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Bacon C, Look S, Gutiérrez-Pinto N, Antonelli A, Tan H, Kumar P et al. (2016)
Botanical Journal of the Linnean Society.
Four species are recognized in the understorey palm genus Johannesteijsmannia (Arecaceae), all of which occur in close geographical proximity in the Malay Peninsula. We hypothesize that overlapping distributions are maintained by a lack of gene flow among species and that segregation along morphological trait or environmental axes confers ecological divergence and, hence, defines species limits. Although some species have sympatric distributions, differentiation was detected among species in morphological and genetic data, corroborating current species delimitation. Differences in niche breadth were not found to explain the overlapping distribution and co-existence of Johannesteijsmannia spp. Four species formed over the last 3 Mya, showing that diversity accumulated within a short time frame and wide range expansion has not occurred, potentially due to a lack of time for dispersal or the evolution of traits to facilitate movement. An assessment of genetic diversity is presented and, as expected, the widest distribution in the genus harbours the highest genetic diversity.
Keywords: Malesia, Palmae, niche, phylogenetics, speciation
Huang D, Hoeksema B, Affendi Y, Ang P, Chen C, Huang H et al. (2016)
Biodiversity and Conservation.
The South China Sea in the Central Indo-Pacific is a large semi-enclosed marine region that supports an extraordinary diversity of coral reef organisms (including stony corals), which varies spatially across the region. While one-third of the world’s reef corals are known to face heightened extinction risk from global climate and local impacts, prospects for the coral fauna in the South China Sea region amidst these threats remain poorly understood. In this study, we analyse coral species richness, rarity, and phylogenetic diversity among 16 reef areas in the region to estimate changes in species and evolutionary diversity during projected anthropogenic extinctions. Our results show that richness, rarity, and phylogenetic diversity differ considerably among reef areas in the region, and that their outcomes following projected extinctions cannot be predicted by species diversity alone. Although relative rarity and threat levels are high in species-rich areas such as West Malaysia and the Philippines, areas with fewer species such as northern Vietnam and Paracel Islands stand to lose disproportionately large amounts of phylogenetic diversity. Our study quantifies various biodiversity components of each reef area to inform conservation planners and better direct sparse resources to areas where they are needed most. It also provides a critical biological foundation for targeting reefs that should be included in a regional network of marine protected areas in the South China Sea
Keywords: IUCN Red List, Marine biodiversity, Phylogenetic diversity, Rarity, Scleractinia, Species richness
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
Diesmos AC, Watters JL, Huron NA, Davis DR, Alcala AC, Crombie RI, Afuang LE, Gee-Das G, Sison RV, Sanguila MB, Penrod ML, Labonte MJ, Davey CS, Leone EA, Diesmos ML, Sy EY, Welton LJ B (2015)
Proceedings of the California Academy of Sciences 62(20) 457-539.
The herpetological fauna of the Philippines Islands is high in diversity and endemism, yet faces threats suc as habitat modification and loss, natural catastrophes, invasive speciesm hunting for food or the pet trade, and the spread of chytrid fungus. New species descriptions have been steadily rising since the early 1990s due to the increased sampling, an aareness of species boundaries based on phylogenetic studies, and changes in our understanding of what definesa species. Developing a complete species list for amphibians is essential for conservation planning and informed management decisions. Previous lists were derived in part from working compendiums, developed and distributed separately by RIC and ACD; these simpe lists focused on taxonomic and conservation status of the included species, respectively, but were of limited us for other purposes.
Keywords: Entomology, Infectious Diseases, Parasitology, Tropical Medicine
Ningthoujam S, Choudhury M, Potsangbam K, Chetia P, Nahar L, Sarker S et al. (2014)
Phytochemical Analysis 25(6) 495-507.
