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Sexual head dimorphism is a condition where head morphology of male and female of the same species differ, which provides an additional way to recognise sex for species identification. Fifty four adult Philippine Spotted Flying Lizards, Draco spilopterus, were examined from four populations in the Luzon Island, Philippines to assess whether head morphometry can drive sexual dimorphism. We identified the sex and measured five morphometric measurements of the head (jaw length, jaw width, head height, head length, head width) and snout-vent length. A univariate analysis of the five morphometric measurements showed clear sexual dimorphism. Considering all individuals, female heads are significantly larger than those of males (all p-values < 0.05). We also revealed major differences in head size amongst the four populations due to their geographical location and habitat differences.

The ever‐increasing and expanding globalisation of trade and transport underpins the escalating global problem of biological invasions. Developing biosecurity infrastructures is crucial to anticipate and prevent the transport and introduction of invasive alien species. Still, robust and defensible forecasts of potential invaders are rare, especially for species without known invasion history. Here, we aim to support decision‐making by developing a quantitative invasion risk assessment tool based on invasion syndromes (i.e., generalising typical attributes of invasive alien species). We implemented a workflow based on 'Multiple Imputation with Chain Equation' to estimate invasion syndromes from imputed datasets of species' life‐history and ecological traits and macroecological patterns. Importantly, our models disentangle the factors explaining (i) transport and introduction and (ii) establishment. We showcase our tool by modelling the invasion syndromes of 466 amphibians and reptile species with invasion history. Then, we project these models to amphibians and reptiles worldwide (16,236 species [c.76% global coverage]) to identify species with a risk of being unintentionally transported and introduced, and risk of establishing alien populations. Our invasion syndrome models showed high predictive accuracy with a good balance between specificity and generality. Unintentionally transported and introduced species tend to be common and thrive well in human‐disturbed habitats. In contrast, those with established alien populations tend to be large‐sized, are habitat generalists, thrive well in human‐disturbed habitats, and have large native geographic ranges. We forecast that 160 amphibians and reptiles without known invasion history could be unintentionally transported and introduced in the future. Among them, 57 species have a high risk of establishing alien populations. Our reliable, reproducible, transferable, statistically robust and scientifically defensible quantitative invasion risk assessment tool is a significant new addition to the suite of decision‐support tools needed for developing a future‐proof preventative biosecurity globally. [ABSTRACT FROM AUTHOR]

This study highlights the ecology, natural history, and a new distribution record by providing a unique habitat occurrence record in karst ecosystem and describes a tail anomaly of the endemic Mamanwa Bent-toed Gecko Cyrtodactylus mamanwa in the province of Dinagat. The detection of a new population on Unib Island in the southwestern Dinagat extends the previously known distribution of this gekkonid by approximately 100 km south from its known distribution.

Information on species richness and community structure is invaluable for guiding conservation and management of biodiversity, but is rarely available in the megadiverse biodiversity conservation hotspot of Philippines – particularly for amphibians and reptiles. This study provides the first report and characterisation of amphibians and reptile communities across primary habitat types of the Victoria-Anepahan Mountain Range on Palawan Island along the western edge of the archipelago. A total of 41 amphibian and reptile species were recorded throughout our sampling sites (n = 27 species) or in targeted habitat searches (14 species). A species richness estimator predicted that 35 species may be present in our sampling sites, suggesting that a significant proportion of secretive species may continue to be unrecorded, especially for reptiles. Higher species richness was found in secondary growth than in mixed-use agricultural areas or even pristine forest. The low species richness recorded from pristine forest types may be due to these forests now being restricted to higher elevations where species diversity has been documented to decrease. Our results also show that complex community structures (species assemblages) are to be equally expected in both secondary growth and pristine forests. Together, our results show how species richness and community assemblages may vary across habitats, highlighting that old growth forest does not always support higher species richness, particularly in high elevations.

The island of Mindanao in the southern Philippines has the richest herpetofauna presently documented for any one island in the archipelago, although many regions on the island are yet to be explored. Limestone karst habitats, in particular, are poorly surveyed and are also the most threatened ecosystems in the Philippines. We conducted field surveys on the herpetofauna of Mount Capistrano, a low-elevation limestone karst habitat and an ecotourism destination in the central Mindanao Province of Bukidnon. Our study is the first biodiversity assessment of the area. We recorded a total of 32 species consisting of 10 frogs, nine lizards, and 13 snakes. Nine are Philippine endemic species, whereas seven are found only in the Mindanao faunal region. Three are invasive alien species. We also provide preliminary information on a putative new species of limestone frog of the genus Platymantis. Our study shows that despite disturbance, limestone karst forests in Mindanao harbor significant levels of herpetofaunal species richness, including undiscovered micro-endemics. This study reinforces the biological significance of karst habitats and the critical need to conduct comprehensive biodiversity inventories of this unique, naturally patchily distributed, and highly threatened ecosystem throughout the Philippines. [ABSTRACT FROM AUTHOR]

