Leaf-toed Gecko Research Articles

Hidden in the bark: the unexpected presence of the leaf-toed gecko, Euleptes europaea (Gené, 1839) (Squamata, Sphaerodactylidae), in Sicily

Hidden in the bark: the unexpected presence of the leaf-toed gecko, Euleptes europaea (Gené, 1839) (Squamata, Sphaerodactylidae), in Sicily

Clinging on the brink: Whole genomes reveal human-induced population declines and severe inbreeding in the Critically Endangered Emirati Leaf-toed Gecko (Asaccus caudivolvulus).

Human-mediated habitat destruction has had a profound impact on increased species extinction rates and population declines worldwide. The coastal development in the United Arab Emirates (UAE) over the last two decades, serves as an example of how habitat transformation can alter the landscape of a country in just a few years. Here, we study the genomic implications of habitat transformation in the Critically Endangered Emirati Leaf-toed Gecko (Asaccus caudivolvulus), the only endemic vertebrate of the UAE. We generate a high-quality reference genome for this gecko, representing the first reference genome for the family Phyllodactylidae, and produce whole-genome resequencing data for 23 specimens from 10 different species of leaf-toed geckos. Our results show that A. caudivolvulus has consistently lower genetic diversity than any other Arabian species of Asaccus, suggesting a history of ancient population declines. However, high levels of recent inbreeding are recorded among populations in heavily developed areas, with a more than 50% increase in long runs of homozygosity within a 9-year period. Moreover, results suggest that this species does not effectively purge deleterious mutations, hence making it more vulnerable to future stochastic threats. Overall, results show that A. caudivolvulus is in urgent need of protection, and habitat preservation must be warranted to ensure the species' survival.

Integrating phylogenetic, phylogeographic, and morphometric analyses to reveal cryptic lineages within the genus Asaccus (Reptilia: Squamata: Phyllodactylidae) in Iran

The Middle Eastern endemic genus Asaccus comprises Southwest Asian leaf-toed geckos. To date, this genus includes 19 species of leaf-toed geckos (seven in Arabia and 12 in the Zagros Mountains). Despite a recent study on the taxonomy and phylogeny of Asaccus species in Iran, controversies still remain surrounding the phylogeny and phylogeography of the genus. Here, we used an integrative approach to determine the phylogeny and phylogeography of Asaccus species using two mitochondrial genes (12 S and Cyt b), and one nuclear gene (c-mos). Our results uncovered 22 distinct lineages, demonstrating a significant cryptic diversity that challenges the current morphological classifications of these species. Phylogenetic analyses reinforce the monophyly of the Asaccus group, positioning A. montanus as a basal lineage, which supports a deep evolutionary divergence dating back to the Late Oligocene, approximately 27.94 million years ago. This genetic diversity also highlights the impact of historical climatic and geographical changes on species diversification. The findings advocate for an integrative approach combining both molecular and morphological data to resolve species identities accurately, thereby enhancing conservation strategies to protect these genetically distinct lineages.

Insights into the Gut Microbiome of the South American Leaf-Toed Gecko (Phylodactylus gerropygus) Inhabiting the Core of the Atacama Desert.

Living in arid environments presents unique challenges to organisms, including limited food and water, extreme temperatures, and UV exposure. Reptiles, such as the South American leaf-toed gecko (Phyllodactylus gerrhopygus), have evolved remarkable adaptations to thrive in such harsh conditions. The gut microbiome plays a critical role in host adaptation and health, yet its composition remains poorly characterized in desert reptiles. This study aimed to characterize the composition and abundance of the gut microbiome in P. gerrhopygus inhabiting the hyperarid Atacama Desert, taking into account potential sex differences. Fecal samples from adult female and male geckos were analyzed by 16S rRNA gene amplicon sequencing. No significant differences in bacterial alpha diversity were observed between the sexes. However, the phylum Bacteroidota was more abundant in females, while males had a higher Firmicutes/Bacteroidota ratio. The core microbiome was dominated by the phyla Bacteroidota, Firmicutes, and Proteobacteria in both sexes. Analysis of bacterial composition revealed 481 amplicon sequence variants (ASVs) shared by female and male geckos. In addition, 108 unique ASVs were exclusive to females, while 244 ASVs were unique to males. Although the overall bacterial composition did not differ significantly between the sexes, certain taxa exhibited higher relative abundances in each sex group. This study provides insight into the taxonomic structure of the gut microbiome in a desert-adapted reptile and highlights potential sex-specific differences. Understanding these microbial communities is critical for elucidating the mechanisms underlying host resilience in Earth's most arid environments, and for informing conservation efforts in the face of ongoing climate change.

