Bite force showed phenotypic plasticity, which reveals that leopard iguanas are able to maintain (and even improve) their bite force under a rising-temperature scenario. Fil: Vicenzi, Nadia Pamela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Provincia de Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Universidad Nacional de Cuyo. Instituto Argentino de Investigaciones de las Zonas Áridas; Argentina. Universidad Nacional de Cuyo. Facultad de Ciencias Exactas y Naturales; Argentina Fil: Laspiur, Julio Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina. Universidad Nacional de San Juan. Escuela Universitaria de Ciencias de la Salud.; Argentina Fil: Sassi, Paola Lorena. Universidad Nacional de Cuyo. Facultad de Ciencias Exactas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Provincia de Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Universidad Nacional de Cuyo. Instituto Argentino de Investigaciones de las Zonas Áridas; Argentina Fil: Massarelli, Rubén Esteban. Dirección de Recursos Naturales Renovables, Secretaría de Ambiente y Ordenamiento Territorial; Argentina Fil: Krenz, John. University of Minnesota; Estados Unidos Fil: Ibarguengoytía, Nora. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina

In ectotherms, temperature exerts a strong influence on the performance of physiological and ecological traits. One approach to understanding the impact of rising temperatures on animals and their ability to cope with climate change is to quantify variation in thermal-sensitive traits. Here, we examined the thermal biology, temperature dependence and thermal plasticity of bite force (endurance and magnitude) in

The South American lizard genus Liolaemus comprises > 260 species, of which > 60 are recognized as members of the Liolaemus montanus group, distributed throughout the Andes in central Peru, Bolivia, Chile and central Argentina. Despite its great morphological diversity and complex taxonomic history, a robust phylogenetic estimate is still lacking for this group. Here, we study the morphological and molecular diversity of the L. montanus group and present the most complete quantitative phylogenetic hypothesis for the group to date. Our phylogeny includes 103 terminal taxa, of which 91 are members of the L. montanus group (58 are assigned to available species and 33 are of uncertain taxonomic status). Our matrix includes 306 morphological and ecological characters and 3057 molecular characters. Morphological characters include 48 continuous and 258 discrete characters, of which 70% (216) are new to the literature. The molecular characters represent five mitochondrial markers. We performed three analyses: A morphology-only matrix, a molecular-only matrix and a matrix including both morphological and molecular characters (total evidence hypothesis). Our total evidence hypothesis recovered the L. montanus group as monophyletic and included ≥ 12 major clades, revealing an unexpectedly complex phylogeny. Fil: Abdala, Cristian Simón. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; Argentina Fil: Quinteros, Andres Sebastian. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Bio y Geociencias del NOA. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Museo de Ciencias Naturales. Instituto de Bio y Geociencias del NOA; Argentina Fil: Semhan, Romina Valeria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; Argentina Fil: Bulacios Arroyo, Ana Lucia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; Argentina Fil: Schulte, James. Belloit College; Estados Unidos Fil: Paz, Marcos Maximiliano. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; Argentina Fil: Ruiz Monachesi, Mario Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Bio y Geociencias del NOA. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Museo de Ciencias Naturales. Instituto de Bio y Geociencias del NOA; Argentina Fil: Laspiur, Julio Alejandro. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan; Argentina Fil: Aguilar Kirigin, Alvaro Juan. Colección Boliviana de Fauna; Bolivia. Universidad Mayor de San Andrés; Bolivia Fil: Gutierrez Poblete, Ricardo. Universidad Nacional de San Agustín. Facultad de Ciencias Biológicas. Departamento Académico de Biología. Museo de Historia Natural; Perú Fil: Valladares Faundez, Pablo. Universidad de Tarapaca.; Chile Fil: Valdes, José Julian. Universidad Nacional del Nordeste. Facultad de Ciencias Exactas y Naturales y Agrimensura; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina Fil: Portelli, Sabrina Noelia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Bio y Geociencias del NOA. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Museo de Ciencias Naturales. Instituto de Bio y Geociencias del NOA; Argentina Fil: Santa Cruz, Roy. Universidad Nacional de San Agustín. Facultad de Ciencias Biológicas. Departamento Académico de Biología. Museo de Historia Natural; Perú Fil: Aparicio, James. Colección Boliviana de Fauna; Bolivia. Universidad Mayor de San Andrés; Bolivia Fil: García, Noelia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; Argentina Fil: Langstroth, Robeert. Colección Boliviana de Fauna; Bolivia. Universidad Mayor de San Andrés; Bolivia

