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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. [ABSTRACT FROM AUTHOR]

The thermal quality of the habitat is key for the regulation of body temperature in terrestrial ectotherms and, therefore, permits them to carry out their fundamental biological activities. In thermally heterogeneous environments, ectotherms might follow different behavioral or physiological strategies to maintain their body temperature within biologically adequate boundaries, for which they depend on microhabitat selection. These aspects are, thus, relevant in the context of habitat degradation and land‐use change. In this study, we characterized the thermal ecology of three lizard species (genus Xantusia) that differ in microhabitat use along the Baja California peninsula, Mexico. We made three predictions: (1) the three species will follow different thermoregulatory strategies according to habitat thermal quality; (2) the thermal requirements and tolerances of these species will match the environmental or microenvironmental thermal conditions; and (3) due to their habitat and range restriction, the species studied will be highly vulnerable to climate change. Our results indicate the existence of thermoregulatory mechanisms in Xantusia to face thermal heterogeneity, including behavioral thermoregulation by choosing different microhabitats, shifts in activity periods, and adaptation to particular high thermal quality microhabitats. Furthermore, despite their association to specific microhabitats and specialized physiology, the studied species will not be adversely affected by climate change, as the increased microenvironmental temperatures will lead to a higher habitat thermal quality and lower costs of thermoregulation. However, we do not discard other indirect adverse effects of climate change not considered in this study. Research Highlights: Microhabitats provide studied species favorable temperatures in thermally heterogeneous habitats.These species have thermal strategies to face thermal fluctuation.Our approach suggests an increase in the habitat thermal quality for studied species. [ABSTRACT FROM AUTHOR]

Aim: Climatic variation has long been regarded as a primary source of morphological variation. However, there is mixed support for the adherence of reptiles to ecogeographical hypotheses, such as Bergmann's rule (body size decreases with temperature) and Allen's rule (limb length increases with temperature). We quantified body and limb morphology among the diverse Australian gecko fauna (4 families, 30 genera, 226 of the 231 described species) to investigate environmental correlates of morphological variation in this radiation. Location: Australia. Major taxa studied: Geckos (Squamata: Gekkota; the families Gekkonidae, Carphodactylidae, Diplodactylidae and Pygopodidae). Methods: We measured 20 external features of ethanol‐preserved museum specimens. We investigated whether principal component axes of morphology were correlated with three key environmental variables, and the microhabitat occupied by each species. Results: Morphology varied greatly among Australian gecko families and genera, although there was a strong phylogenetic signal in morphology. After accounting for phylogeny, morphology was correlated with a species' microhabitat use. Saxicolous species and species with variable microhabitat requirements (i.e., generalists) had larger body dimensions than terrestrial species. Saxicolous species also had longer proportional forelimbs and hindlimbs than terrestrial species. Main conclusions: Our results highlight the importance of phylogeny and microhabitat use in shaping the morphology of Australian geckos. We find little evidence that Australian geckos adhere to Bergmann's rule or Allen's rule, suggesting that these ecogeographical hypotheses provide limited insight into the adaptive potential of lizard species to altered environmental conditions. [ABSTRACT FROM AUTHOR]

The known diversity of the genus Liolaemus continues to increase, principally due to its great degree of endemism, the increasing number of researchers working on it, and advances in the taxonomic and phylogenetic knowledge of the genus. This diversity positions Liolaemus as the second most species-rich tetrapod genus. The present work adds to evidence for the great diversity of Liolaemus through the description of two new species, endemic to saline environments in the Argentinian Puna. Both species are members of the Liolaemus montanus group within the subgenus Eulaemus. To determine the taxonomic status of these lizards, we used integrative taxonomy as a tool, incorporating phylogenetic, morphological, and molecular genetic evidence, as well as the anatomy of hemipenes, statistical morphological analysis, and ecological characteristics. Our analyses supported the conclusion that both sampled populations of lizards are species new to science. One of these is found along the margins of the Antofalla salt flats in the Catamarca Province and the Hombre Muerto salt flats in the Salta Province. The other new species inhabits saline habitats vegetated by Lycium humile, principally between the salt crusts of the Antofalla salt flats. Both species are small to medium sized and can be distinguished from all other species of the L. montanus group by unique combinations of morphological characters, primarily pholidosis and dorsal and ventral colour patterns. [ABSTRACT FROM AUTHOR]

