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1.
Blood cockles are among the most economically important brackish water invertebrates found in Malaysia. However, our knowledge of blood cockle phylogeny and systematics is rudimentary, especially for the species Tegillarca granosa. It is unclear, for instance, whether the cockles occurring on the west coast of peninsular Malaysia constitute a single species, or multiple, phylogenetically distinct species. We performed the first DNA molecular phylogenetic analysis of T. granosa to distinguish it from other related species found in other parts of the world and to create a DNA database for the species. An approximately 585-nucleotide fragment of the mitochondrial DNA (cytochrome oxidase I, COI) was sequenced for 150 individual cockles, representing 10 populations: three from the north, four from the central part and three from the southern part of peninsular Malaysia. Phylogenetic analyses of the resulting dataset yielded tree topologies that not only showed the relationship between T. granosa and its closest relatives but its position in the evolutionary tree. Three mitochondrial clades were evident, each containing an individual genus. Using the mutation rate of the COI gene, the divergence time between T. granosa and its closest related species was estimated to be 460 thousand years ago. This study provides a phylogenetic framework for this ecologically prominent and commercially important cockle species.  相似文献   

2.
Malaysia has approximately 15,000 species of vascular plants. Its flora is distributed between two major geographical regions; Peninsular Malaysia on mainland Asia and the states of Sabah and Sarawak on the island of Borneo. Peninsular Malaysia has over 8,300 plant species and Sabah and Sarawak in a recent estimate have about 12,000 species. Total species endemism for Peninsular Malaysia is about 30%; its tree endemism is 26.3%. For Sabah and Sarawak, the endemism level is higher, recently revised figures gave a tree species endemism of 42.1%. Malaysia has recently published its national strategy for plant conservation, which now forms the basis of conservation activities for the country. Since 2004, we have been running a project entitled “Conservation Monitoring of Rare and Threatened Plants of Peninsular Malaysia”, in which conservation status assessment is scored for a number of families. Results of the assessment of 458 taxa included 46.1% in some threat category. Detailed conservation studies are in progress for 33 species of threatened plants. Initial work on these species include spatial distribution studies at regional level based on herbarium records, and at a more local level, population studies to determine demography of populations. Regular phenological observations were also made for many of the species.  相似文献   

3.
From a study on some aspects of the reproductive biology of the tropical cyprinid Hampala macrolepidota (Van Hasselt) in Zoo Negara Lake, Kuala Lumpur, Malaysia, analyses of the maturity stages, gonadosomatic indices and oocyte diameter patterns show that this fish is able to spawn throughout the year. However, physicochemical and environmental factors determine the actual spawning time of this fish. Spawning activity is associted with decreasing temperatures and daylengths, rising water levels and increasing turbidities. Spawning is protracted and coincides with the rainy season which extends from November to March the following year.  相似文献   

4.
Hand foot and mouth disease is a febrile sickness complex characterized by cutaneous eruption (exanthem) on the palms and soles with simultaneous occurrence of muco-cutanous vesiculo-ulcerative lesions (enanthem) affecting the mouth.The illness is caused by a number of enteroviruses with coxsackievirus A16 and enterovirus 71 as the main causative agents.Human enterovirus 71 (EV71) belongs to the species Human enterovirus A under the genus Enterovirus within the family Picornaviridae.EV71 has been associated with an array of clinical diseases including hand foot and mouth disease (HFMD),aseptic meningitis,encephalitis and poliomyelitis-like acute flaccid paralysis.A large outbreak of HFMD due to highly neurovirulent EV71 emerged in Malaysia in 1997,and caused 41deaths amongst young children.In late 2000,a recurrence of an outbreak of HFMD occurred in Malaysia with S fatalities in peninsular Malaysia.Outbreak of HFMD due to EV71 recurred in 2003 with an unknown number of cases and mortalities.A similar outbreak of HFMD with 2 recorded deaths in young children occurred in peninsular Malaysia in late 2005 and this was followed by a larger outbreak in Sarawak (Malaysian Borneo) with 6 reported fatalities in the early part of 2006.The current on-going outbreak of HFMD started in peninsular Malaysia in epidemiological week 12 of 2010.As with other HFMD outbreaks in Malaysia,both EV71 and CA16 were the main aetiological viruses isolated.In similarity with the HFMD outbreak in 2005,the isolation of CA16 preceded the appearance of EV71.Based on the VP 1 gene nucleotide sequences,4 sub-genogroups of EV71 (C1,C2,B3 and B4) co-circulated and caused the outbreak of hand,foot and mouth disease in peninsular Malaysia in 1997.Two sub-genogroups (C1 and B4) were noted to cause the outbreak in 2000 in both peninsular Malaysia and Sarawak.EV71 of sub-genogroup B5 with smaller contribution from sub-genogroup C1 caused the outbreak in 2003.In the 2005 outbreak,besides the EV71 strains of sub-genogroup C1,EV71 strains belonging to sub-genogroup B5 were isolated but formed a cluster which was distinct from the EV71 strains from the sub-genogroup B5 isolated in 2003.The four EV71 strains isolated from clinical specimens of patients with hand,foot and mouth disease in the Sarawak outbreak in early 2006 also belonged to sub-genogroup B5.Phylogenetic analysis of the VP1 gene suggests that the EV71 strains causing the outbreak in Sarawak could have originated from peninsular Malaysia.Epidemiological and molecular data since 1997 show the recurrence of HFMD due to EV71 in Malaysia every 2 to 4 years.In each of the past outbreaks,more than one sub-genogroup of the virus co-circulate.  相似文献   

