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21.
The monotypic genus Hormiops Fage, 1933 is so far only known from two groups of granitic islands off the coasts of Peninsular Malaysia and Vietnam. Examination of newly collected material from both archipelagos and of the type series of Hormiops davidovi Fage, 1933 reveals previously disregarded morphological differences sufficient to assign the Malaysian specimens to a distinct species, described here as Hormiops infulcra sp. nov. An updated diagnosis of the genus, as well as a dichotomic key enabling the determination of Hormiops from its close relatives, Hormurus Thorell, 1876 and Liocheles Sundevall, 1833 are also provided. The phylogenetic position, distribution pattern, and ecology of these insular scorpions suggest that they are palaeoendemics, remnants of a previously more widely distributed lineage. A biogeographical model is proposed for the genus based on these observations and on a synthesis of palaeogeographical and palaeoenvironmental data currently available for Sundaland.  相似文献   
22.
Background: Genetic divergence is one of the key processes in speciation. In the Begoniaceae, genetic divergence caused by limited gene flow may explain its high species diversity and endemicity. This hypothesis has been supported by past genetic work but there is a lack of empirical studies on the causes of limited gene flow.

Aim: To identify the causes of limited gene flow in Begonia.

Methods: We examined the genetic structure among the populations of Begonia maxwelliana at the macro- and micro-spatial scales using microsatellites, measured seed dispersal range and observed flowering phenology.

Results: Population differentiation and structuring were detected at both the macro- and micro-scales. Dispersal range was short, and all populations showed similar reproductive behaviour.

Conclusions: The strong population differentiation and structuring among the populations studied imply that they are evolutionarily significant units and possible candidates for speciation. Geographical barriers and limited seed dispersal restrict gene flow in the populations, and these factors may be responsible for the rapid speciation and large diversity in the family.  相似文献   