Some form of regeneration occurs in all lifeforms and extends from single‐cell organisms to humans. The degree to which regenerative ability is distributed across different taxa, however, is harder to ascertain given the potential for phylogenetic constraint or inertia, and adaptive processes to shape this pattern. Here, we examine the phylogenetic history of regeneration in two groups where the trait has been well‐studied: arthropods and reptiles. Because autotomy is often present alongside regeneration in these groups, we performed ancestral state reconstructions for both traits to more precisely assess the timing of their origins and the degree to which these traits coevolve. Using an ancestral trait reconstruction, we find that autotomy and regeneration were present at the base of the arthropod and reptile trees. We also find that when autotomy is lost it does not re‐evolve easily. Lastly, we find that the distribution of regeneration is intimately connected to autotomy with the association being stronger in reptiles than in arthropods. Although these patterns suggest that decoupling autotomy and regeneration at a broad phylogenetic scale may be difficult, the available data provides useful insight into their entanglement. Ultimately, our reconstructions provide the important groundwork to explore how selection may have played a role during the loss of regeneration in specific lineages. Research Highlights: Ancestral state reconstruction demonstrates that autotomy and regeneration were present in the basal ancestors of arthropods and squamate reptiles and that the distribution of regeneration is intimately connected to autotomy. [ABSTRACT FROM AUTHOR]

Nematodes are little known in the Argentine herpetofauna. In order to increase and contribute to the knowledge of parasitism in reptiles, we studied nematodes found in three species of lizards (Aurivela longicauda, Liolaemus darwinii, and L. riojanus) and one species of snake (Philodryas trilineata) from the Monte desert of center-west Argentina. We registered generalist nematodes commonly found in reptiles, belonging to three taxa: Physaloptera sp. (larvae), Physaloptera retusa (adults) (Physalopteridae) and Parapharyngodon riojensis (Pharyngodonidae) (adults). Liolaemus darwinii had the lowest prevalence of Physaloptera sp. (larvae) (30%) and a mean intensity of 1.3±0.4 (1-2). The lizard A. longicauda had the highest parasitic diversity (2 taxa) with prevalence (50%) and mean intensity (4±3.5) of Physaloptera retusa (adults), also with prevalence (12.5%) and mean intensity (20±0) of Parapharyngodon riojensis (adults). Due to the low number of studied specimens, precise conclusions cannot be drawn for Liolaemus riojanus (n = 2) and P. trilineata (n = 1). However, because the hosts were previously fixed, the results probably may do not represent real infection patterns. The four reptile species correspond to new host records from Argentina, and the information provided contributes to the knowledge of endoparasitism in reptiles of the Argentine Monte region. [ABSTRACT FROM AUTHOR]

Reproductive physiology is influenced by environmental pressures, particularly in ectothermic species living in harsh climatic conditions. Studying the period of time in which males exhibit semen availability and their sperm traits constitutes a powerful tool to evaluate the fertility potential of males because sperm size and sperm velocity have been proposed as determinants in fertilization success. Pristidactylus achalensis is a lizard endemic to the highest mountain areas in Central Argentina and shows a pattern of seasonal activity. Here, we study the period of time when males possess sperm during the active season and characterize the spermatozoa based on sperm morphometric and dynamic traits among males and within ejaculate. Males possess sperm in their ejaculates only during the spring months of the active season, suggesting that reproductive activity is restricted to this time. Spermatozoa of Pristidactylus achalensis show intra-specific variation in sperm traits among males and within ejaculate, suggesting different reproductive potential among males. Since this species only occupies the highest areas of the mountains and is categorized as vulnerable, basic information about reproduction and sperm physiology could be useful for potential population conservation strategies. [ABSTRACT FROM AUTHOR]

The genus Liolaemus includes 268 species, classified in two subgenera, Eulaemus and Liolaemus sensu stricto. The latter is formed by 12 monophyletic groups; one of them being the Liolaemus elongatus group, distributed in South America. We studied the biogeographic history of the L. elongatus group. We obtained a phylogenetic hypothesis recovering five main clades: the L. punmahuida, L. elongatus sensu stricto, L. kriegi, L. petrophilus and L. capillitas clades. Based on that hypothesis we obtained a time calibrated tree. The ancestral ranges were estimated applying three methodologies: DEC, DEC+j (using predefined areas) and GEM (using explicit geographical data). Our results show that the ancestral area of the L. elongatus group was located in central Argentina, and its divergence began around 11.5 Mya. From here, a combination of events (founder events and/or vicariances) led the species to their current distribution. Despite their differences, DEC+j and GEM show congruent results. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Zoology is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective: Assessments of the medial olivocochlear reflex (MOCR) may have clinical utility. The MOCR is measured using contralateral inhibition of otoacoustic emissions but concurrent activation of the middle ear muscle reflex (MEMR) confounds test interpretation. MEMR activation can be detected using the change in ear-canal stimulus amplitude without versus with an MOCR elicitor. This study provides a description of how critical differences in ear-canal stimulus amplitude can be established. Design: Clicks were presented in right ears without and with a contralateral MOCR elicitor. Ear-canal stimulus amplitudes were measured. Two measurements without an elicitor were used to develop critical differences. MEMR activation was considered present if the difference in ear-canal stimulus amplitude without versus with an elicitor exceeded the critical difference. Study sample: Forty-six normal-hearing adults (mean age = 23.4 years, 35 females) participated, with data from 44 participants included in the final analysis. Results: Two participants exceeded the 95% critical difference. The 80, 90 and 99% critical differences are also reported for reference. Conclusions: Results suggest that the contralateral elicitor can evoke the MEMR in a small number of participants. The methods described in this paper can be used for developing equipment- and clinicspecific critical differences for detecting MEMR activation. [ABSTRACT FROM AUTHOR]