5.
In this study, we sequenced a partial segment of the mitochondrial control region from 21 proboscis monkeys of the Klias peninsula, the last large population remaining on the west coast of Sabah, Malaysia. Our results showed that this population retains substantial genetic variation, and subpopulations from different river systems in the central and southern portions of the Klias share multiple haplotypes. We also compared our data with previously generated sequences from 2 eastern populations of proboscis monkeys in Sabah and found little evidence of regional genetic structure. Based on these results, we argue that conservation efforts should focus on restoring connectivity between central and southern Klias peninsula proboscis monkeys and discuss future analyses needed to better understand the mitochondrial structure of proboscis monkeys in Sabah.  相似文献   

6.
The genetic diversity of the endangered crocodile Tomistoma schlegelii was characterized using the protein coding ND 6-tRNAglu-cyt b and the cytochrome b-control region (cyt b-CR) markers. Concatenate data revealed six haplotypes with an overall haplotype diversity of 0.769 ± 0.039; nucleotide diversity was 0.00535 ± 0.00172. A nearest-neighbor analysis showed that all individuals clustered with four geographic regions (Sumatra, Peninsular Malaysia, Sarawak, and East Kalimantan) and were genetically differentiated. With the exception of the individuals from haplotype H2, which occurred in both Peninsular Malaysia and Sarawak, all other haplotypes were geographically distinct. The H4 lineage, which was found to be the most divergent, clustered exclusively in the basal clade in all phylogenetic trees, and the haplotype network was unconnected at the 95% reconnection limit, suggesting further investigation to establish its possible status as a distinct evolutionary significant unit or a cryptic species.  相似文献   

7.
We provide confirmed photographic evidence for the previously overlooked occurrence of the polyphyletic Asian gecko genus Cnemaspis from Gunung Mulu National Park, the world-renowned UNESCO natural heritage site in northern Sarawak, East Malaysia. This new record from Sarawak province represents a remarkable range extension for Cnemaspis cf. kendallii by 550 km to the northeast and denotes the most northern occurrence of the genus in Borneo. Our new finding makes it very likely that these gekkonid lizards also inhabit appropriate limestone karst habitats in adjacent Sabah, Brunei, and Kalimantan. Given the visible differences in the Mulu specimen compared to those from the remaining distribution range on Borneo and the Malaysian Peninsula together with the fact that numerous Cnemaspis species are restricted to small areas, it seems plausible that another undescribed, rather cryptic and possibly locally endemic Bornean species is involved. Lastly, the new record contributes to the importance of the Mulu National Park as a major conservation area in East Malaysia of international concerns.  相似文献   

8.
Etlingera corneri , a new species from peninsular Malaysia and southern Thailand is described and illustrated.  相似文献   

9.
Malaysia remains as a crossroad of different cultures and peoples, and it has long been recognized that studying its population history can provide crucial insight into the prehistory of Southeast Asia as a whole. The earliest inhabitants were the Orang Asli in Peninsular Malaysia and the indigenous groups in Sabah and Sarawak. Although they were the earliest migrants in this region, these tribes are divided geographically by the South China Sea. We analyzed DNA sequences of 18 Orang Asli using mitochondrial DNA extracted from blood samples, each representing one sub-tribe, and from five Sarawakian Iban. Mitochondrial DNA was extracted from hair samples in order to examine relationships with the main ethnic groups in Malaysia. The D-loop region and cytochrome b genes were used as the candidate loci. Phylogenetic relationships were investigated using maximum parsimony and neighbor joining algorithms, and each tree was subjected to bootstrap analysis with 1000 replicates. Analyses of the HVS I region showed that the Iban are not a distinct group from the Orang Asli; they form a sub-clade within the Orang Asli. Based on the cytochrome b gene, the Iban clustered with the Orang Asli in the same clade. We found evidence for considerable gene flow between Orang Asli and Iban. We concluded that the Orang Asli, Iban and the main ethnic groups of Malaysia are probably derived from a common ancestor. This is in agreement with a single-route migration theory, but it does not dismiss a two-route migration theory.  相似文献   