Species delimitation in Phymaturus has been a difficult task due to the highly conserved morphological and ecological features present in this genus. Almost all species of Phymaturus have been described without DNA data or lacking statistical analyses which makes even more difficult to compare species. Although two molecular phylogenetic studies have been recently published, here we provide the first multilocus phylogenetic reconstruction including all Chilean species, with samples from all type localities and some previously unsampled populations. We also estimate pairwise distances among the Chilean species of Phymaturus (P. vociferator and P. mallimaccii clades) and compare our results with the P. payuniae clade, where previous studies have used multiple lines of evidence. Additionally, we performed univariate and multivariate morphological analyses and skeletal comparisons (clavicle) for the species of the P. vociferator clade. As a result of this integrative approach, we describe a new species.

Body temperature is the most important ecophysiological variable affecting reptiles’ life history. Moreover, thermoregulation in ectotherms implies a struggle to reach preferred temperatures in natural conditions due to the influence of biotic and abiotic factors. Our objective was to evaluate and compare the thermal biology of two syntopic species, Phymaturus extrilidus and Liolaemus parvus, in the Puna region of San Juan, Argentina. We determined body temperature (Tb), micro-environmental temperatures (Ta and Ts) and operative temperatures (Te) in the field. In the laboratory, we measured preferred temperatures (Tpref) and calculated the index of thermoregulatory efficiency (E). Neither body temperatures in the field nor preferred temperatures varied between seasons and sexes. Body temperatures were lower than preferred temperatures for both species. Nevertheless, regardless of the low thermal offer available in habitat, both species did achieve body temperatures higher than operative temperatures during activity. Thermoregulatory effectiveness was moderate in P. extrilidus (E=0.65), while L. parvus presented greater thermoregulatory efficiency (E=0.78). We conclude that under the rigorous climate conditions of the Puna, Phymaturus extrilidus and Liolaemus parvus are able to actively and efficiently thermoregulate, maintaining body temperatures close to the preferred and higher than those of its habitat. Differences in thermal characteristics between Phymaturus extrilidus and Liolaemus parvus are a consequence of differential limitations imposed on each species by the environment and of forces inherent to their life histories. Fil: Gómez Alés, Carlos Rodrigo. Universidad Nacional de San Juan; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Acosta, Juan Carlos. Universidad Nacional de San Juan; Argentina Fil: Laspiur, Julio Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Animals maintain complex associations with a diverse microbiota living in their guts. Our understanding of the ecology of these associations is extremely limited in reptiles. Here, we report an in-depth study into the microbial ecology of gut communities in three syntopic and viviparous lizard species (two omnivores: Liolaemus parvus and Liolaemus ruibali and an herbivore: Phymaturus williamsi). Using 16S rRNA gene sequencing to inventory various bacterial communities, we elucidate four major findings: (i) closely related lizard species harbour distinct gut bacterial microbiota that remain distinguishable in captivity; a considerable portion of gut bacterial diversity (39.1%) in nature overlap with that found on plant material, (ii) captivity changes bacterial community composition, although host-specific communities are retained, (iii) faecal samples are largely representative of the hindgut bacterial community and thus represent acceptable sources for nondestructive sampling, and (iv) lizards born in captivity and separated from their mothers within 24 h shared 34.3% of their gut bacterial diversity with their mothers, suggestive of maternal or environmental transmission.Each of these findings represents the first time such a topic has been investigated in lizard hosts. Taken together, our findings provide a foundation for comparative analyses of the faecal and gastrointestinal microbiota of reptile hosts. Fil: Kohl, Kevin D. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis. Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis; Argentina. Vanderbilt University; Estados Unidos Fil: Brun, Antonio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis. Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis; Argentina Fil: Magallanes Alba, Melisa Eliana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis. Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis; Argentina Fil: Brinkerhoff, Joshua. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis. Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis; Argentina Fil: Laspiur, Julio Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Centro de Investigaciones de la Geosfera y Biosfera. Universidad Nacional de San Juan. Facultad de Ciencias Exactas Físicas y Naturales. Centro de Investigaciones de la Geosfera y Biosfera; Argentina Fil: Acosta, Juan Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Centro de Investigaciones de la Geosfera y Biosfera. Universidad Nacional de San Juan. Facultad de Ciencias Exactas Físicas y Naturales. Centro de Investigaciones de la Geosfera y Biosfera; Argentina Fil: Caviedes Vidal, Enrique Juan Raul. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis. Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis; Argentina Fil: Bordenstein, Seth R.. Vanderbilt University; Estados Unidos

