It is predicted that climate change will cause species extinctions and distributional shifts in coming decades, but data to validate these predictions are relatively scarce. Here, we compare recent and historical surveys for 48 Mexican lizard species at 200 sites. Since 1975, 12% of local populations have gone extinct. We verified physiological models of extinction risk with observed local extinctions and extended projections worldwide. Since 1975, we estimate that 4% of local populations have gone extinct worldwide, but by 2080 local extinctions are projected to reach 39% worldwide, and species extinctions may reach 20%. Global extinction projections were validated with local extinctions observed from 1975 to 2009 for regional biotas on four other continents, suggesting that lizards have already crossed a threshold for extinctions caused by climate change.

Anolis lizards are one of the most diverse vertebrate genera and are the classic example of adaptive radiation and convergent evolution. Anoles exhibit great morphological diversity produced by the ecological opportunity to exploit several arboreal niches. Anole radiation in the Caribbean islands is well studied, but the mainland radiation is less understood. We used a large morphological data set and a molecular phylogeny to describe the morphological diversification of anoles from northwestern South America, a region with the highest anole diversity on a mainland. We describe morphological diversity as summarized by ten morphotypes, defined mainly by body size, limb proportions, and subdigital lamellae. We show that some morphotypes are limited to forested lowlands and others to Andean highlands; by contrast, Anolis assemblages from tropical rainforests are comprised of the same four morphotypes. We demonstrate that morphological diversification followed a pattern of adaptive radiation across a landscape of adaptive peaks. Our results are consistent with the most recent hypothesis of convergence stated for Caribbean radiation, and demonstrate convergence between mainland morphotypes and Caribbean ecomorphs, which suggests that common processes are driving both radiations. © 2016 The Linnean Society of London

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Colombia is a megadiverse country with about 600 species of reptiles; however, there are few studies on species of hemoparasites found in this taxonomic group. Here, we document the presence of Plasmodium spp. in four species of reptiles from the northern part of the Orinoco-Amazon region in Colombia. Individuals analyzed in this study were captured in localities between 200 and 500 m altitude, in the department of Guaviare. Each sample was screened for haemosporidian parasites by using morphology and a nested polymerase chain reaction (PCR) protocol that targets the mitochondrial cytochrome b (cytb) gene. Four morphotypes of the genus Plasmodium were found; two of these species are re-described using morphological and molecular data (cytb). For the other two morphotypes, it was not possible to assign a described species. Among those, Plasmodium screened one species was only detected by microscopy. Considering the potential species diversity, it is possible that commonly used primers may not detect all species, reinforcing the importance of using microscopy in haematozoa surveys. There was no correspondence between the morphological traits associated with the subgenera and the phylogenetic relationships that we found in our analyses. Additionally, we found an expansion in the geographical distribution of these two species, and a new host for P. kentropyxi, demonstrating that studies of tropical herpetofauna and their parasites deserve more attention.

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ABSTRACT. Low thermal quality environments, such extreme latitudes or high elevation regions, are highly expensive for reptiles in terms of thermoregulation. Thus, physiological adaptations or behavioral adjustments to live in these habitats have evolved in some species. Anolis heterodermus (Duméril, 1851) is an anole lizard that lives at high elevations in the Andes region. In this paper, we attempted to elucidate the thermoregulation strategy of a population of this species from the eastern cordillera of Colombia during wet and dry seasons. We measured body temperatures (T b ), operative temperatures (T e ) and preferred temperatures (T pref ). Based on these data, we obtained accuracy (d̄b), environmental thermal quality (d̄e) and effi ciency of thermoregulation (E) indexes. There were no signifi cant diff erences of T b or d̄b between seasons, sexes, ages, and for T pref between sexes or ages, but we found diff erences in T e and d̄e between seasons. The indexes suggested high thermoregulatory accuracy, low thermal environment quality and indicated that A. heterodermus was an active thermoregulator in both seasons. Broad ranges of T b and the species association with microhabitats with high solar radiation suggest eurythermy and heliothermy. Anolis heterodermus lives in a low thermal quality habitat, using exposed perches, which seems the most effi cient thermal microhabitats. We concluded that A. heterodermus performed behavioral adjustment for compensating seasonal variation in the environmental thermal costs.KEYWORDS. Thermal quality, thermoregulatory accuracy, seasonal variation, heliothermy.RESUMEN. Termorregulación en el lagarto andino Anolis heterodermus (Squamata: Dactyloidae) a una alta elevación en la Cordillera Oriental de Colombia. Ambientes con baja calidad térmica, tales como las latitudes extremas o regiones en altas elevaciones, son altamente costosos para los reptiles en términos de termorregulación, por lo cual algunas especies han adquirido adaptaciones fi siológicas o ajustes conductuales para habitar estos ambientes. Anolis heterodermus (Duméril, 1851) es un lagarto que habita a altas elevaciones en la región andina. En el presente trabajo se evaluó la termorregulación de una población de esta especie en la cordillera oriental de Colombia durante las épocas húmeda y seca. Se midieron temperaturas corporales (T b ), operativas (T e ) y de preferencia (T pref ). Con base en estas variables, se obtuvieron los índices de calidad térmica ambiental (d̄e), exactitud (d̄b) y efi ciencia (E) de la termorregulación. No hubo diferencias signifi cativas entre la T b o d̄b entre épocas, sexos o edades y tampoco de la T pref entre sexos o edades, pero encontramos diferencias de T e y d̄e entre épocas. Los índices sugieren alta exactitud termorreguladora y baja calidad térmica del ambiente, por lo tanto indican que A. heterodermus es un termorregulador activo para ambas épocas. El amplio intervalo de T b y la asociación de la especie a microhábitats con alta radiación solar sugieren euritérmia y heliot...

The coexistence of several anoles in the same place is attributed to differential partitioning of resources. Although several mainland and island communities show a similar structure, differences in life-history traits, absence of niche complementarity, higher food supply and higher numbers of predators in mainland environments support the idea that predation, rather than competition, is a more important structuring force in mainland than in island anole communities. To analyse the pattern of ecological structure in mainland anole communities, we studied communities in three tropical rain forests of north-western South America to obtain data about the use of resources on three niche axes [spatial, thermal and morphological (as a proxy of diet)] for 17 species of anoles. We analysed the patterns of niche overlap for each axis and found that overlap on the dietary axis was less than the overlap on the other axes, indicating that species using similar spatial or thermal resources diverge strongly in their diet. In addition, we identified a niche complementarity among niche axes, suggesting that intraspecific competition is also an important process in those communities. Finally, this study revealed a similar ecological structure in different communities of mainland rain-forest anoles, which share seven ecomorphs, suggesting ecological adaptation and convergence in mainland anoles.