Copyright of Cuadernos de Herpetología is the property of Asociacion Herpetologica Argentina and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Cuadernos de Herpetología is the property of Asociacion Herpetologica Argentina and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Cuadernos de Herpetología is the property of Asociacion Herpetologica Argentina and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Zoologica Lilloana is the property of Fundacion Miguel Lillo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Bergmann's rule describes the macroecological pattern of increasing body size in response to higher latitudes and elevations. This pattern is extensively documented in endothermic vertebrates, within and among species; however, studies involving ectotherms are less common and suggest no consistent pattern for amphibians and reptiles. Moreover, adaptive traits, such as epidermal features like scales, have not been widely examined in conjunction with Bergmann's rule, even though these traits affect physiological processes, such as thermoregulation, which are hypothesized as underlying mechanisms for the pattern. Here, we investigate how scale characters correlate with elevation among 122 New World pitviper species, representing 15 genera. We found a contra‐Bergmann's pattern, where body size is smaller at higher elevations. This pattern was mainly driven by the presence of small‐bodied clades at high elevations and large‐bodied clades at low elevations, emphasizing the importance of taxonomic scope in studying macroecological patterns. Within a subset of speciose clades, we found that only Crotalus demonstrated a significant negative relationship between body size and elevation, perhaps because of its wide elevational range. In addition, we found a positive correlation between scale counts and body size but no independent effect of elevation on scale numbers. Our study increases our knowledge of Bergmann's rule in reptiles by specifically examining characters of squamation and suggests a need to reexamine macroecological patterns for this group. [ABSTRACT FROM AUTHOR]

Evolution is rapidly gaining attention as an important driver of ecological process. Yet, evolution via sexual selection has generally been omitted from this emerging synthesis. Our goal in this paper is to illustrate causative links by which sexually selected traits affect fundamental ecological interactions and processes. We summarize evidence, primarily from vertebrate studies under field conditions, which shows: sexually selected traits have ecological effects; and that their evolution has diverse influences on ecological systems. We conclude with a brief discussion of future research directions to encourage study of sexual selection from a more integrative and eco-evolutionary perspective. [ABSTRACT FROM AUTHOR]

Habitat use and thermal biology are closely related, because thermal microclimates vary spatially. The use of habitat and microhabitat by different species influences many of their traits, such as their physiology, and may, therefore exert a direct effect on survival. Ectothermal animals, such as lizards, are affected by thermal and biophysical environments they inhabit, and the particular use of a given substrate reflects an overlap between thermally adequate microhabitats, and behavioral preferences. By exploiting certain microhabitats and avoiding others, many lizards tend to maintain their body temperature within a range that allows maximum performance. Here, we evaluate how two syntopic species of lizards, Liolaemus pacha and L. ramirezae, use substrates with different exposure to solar radiation. Our hypothesis is that L. pacha uses both soil and rock substrates indistinctly, due to being a generalist species, whereas L. ramirezae uses the rock substrate more frequently, due to its saxicolous habits. We expect temperatures to be different both in substrates, and in different exposures, and thermal characteristics of each species to condition their use. For example, because the body temperature range of L. pacha is wider, we predict that substrate use will be wider. A pre-established 100x75 m area was monitored during four Austral springs and summers between 2011 and 2015, in Los Cardones, Amaicha del Valle, Tucumán, Argentina. Species ' substrate where the lizard was found (soil or rock), and exposure to solar radiation: sun, filtered shade or full shade was recorded. After capture, lizard body temperature (Tb), substrate temperature (Ts), and air temperature (Ta) were recorded in the place of the first observation of the lizard. Obtained results show that L. pacha and L. ramirezae had a more persistent use of the rock than the soil substrate, thus considering them saxicolous species. Further, they were frequently observed exposed to direct sunlight. Average body temperature was higher than environmental temperature (Ts and Ta), and significantly different in each exposure type (sun, filtered shade and full shade), and in both substrates (rock and soil). Differential use of substrate and the relationship between body temperature and microhabitat temperatures suggests that L. pacha and L. ramirezae are "active thermoregulators", using both substrate surfaces and solar radiation as heat sources. [ABSTRACT FROM AUTHOR]