ResumenEl conocimiento de los parámetros tróficos ayuda a comprender la historia natural de la especie, sus requerimientos ecológicos y estrategias involucradas en la búsqueda de alimento. Por ello, describimos y analizamos la dieta de Phymaturus cf. palluma y su variación en términos estacionales e intrapoblacionales. Los ítems fueron identificados en términos cuali-cuantitativos. Se estimó el IRI según el volumen, numerosidad y frecuencia de ocurrencia de los ítems. Se calcularon porcentajes de material vegetal y parásitos nemátodos en tracto digestivo. Phymaturus cf. palluma presenta una alimentación herbívora basada en estructuras vegetales reproductivas y vegetativas. El ítem “flores” fue fundamental, tanto en adultos como juveniles. En adultos macho y hembra, las flores de Adesmia pinnifolia fueron ítems fundamentales, sin embargo, la similitud cualitativa entre machos y hembras fue baja. Los machos presentaron mayor amplitud trófica respecto a hembras. Las estaciones de verano fueron las de mayor diversidad trófica. En cuanto al material vegetativo, hubo diferencias significativas sólo en el consumo de hojas entre estaciones. La competencia estacional por el recurso alimentario sería muy leve debido al amplio espectro de ítems encontrados en las distintas fechas. Phymaturus cf. palluma es un lagarto generalista que forrajea material vegetal en forma activa.AbstractKnowledge of the trophic parameters helps to understand the natural history of the species, their ecological requirements and strategies involved in the food acquisition. Therefore, we describe and analyze the diet of Phymaturus cf. palluma regarding to seasonal and intra populational variation. Items were identified according qualitative and quantitative terms. IRI index was estimated as function of volume, numerosity and frequency of items. Percentages of vegetal material and parasitic nematodes in the digestive tract were calculated. Phymaturus cf. palluma present an herbivorous diet based upon vegetative and reproductive plant structures. In adults and juvenile individuals “flowers” were fundamental item. Overall, in male and female adults, flowers of Adesmia pinnifolia were fundamental; however the qualitative similarity among them was low. Trophic amplitude was higher in males than in females. Summers were the more trophic diversity seasons. Significant differences in the “leaves” consumption between seasons were founded. Seasonal competence for food should be low due to the wide spectrum of items in different periods. Phymaturus cf. palluma is a generalist lizard that feeds vegetal material actively.

While herbivory is a common feeding strategy in a number of vertebrate classes, less than 4% of squamate reptiles feed primarily on plant material. It has been hypothesized that physiological or microbial limitations may constrain the evolution of herbivory in lizards. Herbivorous lizards exhibit adaptations in digestive morphology and function that allow them to better assimilate plant material. However, it is unknown whether these traits are fixed or perhaps phenotypically flexible as a result of diet. Here, we maintained a naturally omnivorous lizard, Liolaemus ruibali, on a mixed diet of 50% insects and 50% plant material, or a plant-rich diet of 90% plant material. We compared parameters of digestive performance, gut morphology and function, and gut microbial community structure between the two groups. We found that lizards fed the plant-rich diet maintained nitrogen balance and exhibited low minimum nitrogen requirements. Additionally, lizards fed the plantrich diet exhibited significantly longer small intestines and larger hindguts, demonstrating that gut morphology is phenotypically flexible. Lizards fed the plant-rich diet harbored small intestinal communities that were more diverse and enriched in Melainabacteria and Oscillospira compared with mixed diet-fed lizards. Additionally, the relative abundance of sulfate-reducing bacteria in the small intestine significantly correlated with whole-animal fiber digestibility. Thus, we suggest that physiological and microbial limitations do not sensu stricto constrain the evolution of herbivory in lizards. Rather, ecological context and fitness consequences may be more important in driving the evolution of this feeding strategy. Fil: Kohl, Kevin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis. Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis; Argentina. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Departamento de Bioquímica y Ciencias Biológicas; Argentina. Vanderbilt University; Estados Unidos Fil: Brun, Antonio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis. Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis; Argentina. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Departamento de Bioquímica y Ciencias Biológicas; Argentina Fil: Magallanes Alba, Melisa Eliana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis. Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis; Argentina. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Departamento de Bioquímica y Ciencias Biológicas; Argentina Fil: Brinkerhoff, Joshua. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis. Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis; Argentina. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Departamento de Bioquímica y Ciencias Biológicas; Argentina Fil: Laspiur, Julio Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan; Argentina. Universidad Nacional de San Juan. Facultad de Ciencias Exactas Físicas y Naturales. Departamento de Biología; Argentina Fil: Acosta, Juan Carlos. Universidad Nacional de San Juan. Facultad de Ciencias Exactas Físicas y Naturales. Departamento de Biología; Argentina Fil: Bordenstein, Seth R.. Vanderbilt University; Estados Unidos Fil: Caviedes Vidal, Enrique Juan Raul. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis. Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis; Argentina. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Departamento de Bioquímica y Ciencias Biológicas; Argentina

