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Altered environments in urban areas are known to impact and change animal behaviour. In particular, artificial light at night (ALAN) affects behaviour across taxonomic groups, including reptiles. Geckos in the genus Phelsuma are predominantly diurnal, but some have been documented to alter their foraging behaviour from a diurnal to nocturnal activity period when they have access to artificial light sources. Herein, we report new observations of six Phelsuma spp. (Andaman day geckos, P. andamanensis; blue‐tailed day geckos, P. cepediana; Madagascar giant day geckos, P. grandis; Reunion ornate day geckos, P. inexpectata; gold dust day geckos, P. laticauda; Mahe day geckos, P. sundbergi longinsulae) using artificial lights to engage in nocturnal activity that includes foraging, courtship, and agonistic behaviour. Artificial light at night augments the amount of time predators, especially visual predators, can spend foraging. This can increase their overall daily activity period (i.e. the amount of time spent active within 24 h), and research is yet to fully understand the cost–benefit trade‐offs this altered behaviour has on individual fitness. Overall, our novel accounts of six Phelsuma spp. contribute to knowledge regarding the diversity of animals that have altered their behaviour in response to ALAN and highlight the behavioural flexibility of this group of geckos.

Temperature-induced developmental plasticity could allow amphibian larvae to complete metamorphosis successfully despite new thermal challenges and increased desiccation risk due to climate change. Here we investigated how the capacity for temperature-induced developmental plasticity varies with latitude and whether population-specific biogeographic background accounts for the different degree of plastic responses to temperature. We carried out a combined analysis based on the data from 150 studies (93 articles) performed on 64 amphibian species. We collected empirical data for age and size at metamorphosis in amphibian larvae acclimated to different temperatures during development and found that all larvae from all populations in these studies revealed a change in metamorphic traits with a given change in temperature and thus, were able to exhibit temperature-induced developmental plasticity. Age at metamorphosis was more affected by temperature than size at metamorphosis. Age and size at the onset of metamorphosis were generally lowest at warmest temperatures during development. Furthermore, populations from tropical latitudes were less sensitive to a change in developmental temperature compared to populations from higher latitudes. Accordingly, we suggest tropical populations to be the most vulnerable to increasing temperatures during metamorphosis. Our analyses reveal biases with respect to taxonomy, biogeographic distribution of species, and study design. Data from tropical populations are underrepresented and thus, the capacity for developmental plasticity of the most threatened species probably remains poorly understood. Future studies should focus on under-represented regions, most threatened species, and include a broader range of temperatures during development in order to make robust projections on future sensitivity of populations to climate change.

The Indian egg-eater (Elachistodon westermanni) is a monotypic species of the Genus Elachistodon distributed across the Indian sub-continent. In Africa, there are 13 species of egg-eating snakes of the Genus Dasypeltis. These two genera, Elachistodon and Dasypeltis were thought to be closely related due to similar diet specialization, and shared biogeographic history between the Indian sub-continent and the continent of Africa. In our study, we amplified three mitochondrial genes and one nuclear gene from E. westermanni and reconstructed molecular phylogeny utilizing published sequences to understand the evolutionary relationships between the African, and the Indian egg-eating snakes. We used morphological characters to reinforce our inferences on phylogenetic relationships. We show that the Indian egg-eater is sister to cat snakes of the Genus Boiga, and it does not share recent ancestry with the African egg-eating snakes. Morphological character states point at similarities between Elachistodon and Dasypeltis only in characters associated with their feeding behaviour. Elachistodon westermanni was similar to the Boiga spp. in several other morphological characters, and we provisionally assign E. westermanni under the genus Boiga. Compilation of records of E. westermanni across the Indian sub-continent over the years revealed a positive “Lazarus” effect. We conclude that, the egg-eating behaviour and the associated morphological characters in the snake genera Dasypeltis and Elachistodon are a result of convergent evolution. Based on the conservation status of E. westermanni, it could serve as a flagship species to conserve important wildlife habitats that are being lost rapidly in India.