INTRODUCTION: Sharing traditional knowledge with the scientific community could refine scientific approaches to phytochemical investigation and conservation of ethnomedicinal plants. As such, integration of traditional knowledge with scientific data using a single platform for sharing is greatly needed. However, ethnomedicinal data are available in heterogeneous formats, which depend on cultural aspects, survey methodology and focus of the study. Phytochemical and bioassay data are also available from many open sources in various standards and customised formats. OBJECTIVE: To design a flexible data model that could integrate both primary and curated ethnomedicinal plant data from multiple sources. MATERIALS AND METHODS: The current model is based on MongoDB, one of the Not only Structured Query Language (NoSQL) databases. Although it does not contain schema, modifications were made so that the model could incorporate both standard and customised ethnomedicinal plant data format from different sources. RESULTS: The model presented can integrate both primary and secondary data related to ethnomedicinal plants. Accommodation of disparate data was accomplished by a feature of this database that supported a different set of fields for each document. It also allowed storage of similar data having different properties. CONCLUSION: The model presented is scalable to a highly complex level with continuing maturation of the database, and is applicable for storing, retrieving and sharing ethnomedicinal plant data. It can also serve as a flexible alternative to a relational and normalised database. Copyright © 2014 John Wiley & Sons, Ltd.
Keywords: ethnomedicinal plants, mongodb, nosql databases
Polgar G, Zane L, Babbucci M, Barbisan F, Patarnello T, Rüber L et al. (2014)
Phylogeography and demographic history of two widespread Indo-Pacific mudskippers (Gobiidae: Periophthalmus)
Molecular Phylogenetics and Evolution 73 161-176.
This study provides a first description of the phylogeographic patterns and evolutionary history of two species of the mudskipper genus Periophthalmus. These amphibious gobies are distributed throughout the whole Indo-Pacific region and Atlantic coast of Africa, in peritidal habitats of soft-bottom coastal ecosystems. Three sequence datasets of two widely distributed species, Periophthalmus argentilineatus and P. kalolo, were obtained by amplifying and sequencing two mtDNA markers (D-loop and 16S rDNA) and the nDNA rag1 region. The three datasets were then used to perform phylogeographic, demographic and population genetic analyses. Our results indicate that tectonic events and past climatic oscillations strongly contributed to shape present genetic differentiation, phylogeographic and demographic patterns. We found support for the monophyly of P. kalolo, and only shallow genetic differentiation between East-African and Indo-Malayan populations of this species. However, our collections of the morphospecies P. argentilineatus include three molecularly distinct lineages, one of them more closely related to P. kalolo. The presence of Miocenic timings for the most recent common ancestors of some of these morphologically similar clades, suggests the presence of strong stabilising selection in mudskippers' habitats. At population level, demographic analyses and palaeoecological records of mangrove ecosystems suggest that Pleistocene bottlenecks and expansion plus secondary contact events of the studied species were associated with recurrent sea transgressions during interglacials, and sea regressions or stable regimes during glacials, respectively.
Keywords: Bayesian analyses, Fish morphology, Mangrove habitat, Molecular evolution, Periophthalmus argentilineatus, Periophthalmus kalolo
Wijedasa, L., Shee, Z. Q., Chia E (2014)
Conservation status and lectotypfication of Alangium ridleyi (Cornaceae) in Singapore | Lahiru Wijedasa - Academia.edu
Gardens’ Bulletin Singapore 66(2) 233 - 239.
Alangium ridleyi King is lectotypied and the conservation status updated from Nationally Extinct to Endangered in Singapore and Endangered in Peninsula Malaysia
Keywords: Alangium ridleyi King, Endangered, lectotypicatio
Polgar G, Jaafar Z, Konstantinidis P (2013)
A New Species Of Mudskipper, Boleophthalmus Poti (Teleostei: Gobiidae: Oxudercinae) From The Gulf Of Papua, Papua New Guinea, And A Key To The Genus
The Raffles Bulletin of Zoology 61(1) 311-321.
Boleophthalmus poti, new species, is described from the Gulf of Papua, Papua New Guinea. It is distinguished from its congeners by a combination of characters, including: un-notched, fl attened and horizontally disposed dentary teeth; pelvic-disc length ~10% of SL; D1 base length ~15% of SL; D2 base length ~40% of SL; ~5 interdorsal scale rows; ~110 lateral-scale rows; and the shape and colour pattern of the fi rst and second dorsal fi ns.