Oplurus bibronii was a species described more than 160 years ago from the highlands of Ovalle, Chile. The species was earlier synonymized with Phymaturus palluma and since then its taxonomic status has not been re-examined. In February of 2011, we were successful in capturing specimens of Phymaturus in the highlands of Ovalle and additionally we examined high quality digital pictures of the type series of O. bibronii. Our analysis shows that the type series is composed of two different species, one of which overlaps their diagnostic characters with the characters of the specimens collected in the highlands of Ovalle, and therefore they correspond to Phymaturus bibronii (new combination). In addition, our review of the holotype, and some paratypes and topotypes of the recently described P. paihuanense shows that this is a junior synonym of P. bibronii.

As a result of several field trips and studies of collections of Phymaturus samples from Andean areas of central western Argentina (San Juan province), we discovered two populations that exhibit a particular character combination not seen in other species formally recognized in the literature. Based on a detailed analysis of an extended list of morphological characters (93), including scalation, color pattern, gular and nuchal folds, precloacal pores, and morphometric data, we conclude that these populations represent independent lineages that deserve to be considered as new species. According to the most recent revision of the genus and considering the descriptions made in another recent contribution, the taxonomic composition of the genus was increased to 38 species. In this study we provide the formal description of two additional new taxa, including their diagnosis and detailed comparisons with other members of their species group. The two new species belong to the palluma group, and can be assigned to the Puna subclade because they present the typical dorsal "spray" pattern. Other characters described in this study suggest their close phylogenetic relationship with other species of this subclade inhabiting the southern Puna region of Argentina, such as Phymaturus punae. Within the Puna subclade, Phymaturus aguanegra sp. nov. differs from all other members (P. antofagastensis, P. denotatus, P. laurenti, P punae, P extrilidus, P mallimaccii and P paihuanense) exhibiting the following combination of diagnostic characters: a complete melanism over the dorsum of neck, the presence of enlarged scales at the base of tail in males, having strongly keeled tarsal scales, lacking enlarged scales on the anterior margin of the antehumeral fold and centre of chest, females without flank coloration, a vertebral dark gray stripe usually present on the dorsum, females exhibiting a tricolor dorsal pattern, with two types of brown and scattered ferriferous oxide spots, and the absence of a scapular spot. Phymaturus williamsi sp. nov. differs from all other members of the Puna clade because: exhibits an "aggregate" dorsal pattern, unlike the homogeneous spray of most Puna species, lacks enlarged scales on the anterior margin of the antehumeral fold and in the centre of chest, flank coloration in females is absent, females of Phymaturus williamsi sp. nov. lack white transversal stripes on the dorsal pattern, preocular scale in contact with canthal scale in Phymaturus williamsi sp. nov., rostral scale can be divided in Phymaturus williamsi sp. nov. and shows the largest number of scales counted around midbody within the Puna subclade (x= 213.4; 186-235).

Albinism has been widely reported for diverse group of vertebrates. However, scoliosis is a rare abnormality. In this work, the first record of partial albinism and scoliosis case in tadpole of the frog Odontophrynus occidentalis is being presented. The individual was captured in Quebrada de las Flores, Sierra Pie de Palo, Caucete Department, San Juan Province, Argentina.

