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Wildlife trade has been considered one of the largest threats to biodiversity in Southeast Asia. Many vertebrates, such as pangolins, elephants and turtles have been heavily hunted as a result of high demand from emerging markets in China and other countries in the region. In Vietnam, over-exploitation of turtles over several decades to supply the international trade has extirpated numerous populations and driven several species to the brink of extinction. To reverse this trend, conservation measures, such as re-introduction of confiscated or captive-bred animals to their native habitats, should be implemented to recover severely declined local populations. For species with a complex phylogeographic structure, however, it is crucial to understand geographic patterns of genetically-distinct populations to avoid releasing animals of unknown origin to wrong localities. In this study, we investigate the phylogeographic pattern of the Four-eyed Turtle (Sacalia quadriocellata), a widely traded species, which occurs in southern China, northern and central Laos and much of Vietnam, using samples with known localities and those collected from the local trade. Our range-wide phylogenetic and network study, based on the complete mitochondrial cytochrome b gene, recovered at least three major clades and seven subclades within the species range. Amongst these, two subclades, one from northern Annamites, Vietnam and the other from north-eastern Laos, are newly discovered. The fine scale phylogeographic analysis helped us to assign misidentified sequences from GenBank and those from confiscated animals with unknown origin to well-defined geographic populations. The results highlight the importance of incorporating samples collected from the local trade and the wild in genetic analyses to support both ex-situ and in-situ conservation programmes of highly-threatened species in accordance with the IUCN’s One Plan Approach.

We record two species of amphibians for the first time from Vietnam: Bufo luchunnicus from Lao Cai and Son La provinces and Amolops wenshanensis from Quang Ninh Province. Morphologically, the Vietnamese representatives of B. luchunnicus resemble the type series from China. The specimen of A. wenshanensis from Vietnam slightly differs from the type series from China by having a smaller size (SVL 33.2 mm vs. 35.7 – 39.9 mm in males) and the presence of distinct transverse bands on the dorsal surfaces of limbs. Genetic divergence between the sequence of the Vietnamese specimen and those of A. wenshanensis from China available from GenBank is 1.2 – 1.6% (ND2 gene). In addition, morphological data and natural history notes of aforementioned species are provided from Vietnam.

A new species of Xenophrys is described from Truong Son Range in Central Vietnam based on morphological and molecular differences. The new species is distinguishable from its congeners by a combination of the following characters: Size medium (SVL 58.8–71.4 mm in males, 65.6–87.3 mm in females); tympanum distinct; vomerine teeth present; tongue notched posteriorly; external vocal sac absent; toes with rudimentary webbing; subarticular tubercles absent, lateral fringes narrow along toes; nuptial pads absent in males; dorsal skin of body with weak granules; flank with small tubercles; dorsum with a dorsal ridge in >-< shape; dorsolateral folds prominent; dorsal surface from reddish brown to grayish brown with a brown triangle between the eyes, and a dark brown marking edged along dorsal ridge on the back; and small white spots present on flank and back of thigh. In the phylogenetic analyses, the new species is nested within the genus Xenophrys with interspecific uncorrected genetic p-distances (16S rRNA gene) from 2.2–2.8% (compared with Xenophrys maosonensis) to 14.4–14.7% (compared with Xenophrys yeae).

Climate change has potential effects on global biodiversity by shifting the optimal distribution of terrestrial organisms, particularly species with narrow distributions. Goniurosaurus lichtenfelderi, a forest-dwelling lizard, is found on both the islands and mainland of northern Vietnam and southern China. The species is categorized as Vulnerable in the IUCN Red List and was recently listed in CITES Appendix II and the Vietnam Government’s Decree 06 in 2019 due to severe anthropogenic impacts on its populations. In this study, we employ Maxent species distribution modeling with climatic and vegetation cover data to identify the potential distribution of G. lichtenfelderi. We also used this approach to assess future climate impacts on the potential distribution under different climate change scenarios. Our model predicts that the potential distribution of G. lichtenfelderi will shrink significantly under future scenarios and even vanish in the entire study area under novel environmental conditions of the BCC-CSM 1-1 – RCP 8.5 scenario by the 2070s. Overall, the current potential distribution is expected to shift towards higher latitudes within the next decades. The forecasted maps provide useful guidelines to implement conservation strategies to mitigate synergistic impacts from climate change and other negative anthropogenic activities. In the context of the potentially severe impacts, the border areas between China and Vietnam, Yen Tu Mountain Range, Bai Tu Long National Park, and their surroundings should be considered core refugia for the species, where conservation measures need to be prioritized in the future.