Formerly Cnemidophorus was thought to be the most speciose genus of Teiidae. This genus comprised four morphological groups that were later defined as four different genera, Ameivula, Aurivela, Cnemidophorus and Contomastix. The last appears as paraphyletic in a recent phylogenetic reconstruction based on morphology, but monophyletic in a reconstruction using molecular characters. Six species are allocated to Contomastix. One of them, C. lacertoides, having an extensive and disjunct geographic distribution in Argentina, Uruguay and Brazil. Preliminary analyses revealed morphological differences among its populations, suggesting that it is actually a complex of species. Here, we describe a new species corresponding to the Argentinian populations hitherto regarded as C. lacertoides, by integrating morphological and molecular evidence. Furthermore, we demonstrate that the presence of notched proximal margin of the tongue is a character that defines the genus Contomastix. [ABSTRACT FROM AUTHOR]

Copyright of Cuadernos de Herpetología is the property of Asociacion Herpetologica Argentina and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Zoology is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: Phymaturus is a clade of lizards that occurs at moderate to high elevations in western Argentina and the adjacent central region of Chile, as well as in various volcanic plateaus of the Patagonian region of Argentina. This genus had previously been divided into two groups: the patagonicus and the palluma groups. In this study, we analyzed relationships within the patagonicus group. The data set was built for 23 species plus nine other terminal taxa of undetermined taxonomic status. In total, 10,631 bp (ND4, Cytb, 12S, COI, five protein coding nuclear genes and seven anonymous nuclear loci) and 254 morphological characters were analyzed in a combined data set for 35 ingroup taxa and nine outgroups. We also ran separate DNA sequence and morphological data sets. We identified four main clades, and revealed congruencies and incongruences with previous studies. The indistinctus clade is recovered as the most basal within the patagonicus group in the strict parsimony analysis, while the somuncurensis clade is the most basal under Bayesian inference. The previously recovered calcogaster clade resulted paraphyletic in both analyses and part of their species are included in a redefined somuncurensis clade. We found low support at basal nodes provoked in part by contradictory evidence shown by rogue taxa. We show the phylogenetic information given by each partition/marker and how they contribute to relationships found in the total evidence analysis. We discuss the phylogenetic position of Phymaturus manuelae, Phymaturus tenebrosus, and Phymaturus patagonicus. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Zoology is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: Solar radiation is an important driver of animal coloration, not only because of the effects of coloration on body temperature but also because coloration may protect from the deleterious effects of UV radiation. Indeed, dark coloration may protect from UV, but may increase the risk of overheating. In addition, the effect of coloration on thermoregulation should change with egg size, as smaller eggs have higher surface‐volume ratios and greater convective coefficients than larger eggs, so that small eggs can dissipate heat quickly. We tested whether the reflectance of eggshells, egg spottiness, and egg size of the ground‐nesting Kentish plover Charadrius alexandrinus is affected by maximum ambient temperature and solar radiation at breeding sites. We measured reflectance, both in the UV and human visible spectrum, spottiness, and egg size in photographs from a museum collection of plover eggshells. Eggshells of lower reflectance (darker) were found at higher latitudes. However, in southern localities where solar radiation is very high, eggshells are also of dark coloration. Eggshell coloration had no significant relationship with ambient temperature. Spotiness was site‐specific. Small eggs tended to be light‐colored. Thermal constraints may drive the observed spatial variation in eggshell coloration, which may be lighter in lower latitudes to diminish the risk of overheating as a result of higher levels of solar radiation. However, in southern localities with very high levels of UV radiation, eggshells are of dark coloration likely to protect embryos from more intense UV radiation. Egg size exhibited variation in relation to coloration, likely through the effect of surface area‐to‐volume ratios on overheating and cooling rates of eggs. Therefore, differential effects of solar radiation on functions of coloration and size of eggshells may shape latitudinal variations in egg appearance in the Kentish plover. [ABSTRACT FROM AUTHOR]

Body temperatures in ectotherms are strongly affected by their thermal environment. Ectotherms respond to variation in the thermal environment either by modification of behavioural thermoregulation to maintain their optimal body temperature or by shifting their optimal body temperature. In this study, the body temperatures of males of three populations of spotted snow skinks, Niveoscincus ocellatus , living along an altitudinal gradient (low, mid, and high altitude) were studied in the field and laboratory in spring, summer, and autumn, representing the full activity period of this species. The environmental variation across both sites and seasons affected their field active body temperatures. At the low and mid altitude, N. ocellatus had a higher mean body temperature than at the high altitude. Animals achieved their thermal preference at the low and mid altitude sites in all seasons. At the high altitude, however, N. ocellatus struggled to reach its preferred body temperatures, especially in autumn. The lower body temperature at the high-altitude site is likely due to limited thermal opportunity and/or an effect of avoiding the costs associated with increased intensity of basking. This study investigated the body temperatures of spotted snow skinks living along an altitudinal gradient over a full activity period of this species. The environmental variation across sites and seasons affected their body temperatures, and they achieved their thermal preference with the exception at high altitude. Thermoregulatory behaviour acts as a potential buffer to overcome changes in environmental conditions. Photo by Erik Wapstra. [ABSTRACT FROM AUTHOR]