In this paper we describe a new species of the Leiosaurus genus from central-western Argentina. This new taxon presents remarkable differences regarding the lepidosis and coloration pattern compared to the other species of the genus: L. catamarcensis, L. paronae and L. bellii. The dorsal coloration pattern is unique and is characterized by dorsal markings similar to the colour design of some felines like the jaguar. This new species inhabits the highlands of central-western Argentina where steppe bunch grasses with low plant formation and low spiny shrubs prevail. However, little is known of its biology as with the other species of the genus Leiosaurus. The discovery of this new taxon is significant, because it has been one hundred years since the last description of a new species of these taxa.

In Argentina not antecedents regarding to lizards vocalization studies exist. This work to seeks to highlight in two leiosaurid species (Leiosaurus catamarcensis and Pristidactylus scapulatus) the vocalization characteristics in order to evaluate potentially valid differences for systematic use. The vocalizations were registered in temperature controlled conditions and simulating aggressive encounters. The observed repertoire consists in two, warning (ADV) and attack (AT) vocalization components, different among themselves due to vocalization temporary length. L. catamarcensis and P. scapulatus vocalize in a same frequency rank, regardless to the vocalization type. Besides we find that the L. catamarcensis vocalizations were more prolongest than P. scapulatus. En Argentina no existen antecedentes respecto al estudio de las vocalizaciones en lagartos. Este trabajo pretende dar a conocer las características de la vocalización de dos especies de leiosauridos (Leiosaurus catamarcensis y Pristidactylus scapulatus) con el fin de detectar y evaluar diferencias potencialmente válidas para el uso en sistemática. Las vocalizaciones fueron registradas en condiciones controladas de temperatura y simulando encuentros agresivos. El repertorio observado consistió de dos componentes de vocalización, una de advertencia (ADV) y otra de ataque (AT), diferentes por la longitud temporal de la vocalización. L. catamarcensis y P. scapulatus vocalizan en un mismo rango de frecuencia, independientemente del tipo de vocalización. Además encontramos que las vocalizaciones en L. catamarcensis son más prolongadas que en P. scapulatus.

En Argentina no existen antecedentes respecto al estudio de las vocalizaciones en lagartos. Este trabajo pretende dar a conocer las características de la vocalización de dos especies de leiosauridos (Leiosaurus catamarcensis y Pristidactylus scapulatus) con el fin de detectar y evaluar diferencias potencialmente válidas para el uso en sistemática. Las vocalizaciones fueron registradas en condiciones controladas de temperatura y simulando encuentros agresivos. El repertorio observado consistió de dos componentes de vocalización, una de advertencia (ADV) y otra de ataque (AT), diferentes por la longitud temporal de la vocalización. L. catamarcensis y P. scapulatus vocalizan en un mismo rango de frecuencia, independientemente del tipo de vocalización. Además encontramos que las vocalizaciones en L. catamarcensis son más prolongadas que en P. scapulatus., In Argentina not antecedents regarding to lizards vocalization studies exist. This work to seeks to highlight in two leiosaurid species (Leiosaurus catamarcensis and Pristidactylus scapulatus) the vocalization characteristics in order to evaluate potentially valid differences for systematic use. The vocalizations were registered in temperature controlled conditions and simulating aggressive encounters. The observed repertoire consists in two, warning (ADV) and attack (AT) vocalization components, different among themselves due to vocalization temporary length. L. catamarcensis and P. scapulatus vocalize in a same frequency rank, regardless to the vocalization type. Besides we find that the L. catamarcensis vocalizations were more prolongest than P. scapulatus.

Fil: Lobo Gaviola, Fernando Jose. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Salta. Instituto de Bio y Geociencias del Noroeste Argentino; Argentina

Oplurus bibronii was a species described more than 160 years ago from the highlands of Ovalle, Chile. The species was earlier synonymized with Phymaturus palluma and since then its taxonomic status has not been re-examined. In February of 2011, we were successful in capturing specimens of Phymaturus in the highlands of Ovalle and additionally we examined high quality digital pictures of the type series of O. bibronii. Our analysis shows that the type series is composed of two different species, one of which overlaps their diagnostic characters with the characters of the specimens collected in the highlands of Ovalle, and therefore they correspond to Phymaturus bibronii (new combination). In addition, our review of the holotype, and some paratypes and topotypes of the recently described P. paihuanense shows that this is a junior synonym of P. bibronii.