Madagascar’s unique biota is heavily affected by human activity and is under intense threat. Here, we review the current state of knowledge on the conservation status of Madagascar’s terrestrial and freshwater biodiversity by presenting data and analyses on documented and predicted species-level conservation statuses, the most prevalent and relevant threats, ex situ collections and programs, and the coverage and comprehensiveness of protected areas. The existing terrestrial protected area network in Madagascar covers 10.4% of its land area and includes at least part of the range of the majority of described native species of vertebrates with known distributions (97.1% of freshwater fishes, amphibians, reptiles, birds, and mammals combined) and plants (67.7%). The overall figures are higher for threatened species (97.7% of threatened vertebrates and 79.6% of threatened plants occurring within at least one protected area). International Union for Conservation of Nature (IUCN) Red List assessments and Bayesian neural network analyses for plants identify overexploitation of biological resources and unsustainable agriculture as the most prominent threats to biodiversity. We highlight five opportunities for action at multiple levels to ensure that conservation and ecological restoration objectives, programs, and activities take account of complex underlying and interacting factors and produce tangible benefits for the biodiversity and people of Madagascar.

A new species of the Gekko (Japonigekko) japonicus group from Khammouane Province, central Laos is described based on morphological characters and molecular evidence. Morphologically, Gekko khunkhamensis sp. nov. can be distinguished from the remaining congeners by a combination of the following characters: size moderate (SVL 69.7–75.2 mm); nares in contact with rostral; internasals absent; postmentals enlarged; interorbital scales between anterior corners of the eyes 31 or 32; dorsal tubercles absent; ventrals between mental and cloacal slit 181–185; midbody scales 127–138; ventral scales 42–45; subdigital lamellae on first toe 13 or 14, on fourth toe 14 or 15; tubercles on upper surface of fore and hind limbs absent; precloacal pores absent in the male and females; postcloacal tubercles 2; tubercles absent on dorsal surface of tail base; subcaudals distinctly enlarged; dorsal surface of body with five dark grey bands, which become irregular posteriorly. Genetically, the new species is placed in a clade, consisting of G. bonkowskii, G. nadenensis, G. scientiadventura, G. sengchanthavongi, and G. thakhekensis and differs from other congeners by at least 13% in terms of pairwise distance based on a fragment of the mitochondrial ND2 gene.

A new rhacophorid species is described from Vietnam on the basis of nine specimens collected in Quan Ba District, Ha Giang Province, northeastern Vietnam. The new species is morphologically similar...

The possibility of 3D printing high temperature and chemically resistant polymers creates opportunities for applications in flow chemistry. Herein we describe the development of milli- and microfluidic reactors made of polyether ether ketone (PEEK) with a high temperature 3D printer and examine their mixing performance and suitability for flow reactions at elevated temperatures. Additionally, we present a 3D-printed separator, back pressure regulator and continuous syringe pump, which provide a complete flow system for a fraction of the cost of commercially available flow equipment. Different 3D printed mixing geometries were tested and the influence of mixing on fluorination of a ribose derivative was evaluated. To demonstrate the usability of our self-made flow equipment we performed a multistep reaction of a ribose derivative in excellent yield which could be used as a precursor for the synthesis of nucleoside anti-cancer drugs.