Copyright of Revista Mexicana de Biodiversidad is the property of Universidad Nacional Autonoma de Mexico, Instituto de Biologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: Variations in species morphology and life‐history traits strongly correlate with geographic and climatic characteristics. Most studies on morphological variations in animals focus on ectotherms distributed on a large geographic scale across latitudinal and/or altitudinal gradient. However, the morphological variations of spiders living in the same habitats across different seasons have not been reported. In this study, we used the wolf spider, Pardosa astrigera, as a model to determine seasonal differences in adult body size, melanism, fecundity, and egg diameter both in the overwintering and the first generation for 2010 and 2016. The results showed that in 2010, both females and males of the overwintering generation were significantly darker than the first generation. Moreover, the overwintering females were markedly larger and produced more and bigger eggs than the first generation in both 2010 and 2016. Considering the overwintering P. astrigera experiencing low temperature and/or desiccation stress, these results suggest that substantially darker and larger body of the overwintering generation is adaptive to adverse conditions. [ABSTRACT FROM AUTHOR]

Protected areas have been established historically in residual places where the potential for extractive uses is low, implying that places at risk are usually under-protected. Argentina is no exception, with few protected areas established in productive regions that are prone to conversion. Here, using reptiles as a study group and considering the most important human threats in north-western Argentina, we estimated priority conservation areas where we expect species to persist in the face of climate change and land conversion. Protected areas cover no more than 9% of the study region, but represent less than 15% of reptile distributions. There are great opportunities for improving the conservation status in the region by protecting only 8% more of north-western Argentina, with the level of species protection inside the protected area network increasing almost four-fold, reaching 43% of species distributions on average and 59% of the distributions of threatened reptiles. Fortunately, the highest diversity of reptiles in the region does not match the places targeted for agriculture expansion. Our findings suggest that future prioritization schemes should embrace other groups that are especially diverse in the Chaco ecoregion, which overlaps with our study area. [ABSTRACT FROM PUBLISHER]

We present herein a list of amphibians and reptiles from La Picadita, Formosa, Argentina (26°02'16" S, 59°09'26" W), in the Humid Chaco ecoregion, recorded between November 2013 and February 2014. Specimens were captured with 25 drift fence-pitfall traps set in forests, and active searches in flooded areas ("esteros"). We recorded 6 lizard species, 9 snakes, 2 amphisbaenians, and 29 amphibians, totalizing 46 species. Rarefaction curves suggest that our sampling effort was appropriate for amphibians, but more sampling is needed for lizards and snakes. The use of pitfall traps combined with active searches was a useful method to capture elusive and cryptic species in sampled environments. This methodology is suggested in order to obtain full species inventories, and optimize available resources. [ABSTRACT FROM AUTHOR]

Liolaemus chiliensis, a widely distributed species in Chile, is unique in vertebrates because it presents populations with diploid (2n), triploid (3n) and mosaic (2n/3n) females, and with diploid and mosaic males whose meiosis produces reduced (n) and unreduced (2n) euploid gametes. With the aim of evaluating evolutionary consequences of polyploidy, we analyzed the morphological variability of 103 adults of L. chiliensis from separated geographic areas using both traditional and geometric morphometry in order to visualize shape and size differences in individuals with different ploidy. The results indicated that Liolaemus chiliensis is morphologically variable; a significant effect was observed for the interaction term of the three factors tested: sex, ploidy and locality. From the analysis, females exhibited higher values of axilla groin distance than males. There were also morphological differences in mosaic and triploid organisms with respect to the sympatric and allopatric diploids in the dorsal shape of the head, and the presence of intermediate phenotypes of triploids and mosaic lizards with sympatric males and females associated with the axilla groin distance. Results showed that there are morphological differences between polyploid and diploid organisms with both traditional and geometric approaches, suggesting evolutionary trend to differentiation; future research is needed to assess the underlying ecological and genetic mechanisms related to this phenomenon. [ABSTRACT FROM AUTHOR]

Two hypotheses have prevailed to explain the evolution of viviparity in reptiles: the first proposed that viviparity evolved in response to cold-climates because the possibility of pregnant females to thermoregulate at higher temperatures than embryos could experience in a nest in nature. The second hypothesis posits that the advantage of viviparity is based on the possibility of females to maintain stable body temperatures during development, enhancing offspring fitness. With the aim to contribute to understanding the origins of viviparity in reptiles, we experimentally subjected pregnant females of the austral lizard Liolaemus sarmientoi to two temperature treatments until parturition: one that simulated environmental temperatures for a potential nest (17-25 °C) and another that allowed females to thermoregulate at their preferred body temperature (17-45 °C). Then, we analysed newborn body conditions and their locomotor performance to estimate their fitness. In addition, we measured the body temperature in the field and the preferred temperature in the laboratory of pregnant and non-pregnant females. Pregnant females thermoregulated to achieve higher temperatures than the environmental temperatures, and also thermoregulated within a narrower range than non-pregnant females. This could have allowed embryos to develop in higher and more stable temperatures than they would experience in a nest in nature. Thus, offspring developed at the female preferred temperature showed greater fitness and were born earlier in the season than those developed at lower environmental temperatures. Herein, we show that results are in agreement with the two hypotheses of the origin of viviparity for one of the southernmost lizards of the world. [ABSTRACT FROM AUTHOR]