Another new micro-endemic, limestone-dwelling leaf-toed gecko (Gekkonidae: Dixonius) from Phetchaburi Province, western Thailand

We describe Dixonius chotjuckdikuli sp. nov. from Khao Ebid (Mount Ibit), Khao Yoi District, Phetchaburi Province, western Thailand. The new, limestone-dwelling species differs from all currently recognized species of Dixonius by the following combination of morphological characters and pattern: maximal known snout-vent length of 45.6 mm, 18 (rarely 16) longitudinal rows of dorsal tubercles; 31 to 34 paravertebral scales; 18 (rarely 16) longitudinal rows of ventral scales across the abdomen; 20 to 22 interciliary scales; 5 or 6 precloacal pores in males, no pores in females; a marked canthal stripe extending beyond the shoulder; and a blotched dorsal pattern in males, females and juveniles. This description brings the number of Dixonius species to 17, among which seven species are endemic to Thailand.

One gecko’s pain is another gecko’s gain: is the Moorish gecko Tarentola mauritanica becoming invasive in France?

The Moorish gecko Tarentola mauritanica is currently expanding around the Mediterranean basin as a result of natural dispersal and anthropogenic spread. The species is observed at several sites in sympatry with other gecko species. To date, no impact has been observed on the native species and T. mauritanica is not considered invasive. We present an eight-year survey in southern France, where it lives in sympatry with the European leaf-toed gecko Euleptes europaea. The survey started when the Moorish gecko was rare which enabled us to observe an important increase in abundance. This increase was strongly correlated with a notable decline of E. europaea, explaining 49% of transect-specific temporal variation in abundance. We suspect that the increase in T. mauritanica density is causally related to this decline and recommend intensive monitoring of the species throughout the Mediterranean basin to determine whether or not the species should be classified as invasive. Keywords: Euleptes europaea, Tarentola mauritanica, temporal trends, biotic interaction, competition, invasive alien species

Population genomics reveals how 5 ka of human occupancy led the Lima leaf-toed gecko (Phyllodactylus sentosus) to the brink of extinction

Small species with high home fidelity, high ecological specialization or low vagility are particularly prone to suffer from habitat modification and fragmentation. The Lima leaf-toed gecko (Phyllodactylus sentosus) is a critically endangered Peruvian species that shelters mostly in pre-Incan archeological areas called huacas, where the original environmental conditions are maintained. We used genotyping by sequencing to understand the population genomic history of P. sentosus. We found low genetic diversity (He 0.0406–0.134 and nucleotide diversity 0.0812–0.145) and deviations of the observed heterozygosity relative to the expected heterozygosity in some populations (Fis − 0.0202 to 0.0187). In all analyses, a clear population structuring was observed that cannot be explained by isolation by distance alone. Also, low levels of historical gene flow were observed between most populations, which decreased as shown in contemporary migration rate analysis. Demographic inference suggests these populations experienced bottleneck events during the last 5 ka. These results indicate that habitat modification since pre-Incan civilizations severely affected these populations, which currently face even more drastic urbanization threats. Finally, our predictions show that this species could become extinct in a decade without further intervention, which calls for urgent conservation actions being undertaken.

The secret life of a rock-dweller: arboreal acrobatics observed in the European leaf-toed gecko Euleptes europaea

The European leaf toed Gecko,Euleptes europaea, is a strictly nocturnal species endemic to the western Mediterranean and has long been considered a rock-specialist as it is associated with this habitat during its entire daily and life cycle. In this study, we report observations of arboreal behaviour inE. europaea, collected during field research over a 40-year period from across the entire species range. We provide a review of the available information on this topic that contributes to a refined view of the habitat uses and arboreal abilities of this species. Arboreal behaviour inE. europaeawas observed throughout the year, across different macrohabitats, on a wide variety of tree, shrub, and bush species, on various parts of the plant (trunk, branches, fronds, twigs, leaves), and at different height from the ground. Remarkably,E. europaeashows an extraordinarily agile arboreal locomotion associated with striking morphological adaptations to an arboreal lifestyle, namely a prehensile tail bearing a terminal adhesive pad that supplements grasping force, an equilibrium asset, and scansor adhesion both in static condition and during escape. We conclude thatE. europaeais a climbing gecko (opposed to ground dwelling), occupying both rocky and arboreal microhabitats. While the evolutionary origin and ecological drivers of the arboreal behaviour ofE. europaearemains to be fully investigated, this realization has important implications for designing fieldwork research and management strategies for conservation.