A new species of the genusLycodonis described from Cao Bang Province, Vietnam, based on three individuals with distinct differences in morphology and molecular data. The new species is differentiated from its congeners by a combination of the following characters: dorsal scales in 17-17-15 rows, smooth throughout; supralabials usually eight (rarely nine); infralabials ten; one elongated loreal on each side, in contact with the eye; precloacal plate single; ventral scales 212–218 (plus one or two preventral scales); subcaudals 90 or 91; maxillary teeth 13 or 14; dorsal surface of body with 28 or 29 light body bands; dorsal surface of tail with 13 cream bands, forming a distinct blotch in the vertebral region. Based on phylogenetic analyses of mitochondrial cytochromebsequence data, the new species is recovered as the sister species to a clade containingL. multizonatusandL. liuchengchaoiwith strong support from the Bayesian analysis. The new species is at least 7.5% divergent from other species within this clade in uncorrected pairwise distance calculated using a fragment of more than 1000 bp of the mitochondrial cytochromeb.This discovery increases the number ofLycodonspecies known from Vietnam to 16.

Collaborative SLAM enables a group of agents to simultaneously co-localize and jointly map an environment, thus paving the way to wide-ranging applications of multi-robot perception and multi-user AR experiences by eliminating the need for external infrastructure or pre-built maps. This article presents COVINS, a novel collab- orative SLAM system, that enables multi-agent, scalable SLAM in large environments and for large teams of more than 10 agents. The paradigm here is that each agent runs visual-inertial odomety independently onboard in order to ensure its autonomy, while shar- ing map information with the COVINS server back-end running on a powerful local PC or a remote cloud server. The server back- end establishes an accurate collaborative global estimate from the contributed data, refining the joint estimate by means of place recog- nition, global optimization and removal of redundant data, in order to ensure an accurate, but also efficient SLAM process. A thorough evaluation of COVINS reveals increased accuracy of the collab- orative SLAM estimates, as well as efficiency in both removing redundant information and reducing the coordination overhead, and demonstrates successful operation in a large-scale mission with 12 agents jointly performing SLAM., 2021 IEEE International Symposium on Mixed and Augmented Reality Adjunct (ISMAR-Adjunct), ISBN:978-1-6654-1298-8, ISBN:978-1-6654-1299-5

A new species of the Cyrtodactylus irregularis group is described from Ninh Thuan Province, southern Vietnam based on molecular divergence and morphological differences. Cyrtodactylus orlovi sp. nov. is distinguished from the remaining Indochinese bent-toed geckos by having the unique combination of the following characters: size medium (SVL 61.0–77.7 mm); dorsal tubercles in 16–20 irregular rows; 36–39 ventral scale rows; precloacal pores absent in females, 5 or 6 in males, in a continuous row; femoral pores absent; 3–8 enlarged femoral scales; postcloacal spurs 1 or 2; lamellae under toe IV 16–19; a continuous neckband; a highly irregular transverse banded dorsal pattern; the absence of transversely enlarged median subcaudal scales. In phylogenetic analyses, the new species was revealed to be the sister taxon to a clade consisting of Cyrtodactylus cattienensis and the most recently described species from Vietnam, C. chungi, with 12.1–12.4% and 11.7 % pairwise genetic divergence from the two species, respectively, based on a fragment of the mitochondrial COI gene.

A new species of the genus Cyrtodactylus is described from Dien Bien Province, northwestern Vietnam based on morphological and molecular data. Cyrtodactylus ngati sp. nov. can be distinguished from remaining congeners by the following combination of characters: maximum SVL 69.3 mm; dorsal pattern consisting of six dark irregular transverse bands between limb insertions; inter-supranasals one; dorsal tubercles present on occiput, body, hind limbs and on first half of tail; 17–22 irregular dorsal tubercle rows at midbody; lateral folds clearly defined, with interspersed tubercles; 32–38 ventral scales between ventrolateral folds; 13 precloacal pores separated by a diastema of 5/5 poreless scales from a series of 7/7 femoral pores in enlarged femoral scales; precloacal and femoral pores absent in females; 1–3 postcloacal tubercles on each side; transversely enlarged median subcaudal scales absent. In the molecular analyses, the new species is shown to be the sister taxon to C. interdigitalis from Thailand. This is the 47th species of the genus Cyrtodactylus and the first member of the C. brevipalmatus species group recorded from Vietnam.