Copyright of Revista Brasileira de Agricultura Irrigada - RBAI is the property of Revista Brasileira de Agricultura Irrigada - RBAI and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Dry Chaco ecoregion is one of the largest remnants of dry forest in Latin America and has a very diverse herpetofauna. However, further studies are required for a deep knowledge of its composition and structure. Our objective was to perform an inventory of the herpetofauna in two natural areas of Dry Chaco of Santiago del Estero: Caburé Sur and Parque Provincial Copo. In the two protected areas we recorded 21 and 25 species of anurans and reptiles, respectively. According to the last Argentinean conservation assessment we found one threatened and five vulnerable species of reptiles in both protected areas. The inventory revealed that herpetofauna of the two protected areas of Santiago del Estero contains about 60% of the Dry Chaco herpetofauna. We report the presence of three new species for Santiago del Estero: Kentropyx viridistriga, Teius oculatus and Stenocercus doellojuradoi. We provide new information for future research and conservation actions on this ecoregion. [ABSTRACT FROM AUTHOR]

Squamates form a substantial part of the present-day South American herpetofauna, and their fossils constitute an indispensable evidence for understanding the origin and evolution of the main taxa. Squamates are relatively common in Miocene localities of Patagonia, especially in levels of the late early Miocene Santa Cruz Formation. In this contribution, remains of the three species of the extinct iguanid Erichosaurus Ameghino 1899 (E. diminutus, E. bombimaxilla and E. debilis) are redescribed, and new squamate specimens are reported for first time. The genus Erichosaurus is considered invalid. Erichosaurus debilis, E. diminutus and a new specimen are recognized as indeterminate species of the extant polichrotine Pristidactylus, whereas E. bombimaxilla remains as an indeterminate iguanid. Snakes are represented by an indeterminate colubrid. All these specimens, together with a tupinambine teiid previously described for the same formation, represent the southernmost fossil record of squamates in South America and indicate the occurrence of the iguanid Pristidactylus, the teiid Tupinambis and the colubrid snakes south to their present distribution as back as during the early Miocene. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Herpetology is the property of Society for the Study of Amphibians & Reptiles and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Herpetology is the property of Society for the Study of Amphibians & Reptiles and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

By analysing size and shape separately, geometric morphometric methods (GM) are a powerful tool to evaluate morphological differences within and between taxa. In this work, we used GM to investigate whether lizards of the Liolaemus melanops complex differ in shape and size. Specifically, we analysed head shape and size variation to quantify intraspecific sexual dimorphism and interspecific differences. We found sexual dimorphism in six of the seven investigated species (L. canqueli, L. dumerili, L. goetschi, L. martorii, L. melanops and L. morenoi). Five species (L. canqueli, L. casamiquelai, L. martorii, L. melanops and L. morenoi) were distinct in shape and size, whereas L. goetschi and L. dumerili were indiscernible from each other. This work illustrates the value of GM to study morphological variation in lizards, suggesting that similar studies would be valuable for testing species boundaries in other groups of Liolaemus. [ABSTRACT FROM AUTHOR]

Copyright of Revista Mexicana de Biodiversidad is the property of Universidad Nacional Autonoma de Mexico, Instituto de Biologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Global climate change affects the distributions of ectotherms and may be the cause of several conservation problems, such as great displacement of climatic suitable spaces for species and, consequently, important reductions of the extent of liveable places, threatening the existence of many of them. Species exposure (and hence vulnerability) to global climate change is linked to features of their climatic niches (such as the relative position of the inhabited localities of each species in the climatic space), and therefore to characteristics of their geographic ranges (such as the extent of the distributions or altitudinal range inhabited by the species). In order to analyze the pattern of response of Argentine reptiles to global climate change, we ran phylogenetic generalized least squares models using species exposure to global climate change as a response variable, and (i) niche properties (breadth and position of the species in the climate space) and (ii) general features of the distribution of species (maximum latitude, altitudinal range, maximum elevation, distributional range and proximity to the most important dispersal barrier) as predictors. Our results suggest that the best way to explain climate change exposure is by combining breadth and position of climatic niche of the species or combining geographic features that are indicators of both niche characteristics. Our best model shows that in our study area, species with the narrowest distributional ranges that also inhabit the highest elevations are the most exposed to the effects of global climate change. In this sense, reptile species from Yungas, Puna and Andes ecoregions could be especially vulnerable to the effects of climate change. We believe that these types of models may represent an interesting tool for determining species and places particularly threatened by the effects of global climate change, which should be strongly considered in conservation planning. [ABSTRACT FROM AUTHOR]