Once distributed all over the Philippines, the endemic Philippine Crocodile (Crocodylus mindorensis) is nowadays threatened with extinction. It is estimated that less than 140 mature individuals live in the wild. Human activities like fishing and poaching, as well as land-use change and habitat conversion cause a continuing threat to the remaining populations. Therefore, designated protected areas (PAs) were evaluated with species distribution models (SDMs) and also to see if most suitable areas are covered by PAs in order to improve future conservation efforts. For this purpose, the existing IUCN-reserves were analysed for potential habitat suitability (combining bioclimatic and remote sensing variables), wetland occurrences and the human footprint index by using MaxEnt and QGIS. Based on species records, our final SDM showed high performance and revealed the climatically most suitable areas for the species, which were mostly on Luzon and Mindanao. However, only small parts of the climatically suitable wetlands are currently covered by reserves (0.3-46.3%). In addition, none of the species' records was located within a PA. The anthropogenic pressures in the reserves measured by human footprint index (considering eight variables i.e. 'population density', 'navigable waterways', 'crop lands' and 'roads') were diverse and varied between a low and moderate level. Most of the records were found in areas with a moderate human footprint. Considering the three criteria, 'Lake Lanao Watershed Reservation', 'Angat Watershed Forest Reserve District (Metro Water District)', 'Northern Sierra Madre Natural Park', 'Talaytay Protected Landscape' and 'Agusan Marsh Wildlife Sanctuary' revealed to be the most suitable conservation areas for C. mindorensis, whereas suitable areas outside PAs are highly recommended for further surveys. We recommend to declare Ligawasan Marsh, Mindanao as a PA as this area harbours a large population of C. mindorensis. The declaration of more climatically suitable areas with low level of human footprint to PAs is a necessary step for the long-term conservation of this endemic crocodile species. The current network of existing PAs needs improvement in order to provide well-suited and long-term protection for C. mindorensis. More surveys are also necessary to find hidden, so far overlooked populations and to assess C. mindorensis tolerance level for human impacts. [ABSTRACT FROM AUTHOR]

We summarize all available amphibian and reptile species distribution data from the northeast Mindanao faunal region, including small islands associated with this subcenter of endemic vertebrate biodiversity. Together with all publicly available historical information from biodiversity repositories, we present new data from several major herpetological surveys, including recently conducted inventories on four major mountains of northeast Mindanao, and adjacent islands of Camiguin Sur, Dinagat, and Siargao. We present species accounts for all taxa, comment on unresolved taxonomic problems, and provide revisions to outdated IUCN conservation status assessments in cases where our new data significantly alter earlier classification status summaries. Together, our comprehensive analysis of this fauna suggests that the greater Mindanao faunal region possesses distinct subcenters of amphibian and reptile species diversity, and that until this area is revisited and its fauna and actually studied, with on-the-ground field work including targeted surveys of species distributions coupled to the study their natural history, our understanding of the diversity and conservation status of southern Philippine herpetological fauna will remain incomplete. Nevertheless, the northeast Mindanao geographical area (Caraga Region) appears to have the highest herpetological species diversity (at least 126 species) of any comparably-sized Philippine faunal subregion.

We report new distribution records for amphibians and reptiles from 20 localities within the northern Cordillera Mountain Range of Ilocos Norte Province, Luzon Island, Philippines. Together with opportunistic collections of specimens from past surveys, our new data result in a total of 58 amphibian and reptile species for Ilocos Norte Province and the extreme northern Cordilleras—all of which constitute major geographic range extensions. We utilize new data and IUCN formalized conservation assessment criteria to revise the conservation status of many species. Our results highlight the degree to which fundamental distribution data are lacking for Luzon amphibians and reptiles and emphasize the manner in which many current species assessments are based on incomplete data and, as a result, may be sorely misleading. The complex biogeography of Luzon’s herpetofauna remains poorly understood, providing opportunities for future research and conservation efforts once distribution patterns and local abundances are properly documented.

We provide the first report on the herpetological biodiversity (amphibians and reptiles) of the northern Sierra Madre Mountain Range (Cagayan and Isabela provinces), northeast Luzon Island, Philippines. New data from extensive previously unpublished surveys in the Municipalities of Gonzaga, Gattaran, Lasam, Santa Ana, and Baggao (Cagayan Province), as well as fieldwork in the Municipalities of Cabagan, San Mariano, and Palanan (Isabela Province), combined with all available historical museum records, suggest this region is quite diverse. Our new data indicate that at least 101 species are present (29 amphibians, 30 lizards, 35 snakes, two freshwater turtles, three marine turtles, and two crocodilians) and now represented with well-documented records and/or voucher specimens, confirmed in institutional biodiversity repositories. A high percentage of Philippine endemic species constitute the local fauna (approximately 70%). The results of this and other recent studies signify that the herpetological diversity of the northern Philippines is far more diverse than previously imagined. Thirty-eight percent of our recorded species are associated with unresolved taxonomic issues (suspected new species or species complexes in need of taxonomic partitioning). This suggests that despite past and present efforts to comprehensively characterize the fauna, the herpetological biodiversity of the northern Philippines is still substantially underestimated and warranting of further study.