A new species of feather-tailed leaf-toed gecko, Kolekanos Heinicke, Daza, Greenbaum, Jackman, Bauer, 2014 (Squamata, Gekkonidae) from the poorly explored savannah of western Angola.

We here describe a new species of feather-tailed leaf-toed gecko, Kolekanos, from southern Benguela Province, Angola, based on morphological and osteological evidence, supported by phylogenetic analysis of mitochondrial data. The new species adds to the rapidly growing and newly-recognised endemic biodiversity of Angola, doubling the number of Kolekanos species, breaking the pattern observed within other closely-related African members of a clade of circum-Indian Ocean leaf-toed geckos - Ramigekko, Cryptactites and Afrogecko - all of which are presently monotypic. The new species is easily distinguished from K.plumicaudus, based on spine-like (as opposed to feather-like) scales on the margins of the original tail. Phylogenetic analyses also recovered the new taxon as monophyletic, with a well-supported sister relationship to K.plumicaudus, from which it differs by a substantial 24.1% NADH-dehydrogenase subunit 2 mitochondrial gene uncorrected p-distance.

Forest cover and geographical distance influence fine-scale genetic structure of leaf-toed geckos in the tropical dry forests of western Mexico

Abstract The biodiversity within tropical dry forests (TDFs) is astounding and yet poorly catalogued due to inadequate sampling and the presence of cryptic species. In the Mexican TDF, endemic species are common, and the landscape has been continually altered by geological and anthropogenic changes. To understand how landscape and environmental variables have shaped the population structure of endemic species, we studied the recently described species of leaf-toed gecko, Phyllodactylus benedettii, in coastal western Mexico. Using double-digest restriction site-associated DNA sequencing data, we first explore population structure and estimate the number of ancestral populations. The results indicate a high degree of genetic structure with little admixture, and patterns corresponding to both latitudinal and altitudinal gradients. We find that genetic structure cannot be explained purely by geographical distance, and that ecological corridors may facilitate dispersal and gene flow. We then model the spatial distribution of P. benedettii in the TDF through time and find that the coastline has been climatically suitable for the species since the Last Glacial Maximum. Landscape genetic analyses suggest that the combination of isolation by distance (IBD) and isolation by resistance (IBR; forest cover) has influenced the spatial genetic structure of the species. Overall, our genomic data demonstrate fine-scale population structure in TDF habitat, a complex colonization history, and spatial patterns consistent with both IBD and other ecological factors. These results further highlight the Mexican TDF as a diversity hotspot and suggest that continued anthropogenic changes are likely to affect native fauna.

Systematic revision of Afrogecko ansorgii (Boulenger, 1907) (Sauria: Gekkonidae) from western Angola

Here we provide the first phylogenetic analysis that include Afrogecko ansorgii and a detailed morphological comparison with other species of leaf-toed geckos. For this purpose, we used two mitochondrial (16S, ND2) and four nuclear (RAG1, RAG2, CMOS, PDC) genes to produce a robust phylogenetic reconstruction. This allowed us to show that A. ansorgii is not related as previously believed to circum-Indian Ocean leaf-toed geckos and is rather more closely related to other Malagasy leaf-toed geckos. Additionally, we explore and compare osteological variation in A. ansorgii skulls through High Resolution X-ray Computed Tomography with previously published material. This allowed us to describe herein a new genus, Bauerius gen. nov., and additionally provide a detailed redescription of the species (including the first description of male material), supplementing the limited original description and type series, which consisted of only two females.

Redescription of Hemidactylus giganteus Stoliczka, 1871 with the description of three new allied species (Squamata: Gekkonidae: Hemidactylus Goldfuss, 1820) from peninsular India.