The body temperature of ectotherms depends on the environmental temperatures and behavioral adjustments, but morphology may also have an effect. For example, in colder environments, animals tend to be larger and to show higher thermal inertia, as proposed by Bergmann's rule and the heat balance hypothesis (HBH). Additionally, dark coloration increases solar radiation absorption and should accelerate heat gain (thermal melanism hypothesis, TMH). We tested Bergmann's rule, the HBH and the TMH within the Liolaemus goetschi lizard clade, which shows variability in body size and melanic coloration. We measured heating and cooling rates of live and euthanized animals, and tested how morphology and color affect these rates. Live organisms showless variable and faster heating rates compared with cooling rates, suggesting behavioral and/or physiological adjustments. Our results support Bergmann's rule and the HBH, as larger species show slower heating and cooling rates. However, we did not find a clear pattern to support the TMH. The influence of dorsal melanism on heating by radiation was masked by the body size effect in live animals, and results from euthanized individuals also showed no clear effects of melanism on heating rates. Comparison among three groups of live individuals with different degrees of melanism did not clarify the influence of melanism on heating rates.However, when euthanized animals from the same three groups were compared, we observed that darker euthanized animals actually heat faster than lighter ones, favoring the TMH. Although unresolved aspects remain, body size and coloration influenced heat exchange, suggesting complex thermoregulatory strategies in these lizards, probably regulated through physiology and behavior, which may allow these small lizards to inhabit harsh weather environments. [ABSTRACT FROM AUTHOR]

Studies on reproductive modes, size at maturity, clutch size and clutch frequency have contributed greatly to our understanding of life history variation among lizard populations, and thereby, to implement conservation strategies. Herein, we studied the reproductive biology of the vulnerable tegu lizard Kentropyx viridistriga from Corrientes, northeastern Argentina (Wet Chaco). Kentropyx viridistriga are active from early summer to late autumn, with temperature and photoperiod influencing the timing of reproduction and the brumation period. Females showed an annual reproductive cycle, and males exhibited a continuous reproductive cycle during the activity season. Females laid at least two clutches of on average three eggs per reproductive season. Neonates occured in spring, and reached sexual maturity in the first year of life. Females reached sexual maturity at a larger snout-vent length (64.1 mm) than males (54.8 mm). Sexual dimorphism is evident, with males showing greater head size and longer tails than females, while females exhibit larger interlimb length than males. This study reveals that the reproductive strategy of K. viridistriga is adjusted to the environmental conditions of the southernmost distribution for the genus. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Zoology is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Several methods were developed with the aim of prioritizing conservation efforts. However, most of these methods were focused on ranking areas for land protection, without offering alternatives for sites poorly ranked. We propose an alternative method that allows prioritizing conservation efforts independently of the status of a specific area. The conservation priorities method considers data related with biodiversity, availability of suitable habitat and human pressure, on area-based units. This information is then standardized, obtaining a vector of three values, which reflects the situation of a specific area categorically (positive and negative) and quantitatively (how far from zero). Based on these values, specific conservation efforts can be settled at each area-based unit. We tested this methodology on several political units located at the Pampean Coastal Dunes in Argentina, using herpetofauna as surrogate taxon. Our results confirm the needs of performing several conservation approaches to deal with Pampean Coastal Dunes' problems. The conservation priorities method showed to be a useful tool to characterize sites and to set conservation efforts based on its specific status, supplementing current methodologies. [ABSTRACT FROM AUTHOR]

Home ranges of lizards are the result of both internal (body condition, reproductive status) and external factors, such as habitat features and resource availability. Habitat modification induced by introduced plants affects habitat use for lizards by changing food abundance, environmental temperatures or by homogenising the habitat structure. We compared the home range of the lizard Liolaemus wiegmannii in two situations: a partially forested habitat (20% of the total surface covered by Acacia longifolia) and a non-forested habitat. Twelve adult lizards were radio-tracked in the forested habitat and ten in the non-forested site. Home ranges were calculated using the minimum convex polygon method. The mean home range size was 37.80±17.95 m² and was not different between both habitat types. Home ranges of males were 1.6 times larger than those of females. Abundance of food was highest in the forested habitat, without an apparent effect on home range size. Home range in L. wiegmannii showed a marked association with mixed patches of native grassland, bare sand substrates and scarce coverage of exotic trees. Our data suggest that movements in L. wiegmannii may be mainly related to structural features (and their associated thermal cues) of specific microhabitat types. Although low levels of forestation with A. longifolia have less effect on the home range size and movements of lizards, we cannot ignore previous results showing that occurrence, abundance and body condition of L. wiegmannii are negatively affected by extensive forestation of exotic plants both at local and landscape scales in pampasic dunes. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Zoology is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Mexicana de Biodiversidad is the property of Universidad Nacional Autonoma de Mexico, Instituto de Biologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