Made available in DSpace on 2022-04-28T19:44:50Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-12-01 The 71 currently known species of dwarf geckos of the genus Lygodactylus are a clade of biogeographic interest due to their occurrence in continental Africa, Madagascar, and South America. Furthermore, because many species are morphologically cryptic, our knowledge of species-level diversity within this genus is incomplete, as indicated by numerous unnamed genetic lineages revealed in previous molecular studies. Here we provide an extensive multigene phylogeny covering 56 of the named Lygodactylus species, four named subspecies, and 34 candidate species of which 19 are newly identified in this study. Phylogenetic analyses, based on ∼10.1 kbp concatenated sequences of eight nuclear-encoded and five mitochondrial gene fragments, confirm the monophyly of 14 Lygodactylus species groups, arranged in four major clades. We recover two clades splitting from basal nodes, one comprising exclusively Malagasy species groups, and the other containing three clades. In the latter, there is a clade with only Madagascar species, which is followed by a clade containing three African and one South American species groups, and its sister clade containing six African and two Malagasy species groups. Relationships among species groups within these latter clades remain weakly supported. We reconstruct a Lygodactylus timetree based on a novel fossil-dated phylotranscriptomic tree of squamates, in which we included data from two newly sequenced Lygodactylus transcriptomes. We estimate the crown diversification of Lygodactylus started at 46 mya, and the dispersal of Lygodactylus among the main landmasses in the Oligocene and Miocene, 35–22 mya, but emphasize the wide confidence intervals of these estimates. The phylogeny suggests an initial out-of-Madagascar dispersal as most parsimonious, but accounting for poorly resolved nodes, an out-of-Africa scenario may only require one extra dispersal step. More accurate inferences into the biogeographic history of these geckos will likely require broader sampling of related genera and phylogenomic approaches to provide better topological support. A survey of morphological characters revealed that most of the major clades and species groups within Lygodactylus cannot be unambiguously characterized by external morphology alone, neither by unique character states nor by a diagnostic combination of character states. Thus, any future taxonomic work will likely benefit from integrative, phylogenomic approaches. Zoological Institute Technical University of Braunschweig, Mendelssohnstr. 4 State Natural History Museum of Braunschweig, Pockelsstr. 10 Department of Biological Sciences Rutgers University-Newark, 195 University Avenue Faculty of Mathematics and Natural Sciences Institute for Biochemistry and Biology University of Potsdam Department of Biology University of Florida, 220 Bartram Hall Departamento de Biodiversidade Instituto de Biociências Universidade Estadual Paulista (UNESP), Campus Rio Claro, Avenida 24A, N 1515 Bela Vista Santa Fe College, 3000 NW 83rd St. Florida Museum of Natural History Division of Herpetology, 1659 Museum Road – Dickinson Hall Zoologische Staatssammlung München (ZSM-SNSB), Münchhausenstraße 21 Department of Biology and Center for Biodiversity and Ecosystem Stewardship Villanova University, 800 Lancaster Avenue Departamento de Biodiversidade Instituto de Biociências Universidade Estadual Paulista (UNESP), Campus Rio Claro, Avenida 24A, N 1515 Bela Vista

We describe a new species of rock-dwelling gecko, Hemidactylus paaragowlipaaragowli sp. nov., from the Agastyamalai Hill Range, in the southern Western Ghats. Morphological and molecular data support the distinctiveness of the species and its close relationship to other large-bodied, tuberculate Hemidactylus spp. from the H. prashadi group from India and Sri Lanka. This species belongs to a rupicolous complex and can be distinguished from other members of the group based on the following characters: 22–24 longitudinal rows of fairly regularly arranged, subtrihedral, weakly keeled, striated tubercles at midbody; 9–11 and 10–12 subdigital lamellae on the first and fourth digits, respectively, of both manus and pes; tail with transverse series of four enlarged tubercles on each tail segment; 10–12 femoral pores on each side separated by 16–18 scales without pores; 11–13 supralabials and 9–10 infralabials.

Limited gene flow between populations due to geographic distance, presence of barriers or inherent low dispersal ability leads to the formation of genetically structured populations. Strong population structure indicates lowered levels or absence of gene flow which might lead to inbreeding and loss of genetic capacity to recuperate from anthropogenic stress and natural calamities. Terrestrial reptiles are generally known to have low dispersal abilities and few studies have explored drivers of their population structure on continental islands, where both anthropogenic stress and natural calamities are relatively common. We investigated the population structure and drivers of diversification of the Andaman keelback (Xenochrophis tytleri), an endemic, terrestrial and freshwater snake species in the Andaman archipelago, a continental group of islands in the Bay of Bengal. Data was collected from 86 individuals from seven islands and 78 individuals were sequenced for the gene Nuclear Dehydrogenase subunit 4 to identify the number of populations and distribution of genetic diversity across populations. We found 11 haplotypes on seven islands and observed high genetic differentiation between seven populations defined island-wise (FST= 0.82). We further tested the number of populations by incorporating spatial data into Bayesian Clustering Analysis (GENELAND) and identified six populations of the Andaman keelback. We tested for the influence of Isolation-by-distance on these populations. While the overall trend showed a positive correlation between geographic and genetic distance, a correlogram revealed that the positive correlation disappears beyond ∼20–40 km. We also tested for the presence of geographical barriers to gene flow using Monmonier’s algorithm (SPADS), which identified five barriers to dispersal confirming that there are oceanic barriers to dispersal for some island populations of the Andaman keelback. As the Andaman Islands are arranged almost in a straight line from North to South, our data are insufficient to tease apart the roles of geographical distance and barriers to gene flow. We conclude that salt waters between near islands are weak barriers and as the geographical distance between islands increases, so does the strength of the barrier.