Assessment of the Threat Status of Bent-Toed Geckos (Cyrtodactylus) in Indochina: Implementation of the One Plan Approach

Abstract

Cyrtodactylus is the most diverse genus of the family Gekkonidae, as well as the third-largest vertebrate genus worldwide. In this study, we investigate the diversity, conservation status, and distribution of species within the genus Cyrtodactylus in Indochina. There are 84 species known from the Indochina region (Vietnam, Laos, and Cambodia), representing 22.6% of the global diversity of the genus. The majority (90.5%) of the taxa are endemic, with a significant portion being microendemic and therefore restricted to specific regions. Recent rapid rise in species discoveries has been driven by molecular analyses of morphologically cryptic species. However, many newly described species remain unassessed in terms of their population status, creating a gap in conservation priorities, with up to 34.5% of currently recognized bent-toed geckos remaining unevaluated. Our study also reveals that over half of the currently recognized Cyrtodactylus species (54.8%) are not covered by any protected area, and 85.7% of threatened species lack any protection measure. Moreover, ex-situ conservation efforts, such as conservation breeding, have not been targeted in conservation plans for bent-toed geckos in Indochina, leaving many species being further threatened in the wild. The findings call for a more integrated approach to conservation in line with IUCN's One Plan Approach, to ensure the long-term survival of these species, advocating for improved taxonomic research and comprehensive conservation assessments for the IUCN Red List. Expanding protected areas and initiating ex-situ programmes are essential to ensure the long-term survival of the bent-toed geckos in the region.

Keywords

Cambodia / Cyrtodactylus / discovery rate / endemic species / Laos / protected area / species diversity / threat analysis / Vietnam

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2025 The Author(s). Integrative Conservation published by John Wiley & Sons Australia, Ltd on behalf of Xishuangbanna Tropical Botanical Garden (XTBG).