Our knowledge of the conservation status of reptiles, the most diverse class of terrestrial vertebrates, has improved dramatically over the past decade, but still lags behind that of the other tetrapod groups. Here, we conduct the first comprehensive evaluation (~92% of the world’s ~1,714 described species) of the conservation status of skinks (Scincidae), a speciose reptile family with a worldwide distribution. Using International Union for Conservation of Nature (IUCN) criteria, we report that ~20% of species are threatened with extinction, and nine species are Extinct or Extinct in the Wild. The highest levels of threat are evident in Madagascar and the Neotropics, and in the subfamilies Mabuyinae, Eugongylinae and Scincinae. The vast majority of threatened skink species were listed based primarily on their small geographic ranges (Criterion B, 83%; Criterion D2, 13%). Although the population trend of 42% of species was stable, 14% have declining populations. The key threats to skinks are habitat loss due to agriculture, invasive species, and biological resource use (e.g., hunting, timber harvesting). The distributions of 61% of species do not overlap with protected areas. Despite our improved knowledge of the conservation status of the world’s skinks, 8% of species remain to be assessed, and 14% are listed as Data Deficient. The conservation status of almost a quarter of the world’s skink species thus remains unknown. We use our updated knowledge of the conservation status of the group to develop and outline the priorities for the conservation assessment and management of the world’s skink species.

The genus Goniurosaurus (tiger geckos) currently consists of 23 species distributed in China, Japan and Vietnam. Several species complexes and recent discoveries of cryptic species pose challenges to the species identification, which is crucial to effectively implement the recent listing of the species from China and Vietnam in CITES Appendix II and the species from Japan in CITES Appendix III. Based on the results of our field work in northern Vietnam and data compiled from literature, we herein provide a taxonomic review of the genus Goniurosaurus. Our phylogenetic analyses showed that all recorded populations of tiger geckos from Vietnam, which were found to be monophyletic with low intra-specific genetic divergences, are assigned to one of the four species: G. catbaensis, G. huuliensis, G. lichtenfelderi or G. luii. Both genetic and morphological analyses confirm that the species from China and Vietnam can be split into three major groups. Based on the newly collected data, we provide an extended morphological description of the Vietnamese species. In addition, we provide an identification key for all Goniurosaurus species from China, Japan and Vietnam in order to assist authorities in the enforcement of the recent CITES listing.

A new species of the gekkonid genus Dixonius is described from Huaysorn-Huaysua village, Nasaithong District, Vientiane Capital, Laos. The new species can be distinguished from all other species by a combination of the following characters: maximum SVL 47.1 mm; 19–21 longitudinal rows of dorsal tubercles at midbody; 23–26 longitudinal rows of ventrals across the abdomen; 7 or 8 supralabials, 6 in mid-orbital position; 5 or 6 infralabials; 5 or 6 precloacal pores in males, femoral pores lacking; precloacal and femoral pores absent in females; a canthal stripe running from rostrum through the eye and terminating at back of head; dorsum brown with irregular dark marks. In phylogenetic analyses, the species is recovered as the sister taxon to D. siamensis, which occurs in Laos, Thailand, and Vietnam. Genetically, the two species are approximately 9.4% divergent from each other based on the complete mitochondrial ND2 gene with six partial or complete adjacent tRNAs. It is the 12th species known in the genus Dixonius and the second Dixonius species described from Laos.

A new species of the genus Vietnamophryne is described from Vu Quang National Park in North Vietnam based on molecular phylogenetic and morphological analyses. The new species is morphologically distinct from congeners and can be easily distinguished from all other members of the genus Vietnamophryne by (1) body size males (n=4) 14.12-14.91 mm; females (n=9) 15.15-17.33 mm; (2) dorsal skin shagreened with small flat pustules loosely scattered on back in males, mostly smooth, slightly shagreened posteriorly, lacking enlarged tubercles in females; (3) belly color ivory-lemon to lemon-yellow with weak dark-brown marbling in males, bright lemon-yellow with weak dark-brown marbling in females; (4) tympanum relatively faint, comparatively small, rounded, 5.4-6.0% of SVL in males, 4.8-6.2% of SVL in females; (5) ratio snout length to eye length 119-128% in males, 100-130 % in females; (6) ratio head width to head length 117-124% in males, 110-131% in females; and (7) ratio first finger to second finger 43-49% in males, 44-50% in females. In the phylogenetic analysis the new species revealed to be sister to V. inexpectata, with 4.3-4.6% divergence in the 16SrRNA gene. So far, the new species is only known from the evergreen tropical forests of Vu Quang National Park at an elevation of 966 m a.s.l. This is the third species of Vietnamophryne reported from Vietnam.