We revise the systematics of Hemidactylus giganteusan Indian endemic leaf-toed gecko based on recent collections from the type locality and other localities in peninsular India. We provide a comprehensive redescription of H. giganteus sensu stricto and describe three new allied species from the Karnataka and Telangana states in India. We analysed the phylogenetic relationships between the three new species, H. raya sp. nov., H. saxicolus sp. nov., and H. aemulus sp. nov., and found them to be nested within the H. giganteus sensu lato branch. The pairwise genetic divergence between these new cryptic taxa from H. giganteus sensu stricto ranged from 5.88% to 10.95% for the Cyt b gene. The new species also differ from H. giganteus sensu stricto based on number of femoral pores on each thigh and poreless scales separating them (1823 femoral pores and seven or eight poreless scales versus 17 femoral pores and seven poreless scales in H. raya sp. nov., 26 or 27 femoral pores and nine poreless scales in H. saxicolus sp. nov., and 2225 femoral pores and nine to ten poreless scales in H. aemulus sp. nov.), corroborated by linear discriminant analysis based on 29 morphometric and meristic characters. Our species delimitation analysis shows the presence of three additional putative new species awaiting formal description within the H. giganteus sensu lato branch.

Comparative Phylogeography of Floreana's Lizards Supports Galápagos Pleistocene Paleogeographical Model and Informs Conservation Management Decisions

Terrestrial squamate reptiles from the Galápagos archipelago have limited gene flow among islands, which provides an opportunity to test paleogeographic models. Previous work suggests that Pleistocene glaciations had a strong influence on the evolution of Galápagos's sea-locked vertebrates by allowing dispersal and contact among populations from different islands through land connections for the last 700,000 yr. A prediction of the model is that extant populations, despite being isolated at present, are more genetically similar than would be expected given their age of origin due to recent (Pleistocene) gene flow. Based on mitochondrial genes, we test the prediction with a comparative phylogeographic analysis of two sympatric species of lizards (Microlophus grayii and Phyllodactylus baurii) from Floreana island and two surrounding islets. As expected by the paleogeographic model, lizards from Floreana are very similar genetically to conspecifics from Champion, which, unlike Gardner, was connected to Floreana during Pleistocene glacial maxima. Moreover, populations of Floreana and Champion do not share haplotypes, suggesting that genetic drift played an important role in their evolution. The split between Gardner and Floreana plus Champion populations was estimated at 0.99 million years ago (mya) for Lava Lizards and 3.41 mya for Leaf-toed Geckos, whereas the split between populations from Floreana and Champion was 0.72 and 2.43 mya, respectively. Our results also show that Floreana and Champion populations are part of the same evolutionarily significant unit for each species, which might be at risk due to an upcoming invasive mammal eradication program in Floreana. Therefore, Champion represents a reasonable source for potential reintroductions if necessary.

A new species of leaf-toed gecko (Phyllodactylidae, Phyllodactylus) from María Cleofas Island, Nayarit, Mexico.

We describe a new species of leaf-toed gecko of the genus Phyllodactylus from María Cleofas Island, the smallest island of Tres Marías Archipelago, Nayarit, México. Genomic, phylogenomic, and morphological evidence support that the new species presents a unique combination of diagnostic characters. Morphologically, the new species has a high number of tubercles, head to tail (mean 47), longitudinal ventral scales (mean 61), and third labial–snout scales (mean 26). Gene flow tests revealed the genetic isolation of insular populations from mainland counterparts. In addition, we confirmed the non-monophyly of P. homolepidurus and P. nolascoensis, and we show that the taxon P. t. saxatilis is a complex; therefore, we propose taxonomic changes within the saxatilis clade. The discovery of this new insular endemic species highlights the urgency of continued exploration of the biological diversity of island faunas of Mexico.

A new leaf-toed gecko (Gekkonidae: Dixonius) from the city of Ranong, southwestern Thailand.

We describe Dixonius dulayaphitakorum sp. nov. from Ranong city, Ranong Province, southern peninsular Thailand. The new, ground-dwelling species differs from all currently recognized Dixonius by a combination of morphological characters and pattern: maximal known SVL of 47.8 mm, 22 longitudinal rows of dorsal tubercles; 33 to 35 paravertebral scales; 22 longitudinal rows of ventrals across the abdomen; six or seven precloacal pores in males, no pores in females; no distinct canthal stripe; and a spotted dorsal pattern. Based on dorsal pattern, the new species seems related to Dixonius siamensis. This description brings to 11 the number of Dixonius species, and to five the ones endemic to Thailand.

A new limestone-dwelling leaf-toed gecko (Gekkonidae: Dixonius) from coastal hills in Cha-am, peninsular Thailand.