23.
Bovine anaplasmosis is a major concern to cattle farming in most parts of the world. Anaplasmosis negatively impacts the profitability of cattle farming by reducing the production, reproduction, and draft ability of cattle. Here, we report results from a one-year cross sectional study to determine the epidemiology and the risk factors for Anaplasma marginale infection of cattle in Peninsular Malaysia. Examination of one thousand and forty five blood samples of apparently healthy cattle from forty-three farms in all the states of Peninsular Malaysia by polymerase chain reaction (PCR) assay revealed an overall prevalence of A. marginale infection of cattle of 72.6%, showing high endemicity of this heamoprotozoan among cattle in the country. Cattle breeds, production type, herd owner, herd size, management system, farm size, farm age, prophylactic treatment against blood parasites, presence of ticks, frequency of deticking, zones, closeness to forest, closeness to waste area, closeness to human settlement and closeness to body of water were the risk factors significantly associated (P?<?0.05) with the detection of A. marginale in cattle. Results of this first molecular study on the epidemiology and risk factors for A. marginale infection of cattle from all the states of Peninsular Malaysia suggest policies and strategies for the prevention and control of the parasite to improve profitability of cattle farming in the country.  相似文献   
24.
25.
Epidemiological study on strongyloidiasis in humans is currently lacking in Malaysia. Thus, a cross-sectional study was carried out to determine the prevalence of Strongyloides stercoralis infection among the inhabitants of longhouse indigenous communities in Sarawak. A single stool and blood sample were collected from each participant and subjected to microscopy, serological and molecular techniques. Five species of intestinal parasites were identified by stool microscopy. None of the stool samples were positive for S. stercoralis. However, 11% of 236 serum samples were seropositive for strongyloidiasis. Further confirmation using molecular technique on stool samples of the seropositive individuals successfully amplified 5 samples, suggesting current active infections. The prevalence was significantly higher in adult males and tended to increase with age. S. stercoralis should no longer be neglected in any intestinal parasitic survey. Combination of more than 1 diagnostic technique is necessary to increase the likelihood of estimating the ‘true’ prevalence of S. stercoralis.  相似文献   
26.
Cryptosporidium, a protozoan parasite, can cause cryptosporidiosis which is a gastrointestinal disease that can infect humans and livestock. Cattle are the most common livestock that can be infected with this protozoan. This study was carried out to determine the prevalence of Cryptosporidium infection in cattle in Kuantan, Pahang, Malaysia and to find out the association between the occurrence of infection and 3 different ages of cattle (calves less than 1 year, yearling, and adult cattle). The samples were processed by using formol-ether concentration technique and stained by modified Ziehl Neelsen. The results showed that 15.9% (24/151) of cattle were positive for Cryptosporidium oocysts. The occurrence of Cryptosporidium in calves less than 1 year was the highest with the percentage of 20.0% (11/55) followed by yearling and adult cattle, with the percentage occurrence of 15.6 % (7/45) and 11.8% (6/51), respectively. There was no significant association between the occurrence and age of cattle and presence of diarrhea. Good management practices and proper hygiene management must be taken in order to reduce the infection. It is highly important to control the infection since infected cattle may serve as potential reservoirs of the infection to other animals and humans, especially animal handlers.  相似文献   
27.
The reef fisheries of Pulau (meaning “island” in Malay) Banggi, Sabah are not managed, and lack baseline fisheries data despite forming part of a proposed marine park. Thus, a combination of qualitative and quantitative approaches was applied to obtain a baseline picture about the past and present state of the fisheries. Fish landings were monitored, and fisher interviews conducted to investigate seasonal effects and historical changes in Banggi’s reef fisheries. Monsoon winds were a major driver of seasonal differences in catch quantities for the hook and line, but not the gillnet fishery. Spatial distribution of fishing effort and target species also differed by season. Fishers consistently indicated that Banggi’s fisheries were declining, with a suggested three to four times decrease in catch rates over the last 20 years. Interestingly, it appeared that substantial decreases began in the year 2000. The responses of fishers to seasonal changes, and the resultant implications for management are discussed. Importantly, the need for immediate management policies to prevent further declines and to maintain sustainable reef fisheries is stressed. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.
L. S. L. TehEmail:
  相似文献   
28.
Many marine protected areas (MPAs), particularly in developing countries, have failed because of a lack of enforcement and monitoring due to limited public funds for conservation. Private investment and management in MPAs offers a potential solution, and has been applied with initial positive results at the Sugud Islands Marine Conservation Area (SIMCA) in Sabah, Malaysia. Conservation fees charged to visitors to Lankayan Island Dive Resort within the SIMCA have generated a sustainable source of financing to meet the majority of management costs for the conservation area, which is separately managed by a private organization called Reef Guardian. The availability of adequate funds has enabled Reef Guardian to invest in personnel training and surveillance technology to enforce the rules and regulations of the conservation area. In collaboration with government enforcement agencies, Reef Guardian has reduced threats such as illegal fishing and turtle egg poaching. As a result, there is a comparatively high abundance of commercially important fish, and turtle nestings at Lankayan Island have increased. Private management can be effective in conserving biodiversity in MPAs, and may well succeed regionally in suitable locations.
Lydia C. L. TehEmail:
  相似文献   
29.
The large genus Orthomorpha is rediagnosed and is shown to currently comprise 51 identifiable species ranging from northern Myanmar and Thailand in the Northwest to Lombok Island, Indonesia in the Southeast. Of them, 20 species have been revised and/or abundantly illustrated, based on a restudy of mostly type material; further 12 species are described as new: Orthomorpha atypicasp. n., Orthomorpha communissp. n., Orthomorpha isarankuraisp. n., Orthomorpha picturatasp. n., Orthomorpha similanensissp. n., Orthomorpha suberectasp. n., Orthomorpha tuberculiferasp. n.,Orthomorpha subtuberculiferasp. n. and Orthomorpha latitergasp. n., all from Thailand, as well as Orthomorpha elevatasp. n.,Orthomorpha spiniformissp. n. and Orthomorpha subelevatasp. n., from northern Malaysia. The type-species Orthomorpha beaumontii (Le Guillou, 1841) is redescribed in due detail from male material as well, actually being a senior subjective synonym of Orthomorpha spinala (Attems, 1932), syn. n. Two additional new synonymies are proposed: Orthomorpha rotundicollis (Attems, 1937) = Orthomorpha tuberculata (Attems, 1937), syn. n., and Orthomorpha butteli Carl, 1922 = Orthomorpha consocius Chamberlin, 1945, syn. n., the valid names to the left. All species have been keyed and all new and some especially widespread species have been mapped. Further six species, including two revised from type material, are still to be considered dubious, mostly because their paraterga appear to be too narrow to represent Orthomorpha species. A new genus, Orthomorphoidesgen. n., diagnosed versus Orthomorpha through only moderately well developed paraterga, coupled with a poorly bi- or trifid gonopod tip, with at least some of its apical prongs being short spines, is erected for two species: Orthomorpha setosus (Attems, 1937), the type-species, which is also revised from type material, and Orthomorpha exaratus (Attems, 1953), both comb. n. ex Orthomorpha.  相似文献   
30.
Genetic divergence in geographically isolated populations is a prerequisite for allopatric speciation, one of the most common modes of speciation. In ecologically equivalent populations existing within a small, environmentally homogeneous area, an important role for environmentally neutral divergence is often found or inferred. We studied a species complex of conspicuously shaped Opisthostoma land snails on scattered limestone outcrops within a small area of lowland rainforest in Borneo. We used shell morphometrics, mitochondrial and nuclear DNA sequences, and marks of predation to study the factors involved in allopatric divergence. We found that a striking geographic divergence exists in shell morphology, which is partly associated with neutral genetic divergence. We also found geographic differentiation in the behavior of the snails' invertebrate predator and evidence of an evolutionary interaction between aspects of shell shape and predator behavior. Our study shows that adaptation to biotic aspects of the environment may play a more important role in allopatric speciation than previously suspected, even on a geographically very small scale.  相似文献   
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