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Moyes C, Shearer F, Huang Z, Wiebe A, Gibson H, Nijman V et al. (2016)
Predicting the geographical distributions of the macaque hosts and mosquito vectors of Plasmodium knowlesi malaria in forested and non-forested areas.
Parasites & vectors 9(1) 242.
BACKGROUND: Plasmodium knowlesi is a zoonotic pathogen, transmitted among macaques and to humans by anopheline mosquitoes. Information on P. knowlesi malaria is lacking in most regions so the first step to understand the geographical distribution of disease risk is to define the distributions of the reservoir and vector species. METHODS: We used macaque and mosquito species presence data, background data that captured sampling bias in the presence data, a boosted regression tree model and environmental datasets, including annual data for land classes, to predict the distributions of each vector and host species. We then compared the predicted distribution of each species with cover of each land class. RESULTS: Fine-scale distribution maps were generated for three macaque host species (Macaca fascicularis, M. nemestrina and M. leonina) and two mosquito vector complexes (the Dirus Complex and the Leucosphyrus Complex). The Leucosphyrus Complex was predicted to occur in areas with disturbed, but not intact, forest cover (> 60 % tree cover) whereas the Dirus Complex was predicted to occur in areas with 10-100 % tree cover as well as vegetation mosaics and cropland. Of the macaque species, M. nemestrina was mainly predicted to occur in forested areas whereas M. fascicularis was predicted to occur in vegetation mosaics, cropland, wetland and urban areas in addition to forested areas. CONCLUSIONS: The predicted M. fascicularis distribution encompassed a wide range of habitats where humans are found. This is of most significance in the northern part of its range where members of the Dirus Complex are the main P. knowlesi vectors because these mosquitoes were also predicted to occur in a wider range of habitats. Our results support the hypothesis that conversion of intact forest into disturbed forest (for example plantations or timber concessions), or the creation of vegetation mosaics, will increase the probability that members of the Leucosphyrus Complex occur at these locations, as well as bringing humans into these areas. An explicit analysis of disease risk itself using infection data is required to explore this further. The species distributions generated here can now be included in future analyses of P. knowlesi infection risk.
Keywords: Entomology, Infectious Diseases, Parasitology, Tropical Medicine
Arida E, Setyawatiningsih S (2015)
On the occurrence of Varanus nebulosus (Gray, 1831) (Squamata: Varanidae) on Riau Archipelago, Indonesia
Zootaxa 3919(1) 197.
The occurrence of Varanus nebulosus (Gray, 1831) on Sumatra still remains open for debates, while records are limited, especially those associated with a voucher specimen. The oldest record of V. nebulosus that is associated with a specimen, i.e. SMF 11554 is dated back to 1889 and presumably from Bengal (“Bengalen”), which now lies around Bangladesh. The specimen is kept at Senckenberg Museum Frankfurt (SMF) in Germany. We collected specimens from two islands in the Riau Archipelago, just west of Sumatra and provided new distribution data for this protected species of Monitor lizard in Indonesia. The two recent records represent populations of V. nebulosus other than those already known in the literature and are among the closest known occurrences to Sumatra. We suggest that islands in the Riau Archipelago might have been the stepping stones for a historical dispersal of this species from mainland Southeast Asia and Singapore.
Keywords: Squamata, Varanidae
Robiansyah I, Hajar A (2015)
Predicting Current and Future Distribution of Endangered Tree Dracaena ombet Kotschy and Peyr. Under Climate Change
Proceedings of the National Academy of Sciences, India Section B: Biological Sciences.
The endangered tree Dracaena ombet Kotschy and Peyr. (Asparagaceae) is a native of Djibouti, Egypt, Eritrea, Ethiopia, Saudi Arabia, Somalia and Sudan. The tree has been experiencing population decline throughout its native ranges due to overgrazing, attack by pathogens, human overexploitation, and climate change. The conservation actions for this tree are hindered due to poor information on its geographical distribution. Using published occurrence data, current and future distribution of D. ombet under climate change was predicted in the present study using MaxEnt. The model performed better than random with area under the curve and true skill statistical values were 0.979 ± 0.034 and 0.724 ± 0.419, respectively. The tree was predicted to be found on mountain chain around the Red Sea with slope and precipitation being the most influential factors. Future prediction of D. ombet showed major loss of habitat in Djibouti, Egypt, Eritrea, Ethiopia, Somalia and Sudan. In Saudi Arabia, however, most of the population could deal with future climate and some population even could expand their ranges to higher latitude. The results from the present study can be used as a basis for further detailed survey of D. ombet and for planning the conservation actions needed to conserve the species, especially in dealing with future climate change.
Keywords: Climate change, Dracaena ombet, Endangered tree, MaxEnt, Modeling
Setyawan A (2014)
A new record of naturalized Selaginella uncinata (Desv.) Spring (Selaginellaceae) from Java, Indonesia
Biodiversitas 15(2) 261-268.
During extensive field research on the diversity and distribution of Selaginella in Java, between 2007 and 2014, an alien species have been found in nature, i.e. Selaginella uncinata. This species is a trailing herb with small, wiry, creeping main stem, fan-shaped branches, rooting at the nodes to c.a. 100 cm long or more; leaves are dimorphic, 4-ranked, and characterized by conspicuous blue iridescent; strobili are tetragonal, up to c.a. 2 cm long. S. uncinata found growing wild in the highlands with high rainfall, namely: Cibodas Botanical Garden, Cianjur, West Java and Tawangsari, in the city district of Wonosobo, Central Java, Indonesia. Transplant experiments indicate that this plant is able to grow and reproduce well in the lowlands (Depok, 107 m asl.) and the highlands (Wonosobo, 768 m asl.). In the experimental garden, it can compete with native species of Java selaginellas, for space, sunlight and nutrients. Therefore, the invasion ability of this species needs to be concerned.
Keywords: alien, invasive, java, new record, selaginella uncinata
Webb C, Slik J, Triono T (2010)
Biodiversity and Conservation 19(4) 955-972.
Rapidly changing land use in Southeast Asia threatens plant diversity, and reduces the time we have left to document it. Despite over 200 years of scientific plant exploration, many plant species have yet to be discovered. Moreover, we still have a very poor understanding of the distribution of known taxa in this biogeographically complex region. We review the current state of biodiversity exploration, using plants in Indonesia as an example. Traditional methods of collecting and describing species have provided a solid foundation for our understanding of plant biodiversity, but are insufficient for the pragmatic task of rapidly discovering and documenting today’s biodiversity before it is gone, because general collecting expeditions tend to be infrequent, and documentation of most new species must await taxonomic revisions many years in the future. Solutions to this exploration and documentation crisis (i) could use the abundant resource of enthusiastic, networked, national biology students, (ii) should employ biodiversity informatics tools to efficiently engage both specialists and parataxonomists, and (iii) might require adoption of new types of α-taxonomy, utilizing increasingly low-cost molecular methods and high resolution photographs. We describe emerging technologies that will facilitate this taxonomic development. We believe that a new golden age of biodiversity exploration may be dawning, just as biodiversity itself is most threatened, and are hopeful that increasing knowledge of biodiversity will be a positive force to slow its loss.
Keywords: biodiversity, taxonomy