We describe Dixonius pawangkhananti sp. nov. from coastal limestone hills in Cha-am District, Phetchaburi Province, peninsular Thailand. The new species differs from all currently recognized Dixonius by the following combination of morphological characters and pattern: maximal known snout-vent length of 42.6 mm; 16 longitudinal rows of dorsal tubercles; 30 to 32 paravertebral scales; 16 longitudinal rows of ventral scales across the abdomen; six precloacal pores in males, no pores in females; a marked canthal stripe; and a sexually dimorphic dorsal pattern consisting of bands (males) or blotches (females). This description brings the number of Dixonius species to ten, with four species endemic to Thailand.

Tiny but “strong”: the European Leaf-toed gecko, Euleptes europaea, a terrestrial vertebrate able to survive on tiny islets

The present paper focuses on the ability of the European Leaf-toed gecko, Euleptes europaea, an endemic species of the western Mediterranean, to live in low-nutrient habitats. Its distribution is mainly insular and particularly noteworthy is its ability to live on islets and rocks. This work includes data originating from surveys carried out on 111 islands surrounding the island of Corsica (France) in search of herpetofauna. E. europaea is able to survive on the smallest islets, with low habitat complexity, suggesting a pre-adaptation of this species to island life. Moreover, high population densities associated with a low biomass seem to facilitate survival on island.

Phylogenomics and molecular species delimitation reveals great cryptic diversity of leaf-toed geckos (Phyllodactylidae: Phyllodactylus), ancient origins, and diversification in Mexico

We utilize the efficient GBS technique to obtain thousands of nuclear loci and SNPs to reconstruct the evolutionary history of Mexican leaf-toed geckos (Phyllodactylus). Through the incorporation of unprecedented sampling for this group of geckos, in combination with genomic data analysis, we generate mostly consistent phylogenetic hypotheses using two approaches: supermatrix and coalescent-based inference. All topologies depict three, mutually exclusive major clades. Clade I comprises P. bordai and all species closer to P. bordai than to any other Phyllodactylus. Clade II comprises P. nocticolus and all species closer to P. nocticolus than to any other Phyllodactylus. Clade III comprises P. tuberculosus and all species closer to P. tuberculosus than to any other Phyllodactylus. Analyses estimate the age for the most recent common ancestor of Phyllodactylus in the Eocene (~43 mya), and the ancestors of each major clade date to the Eocene-Oligocene transition (32–36 mya). This group includes one late-Eocene lineage (P. bordai), Oligocene lineages (P. paucituberculatus, P. delcampi), but also topological patterns that indicate a recent radiation occurred during the Pleistocene on islands in the Gulf of California. The wide spatial and temporal scale indicates a complex and unique biogeographic history for each major clade. The 33 species delimited by BPP and stepping-stone BFD*coalescent based genomic approaches reflect this history. This diversity delimited for Mexican leaf-toed geckos demonstrates a vast underestimation in the number of species based on morphological data alone.

Thermal ecophysiology of a native and an invasive gecko species in a tropical dry forest of Mexico.

For ectotherms, thermal physiology plays a fundamental role in the establishment and success of invasive species in novel areas and, ultimately, in their ecological interactions with native species. Invasive species are assumed to have a greater ability to exploit the thermal environment, higher acclimation capacities, a wider thermal tolerance range, and better relative performance under a range of thermal conditions. Here we compare the thermal ecophysiology of two species that occur in sympatry in a tropical dry forest of the Pacific coast of Mexico, the microendemic species Benedetti's Leaf-toed Gecko (Phyllodactylus benedettii) and the invasive Common House Gecko (Hemidactylus frenatus). We characterized their patterns of thermoregulation, thermoregulatory efficiency, thermal tolerances, and thermal sensitivity of locomotor performance. In addition, we included morphological variables and an index of body condition to evaluate their effects on the thermal sensitivity of locomotor performance in these species. Although the two species had similar selected temperatures and thermal tolerances, they contrasted in their thermoregulatory strategies and thermal sensitivity of locomotor performance. Hemidactylus frenatus had a higher performance than the native species, P. benedettii, which would represent an ecological advantage for the former species. Nevertheless, we suggest that given the spatial and temporal limitations in habitat use of the two species, the probability of agonistic interactions between them is reduced. We recommend exploring additional biotic attributes, such as competition, behavior and niche overlap in order assess the role of alternative factors favoring the success of invasive species.

Population Size and Dynamics of the Lima Leaf-Toed Gecko, Phyllodactylus sentosus, in One of Its Last Refuges

Abstract The Peruvian endemic Lima Leaf-Toed Gecko (Phyllodactylus sentosus) is a critically endangered species with just a few known localities of occurrence, which are isolated from each other, w...