Continuously and reliably estimating the relative configuration of robotic swarms in real-time constitutes a core functionality when pursuing the autonomy of such a swarm. Relying on external positioning systems, such as GPS or motion tracking systems, can provide the required information, but significantly limits the generality of an approach. In this letter, we target formation estimation for autonomous flights of swarms of small UAVs, as they pose particularly challenging restrictions on onboard resources, while opening up a large variety of practical scenarios for a multi-robot setup. While state-of-the-art has been addressing efficient formation estimation, scalability remains limited to only very few agents that can be handled in real-time, with the workload of each agent depending on the total number of agents in the swarm. Aiming for scalable multi-robot systems, here we propose a distributed formation estimation approach, where the computational load of each agent is decoupled from the swarm size. This approach is implemented in a setup with minimal communication effort, requiring only ego-motion estimates from each agent and pairwise distance measurements between them, constraining their configuration globally. Evaluations on swarms of up to 49 UAVs demonstrate the power of our approach to handle large swarms, while keeping the computational load bounded for individual agents and requiring only little data exchange between two robots., IEEE Robotics and Automation Letters, 6 (2), ISSN:2377-3766

Assessing the conservation status of a species is strongly dependent upon data on species distribution and abundance. With the emergence of novel methods for species monitoring – such as the use of environmental DNA (eDNA) – monitoring success can be improved at reduced expenditure in the field, particularly in remote regions and terrains where access is difficult or dangerous. The highly endangered crocodile lizard (Shinisaurus crocodilurus Ahl, 1930) inhabits fragmented sites of the remaining evergreen forest with running water systems in a narrow distribution range in southern China and north‐east Vietnam. Crocodile lizards spend most of the day within or above water bodies, which are commonly remote and inaccessible. To monitor recent spatial occurrences, and to confirm the persistence or extinction of previously reported populations (especially in heavily altered habitats), the suitability of using eDNA and quantitative polymerase chain reaction (qPCR) was tested as an alternative method for monitoring this semiaquatic lizard. To assess the accuracy and limitations of this method, eDNA results from the field were compared with eDNA data from mesocosms and census data on the actual abundance of this species in the field. Environmental DNA of the crocodile lizard was detected in all of the positive controls, and in four of six natural sites; thus, all data collected using traditional field surveys were confirmed with eDNA results. eDNA monitoring was found to be a reliable method for assessing the viability of populations; we suggest that it should be developed as a tool for efficient wildlife management, particularly under difficult field and funding conditions.

Species of the genus Hebius Thompson, 1913 with 17 or 19 dorsal scale rows at midbody and an overall dark venter are reviewed, including the two species previously known as Parahelicops annamensis Bourret, 1934 and Pararhabdophis chapaensis Bourret, 1934. Specimens with 17 scale rows are morphologically similar to Hebius venningi (Wall, 1910), which is here redefined based on external morphological characters such as scalation, and dorsal and ventral patterns. Consequently, Natrix nigriventer Wall, 1925 is resurrected from its synonymy with Hebius venningi, whereas Natrix taronensis Smith, 1940, previously considered a subspecies of H. venningi or a full species by some authors but without justification, is here confirmed to full species status. Another group of species, mostly similar in coloration and pattern to the H. venningi group but with 19 dorsal scale rows, includes H. modestus (Günther, 1875), H. deschauenseei (Taylor, 1934) and a new species which is described herein based on specimens from northern Vietnam, southern China and north-eastern Thailand due to distinct morphological differences. We also provide updated taxonomic accounts for the species of this group, including an identification key and distribution maps.