Keywords: amphibious gobies, boleophthalmus, fly river delta, oxudercine gobies, taxonomy
Record S, Charney N, Zakaria R, Ellison A (2013)
Ecosphere 4(3) art34.
Given the multitude of ecosystem services provided by mangroves, it is important to understand their potential responses to global climate change. Extensive reviews of the literature and manipulative experiments suggest that mangroves will be impacted by climate change, but few studies have tested these predictions over large scales using statistical models. We provide the first example of applying species and community distribution models (SDMs and CDMs, respectively) to coastal mangroves worldwide. Species distributions were modeled as ensemble forecasts using BIOMOD. Distributions of mangrove communities with high species richness were modeled in threeways: as the sum of the separate SDM outputs, as binary hotspots (with .3 species) using a generalized linear model, and continuously using a general boosted model. Individual SDMs were projected for 12 species with sufficient data and CDMs were projected for 30 species into 2080 using global climate model outputs and a range of sea-level rise projections. Species projected to shift their ranges polewards by at least 2 degrees of latitude consistently experience a decrease in the amount of suitable coastal area available to them. Central America and the Caribbean are forecast to lose more mangrove species than other parts of the world.We found that the extent and grain size, at which continuous CDMoutputs are examined, independent of the grain size at which the models operate, can dramatically influence the number of pseudo-absences needed for optimal parameterization. The SDMs and CDMs presented here provide a first approximation of how mangroves will respond to climate change given simple correlative relationships between occurrence records and environmental data. Additional, precise georeferenced data on mangrove localities and concerted efforts to collect data on ecological processes across large-scale climatic gradients will enable future research to improve upon these correlative models.
Keywords: climate envelope, community, global, mangal, sea-level rise, species richness
Harris J, Yong D, Sheldon F, Boyce A, Eaton J, Bernard H et al. (2012)
Using diverse data sources to detect elevational range changes of birds on Mount Kinabalu, Malaysian Borneo
The Raffles Bulletin of Zoology(25) 197-247.
Few empirical studies have measured the effects of climate change on tropical biodiversity, and this paucity has contributed to uncertainty in predicting the severity of climate change on tropical organisms. With regards to elevational changes, most studies have either re-sampled historical systematic survey sites or analyzed time series of occurrence data at long-term study sites. Such data sources are unavailable for most tropical mountains, so other methods of detecting elevational changes must be sought. Here we combine data from published checklists, recent fi eld work, peer-reviewed literature, unpublished reports, birdwatchers’ trip reports, databases of birdwatchers’ observations, audio recordings, and photographs to compare historical (pre-1998) and current (post-2006) bird distributions on Mt. Kinabalu in Sabah, Malaysian Borneo. Records were carefully checked by experts on Bornean birds. More species are now known from Mt. Kinabalu, but historical data provided elevational range estimates for more species than current data because of extensive mountain-wide collections and surveys. Most elevational comparisons for this study had to be limited to the 1450–1900 m elevational band, where most of the recent work has been done. Information was compiled into an annotated list of 342 species from 200–4095 m. We present this list to encourage refi nement of the dataset and future work on elevational distributions on the mountain. Of 58 species with suffi cient data from 1450 m to the summit, 38 appear to have shifted their ranges (24 species upslope and 14 downslope). A total of 22 resident species have recently been observed above their published maximum elevation for Borneo. Some species that have shifted upwards, such as Chalcophaps indica and Pellorneum pyrrogenys, are now common or breeding at elevations above their published maximum. Fifteen species appear to have declined on the mountain, probably as a result of habitat loss outside the protected area. Several of the upslope shifts are probably attributable to climate change, but many downslope shifts may be artifacts of incomplete recent sampling. The upward shifts agree with the few other tropical range comparisons that have been published. Our approach demonstrates the viability of combining diverse data sources (of varying accuracy and bias) to detect distributional shifts from climate change.
Keywords: checklist, citizen science, climate change, habitat loss, range limit