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The Greater Sunda region of South-east Asia supports a rich diversity of economically and ecologically important species. However, human pressures are reshaping contemporary biogeography across the region. Megafaunal distributional patterns have been particularly affected because of deforestation, poaching and human–wildlife conflict. Crocodilians are at the centre of these conflicts in Indonesia and yet remain poorly studied across much of the archipelago. We conducted population surveys of salt-water crocodiles Crocodylus porosus and false gharials Tomistoma schlegelii in Sumatra, and examined whether crocodile abundance and distribution are correlated with variations in human disturbance, fishing pressure, and habitat type. We then used these data to model remaining suitable habitat for T. schlegelii across South-east Asia. We found that abundance of T. schlegelii and C. porosus was correlated with distance from human settlements, and fish-trapping pressure. We recorded the presence of T. schlegelii in a river system in which it was previously unknown, thus expanding the known range of the species. We also found that the predicted remaining suitable habitat for T. schlegelii in Indonesia is largely limited to areas of low human activity. From these empirical and modelling approaches we propose several key conservation priorities: (1) eliminate the use of fish traps in remaining patches of T. schlegelii habitat, (2) prioritize crocodile population surveys in remaining suitable habitat, particularly in remote areas, (3) consider T. schlegelii to be potentially Endangered locally in Sumatra, and (4) expand existing reserves around the Lower Kampar River and Berbak National Park/Sembilang National Park areas of Sumatra. [ABSTRACT FROM AUTHOR]

IUCN Red List assessments are important for conservation and management initiatives. However, status assessments are often challenging because of poor sampling between biogeographical regions. Researchers sometimes assess poorly known species, which can have unforeseen ramifications, including the trade of rare and cryptic species under common species names. Here, we address this issue in relation to economically important reptile species in Indonesia. We reviewed examples of single species categorized as Least Concern for which the assessments probably encompassed multiple closely related species. We also examined Red List assessments that utilized species distribution modelling techniques, and identified biogeography as a major barrier to using such methods. To test how biogeography may affect status assessments we used our own model lizard system from Indonesia, taking an integrative phylogeographical approach to quantify status assessments under contrasting scenarios. We show that failure to account for biogeographical breaks leads to significant variation in Red List status. Our model system fluctuates from Least Concern to Endangered, depending upon whether biogeographical boundaries are considered in taxonomic evaluations. We identify Sauria (lizards) and Serpentes (snakes) as major lineages requiring taxonomic and conservation attention in Indonesia. We also make the following recommendations: (1) Indonesia's trade quotas should further subdivide management zones to account for gaps in taxonomic evaluations; (2) genetic sampling should be considered a high priority during wildlife exportation processes from poorly studied geographical areas; and (3) continuation of thorough biological inventory is critical for conservation initiatives across heterogeneous mountain and island landscapes. [ABSTRACT FROM AUTHOR]

• New Molecular phylogeny of Sumatra's cloud forest Draconinae lizards. • Sumatra's montane Draconinae lizards have deep divergence and allopatric distributions. • Draconinae lizard diversity arose from in situ diversification. • Distributions and divergence estimates may elucidate history of Pleistocene forests. Biogeographical evidence, both, for and against the "regional endemism paradigm" hypothesis has been uncovered across the Greater Sunda Region (Sundaland) of Southeast Asia. Additionally, there are competing hypotheses regarding how Pleistocene forests may have impacted biological patterns and processes in Sumatra. Using montane agamid lizards from Sumatra, we derived and analyzed a phylogenetic dataset, genetic divergence estimates, and contemporary distributional patterns among species. We tested whether (1) Sumatra's highland Draconinae diversification fits the regional endemism paradigm hypothesis and (2) Draconinae phylogeography provides biological evidence for Pleistocene forest extent at various points in history. Our results suggest in situ diversification was the main driver behind montane Draconinae lizard diversification in Sumatra, rejecting the "regional endemism paradigm". Contemporary distribution of endemic species and their genetic relationships may potentially provide biological evidence for determining more precise elevational lower limits of montane forests during the Pleistocene epoch. Our data suggests montane forests did not retreat more than 700–750 m during glacial maxima because lower retreating forests would have become interconnected, allowing for widespread dispersal, exchange of gene flow and sympatric distributions contemporarily. To the contrary, our divergence estimates show that cloud forest dragons have been isolated for millions of years, suggesting there may have been a continuous disconnect between some areas, predating the Pleistocene. There may also be other ecological and evolutionary factors that impacted Draconinae distributions, such as competition, making this an excellent system for testing questions regarding montane biogeography. Additionally, we provide the first phylogeny for a wide range of Sundaland agamid species and identify some biogeographic pressures that may have triggered montane Draconinae diversification in Sumatra. [ABSTRACT FROM AUTHOR]