For ectotherms like lizards, temperature plays a key role in shaping life history traits such as age and size at sexual maturity, longevity and growth. In cold, temperate habitats like Patagonia, balancing the energy expended to growth and reproduction is vital for persistence. In the present study, age and growth of the lizard Phymaturus spectabilis were studied using skeletochronology. We estimated individual ages, growth rates and life history parameters related to growth and reproduction. Juveniles were up to five years old. The youngest adult male was six years and the youngest adult female was seven years of age; females reached a higher longevity, and the oldest specimen was a female of 12 years. Resulting from the short activity season of Patagonia, P. spectabilis were characterised by delayed sexual maturity and medium longevity. Considering the rather short reproductive lifetime and small clutch size, P. spectabilis is characterised by the lowest net reproductive rate documented for liolaemids so far. This suggests that the capability to demographically recover from disturbances is low. [ABSTRACT FROM AUTHOR]

The introduction of nonnative plant species might generate habitat modifications that, in turn, increase the predation risk for animals, either by making prey species more conspicuous, limiting the availability of refuges, or by offering vantage points to potential predators. We compared predation pressure and escape behavior of two sympatric species ( Liolaemus wiegmannii and Liolaemus multimaculatus) of Sand Lizards inhabiting forested and nonforested grasslands of the pampasic coastal sand dunes of Argentina. Predation pressure was evaluated by measuring the predation rate on plasticine replicas of lizards and the abundance of avian predators. We also recorded flight initiation distance (FID) of lizards in the different habitat types and the microhabitat used as refuge. Both lizard species prefer refuges in native plants but, when they are scarce, the nonnative Acacia longifolia is selected as alternative refuge. In forested habitats, sand-burying behavior is a complementary strategy used by L. multimaculatus to avoid predation. The FID of L. wiegmannii was greater in forested habitats than in nonforested ones. In contrast, L. multimaculatus exhibited a short FID in forested habitats, mostly because sand-burying behavior appears to reduce the risks typically associated with exposed areas. Plasticity in antipredatory behavior suggests that these lizards could recognize predators and develop a suitable antipredatory behavior. We conclude that increased predation pressure and structural alterations of the habitat in the presence of nonnative A. longifolia affect the decisions that determine how, when, and where these lizards flee. [ABSTRACT FROM AUTHOR]

We provide a well-supported phylogenetic hypothesis for all recognized lineages of the Liolaemus kriegi complex based on a multilocus dataset. We used 29 individuals from the eight taxa included in this complex for which we sequenced eight gene regions (two mitochondrial and six nuclear). We implemented maximum likelihood and Bayesian inference methods for the mitochondrial, nuclear, and concatenated sequences and employed BEAST to estimate the species tree. The all genes concatenated analyses and the species trees recovered the L. kriegi complex as monophyletic with high support, including three described species ( L. kriegi, Liolaemus ceii, and Liolaemus buergeri) and three previously identified candidate species ( Liolaemus sp. A, Liolaemus sp. C, and Liolaemus sp. D), with Liolaemus tregenzai as a closely related taxon. Another previously proposed candidate species ( L. sp. B) has a labile topological position that varies depending on the type of markers and analytical methods used. In the mitochondrial gene tree, L. sp. B is recovered within the L. kriegi complex whereas in the 'all genes concatenated' analyses and in the nuclear species tree analyses, it is recovered outside of this complex as sister to Liolaemus petrophilus (a representative of the L. petrophilus group). Morphologically, L. sp. B is indistinguishable from L. austromendocinus (also included in the L. petrophilus group); thus, we do not consider L. sp. B as part of the L. kriegi complex. We estimated divergence times for the major clades of the complex based on the species tree hypothesis, and all were inferred to have a Pleistocene origin. [ABSTRACT FROM AUTHOR]

Neriidae are a small family of acalyptratae flies, mostly distributed in the tropics. Very little is known about their biology, and the evolutionary relationships among species have never been evaluated. We perform the first comprehensive phylogenetic analysis of the family, including 48 species from all biogeographic regions inhabited, as well as five species of Micropezidae and one Cypselosomatidae as outgroups. We build a morphological data matrix of 194 characters, including 72 continuous characters. We first explore ways to deal with the issue of scaling continuous characters, including rescaling ranges to unity and using implied weighting. We find that both strategies result in very different phylogenetic hypotheses, and that implied weighting reduces the problem of scaling, but only partially. Furthermore, using implied weighting after rescaling characters improves the congruence between partitions and results in higher values of group support. With respect to the Neriidae, we confirm the monophyly of the family and of most its genera, although we do not obtain any of the currently accepted suprageneric groups. We propose to restrict the Eoneria and Nerius groups exclusively to the Neotropical fauna, and synonymize Glyphidops subgenus Oncopsia Enderlein with Glyphidops subgenus Glyphidops Enderlein, eliminating the subgeneric divisions. This revised phylogeny presents a striking biogeographic consistency, and shows that previous main divisions of the family were based on events of convergence. [ABSTRACT FROM AUTHOR]