10.
大鳞裂峡鲃繁殖生物学特征   总被引:3,自引:2,他引:1  
2009、2010和2013年在云南省西双版纳自治州勐腊县境内的南腊河共收集大鳞裂峡鲃(Hampala macrolepidota)样本438尾。研究结果表明:大鳞裂峡鲃雌性群体初次性成熟体长228 mm、体重270.3 g,雄性群体初次性成熟体长205 mm、体重172.5 g,对应年龄均为4龄。大鳞裂峡鲃雌、雄繁殖群体的成熟系数年度变化趋势基本一致。成熟系数值在1月、3月、4月呈逐渐增大趋势,5月显著上升,6月达到最高峰,7月急速下降,8月至9月趋于平缓。繁殖活动每年4月开始,一直可持续至10月,主要集中在5~6月。大鳞裂峡鲃雌雄性比为1︰1.19,与鲃亚科其他部分鱼类雌性数量多于雄性的情况相反;繁殖盛期则雌性数量多于雄性。繁殖群体由4~8龄共5个年龄组组成,雌、雄群体均以5龄组所占比例最大。大鳞裂峡鲃属单次产卵鱼类。平均卵径1.18 mm;绝对繁殖力为63 393粒,相对繁殖力为70.04粒/g。与鲃亚科其他部分鱼类比较,大鳞裂峡鲃的卵径相对较小而繁殖力较大。  相似文献   

11.
The genus Meristogenys (Anura: Ranidae), endemic to Borneo, presents serious taxonomic problems despite being one of the commonest frogs in the mountainous regions of this island. We investigated molecular and morphological variations in Meristogenys whiteheadi (Boulenger, 1887) using larval and adult specimens from Sabah and Sarawak (Malaysia). We found three allopatric lineages in this species. We regard each of these as a distinct species because they are separated by a large genetic distance, and do not form any monophyletic group. Their morphological characters indicate that the distributional range of M. whiteheadi s.s. is divided into two disjunct areas: Mt Kinabalu (northern Sabah) and northern Sarawak. The two other lineages occupy ranges between those of M. whiteheadi, and represent undescribed cryptic species. One of these, Meristogenys stigmachilus sp. nov. , collected from the northern part of the Crocker Range, is distinguished from M. whiteheadi by black spots on the upper lip and dark dots scattered on the back. A second undescribed species, Meristogenys stenocephalus sp. nov. , was collected mainly from the southern part of the Crocker Range, and is characterized by the large body size of males and a relatively narrow head. Meristogenys stenocephalus sp. nov. also differs from M. stigmachilus sp. nov. and M. whiteheadi in larval morphology, but larvae of the latter two cannot be differentiated morphologically. We discuss relative tibia length, a diagnostic specific characteristic in the genus Meristogenys, and the relationships between body size and sexual size dimorphism in this genus. © 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2011, 161 , 157–183.  相似文献   

12.
Invasive species are one of the main sources of the ongoing global loss of biodiversity. Invasive ants are known as particularly damaging invaders and their introductions are often accompanied by population-level behavioural and genetic changes that may contribute to their success. Anoplolepis gracilipes is an invasive ant that has just recently received increased attention due to its negative impact on native ecosystems. We examined the behaviour and population structure of A. gracilipes in Sabah, Malaysia. A total of 475 individuals from 24 colonies were genotyped with eight microsatellite markers. Intracolonial relatedness was high, ranging from 0.37 to 1 (mean +/- SD: 0.82 +/- 0.04), while intercolonial relatedness was low (0.0 +/- 0.02, range -0.5-0.76). We compared five distinct sampling regions in Sabah and Brunei. A three-level hierarchical F-analysis revealed high genetic differentiation among colonies within the same region, but low genetic differentiation within colonies or across regions. Overall levels of heterozygosity were unusually high (mean H(O) = 0.95, mean H(E) = 0.71) with two loci being entirely heterozygous, indicating an unusual reproductive system in this species. Bioassays revealed a negative correlation between relatedness and aggression, suggesting kinship as one factor facilitating supercolony formation in this species. Furthermore, we genotyped one individual per nest from Sabah (22 nests), Sarawak (one nest), Brunei (three nests) and the Philippines (two nests) using two mitochondrial DNA markers. We found six haplotypes, two of which included 82.1% of all sequences. Our study shows that the sampled area in Sabah consists of a mosaic of differently interrelated nests in different stages of colony establishment. While some of the sampled colonies may belong to large supercolonies, others are more likely to represent recently introduced or dispersed propagules that are just beginning to expand.  相似文献   

13.
We postulated that the biogeographical history of South-east Asia contributed to extensive admixture during Pleistocene low sea levels of genetic groups of an obligate freshwater fish (the river catfish, Hemibagrus nemurus) isolated during periods of high sea levels. During Pleistocene glacial maxima, the sea level was lower than at present and the islands of the Sunda shelf (Sumatra, Borneo and Java) and the Asian mainland were connected by lowlands traversed by rivers. Restriction fragment length polymorphisms in mitochondrial DNA were documented for 140 putative H. nemurus analysed from 13 sampling sites resulting in the definition of 35 haplotypes. The high level of haplotype differentiation (mean P × 100 = 2.22, SD = 1.33) indicates that the subdivision of the ancestral H. netnurus group was extensive and probably occurred early in the Pleistocene. The occurrence of some genetically divergent groups of the H. netnurus complex occurring in sympatry in widely separated locations supports the proposition that low sea levels aided the dispersion and mingling of genetic groups. Based on both genetic and morphological evidence, the main H. nemurus line gave rise to three regional groups: (1) a morphologically distinct ‘Indochinese’ group composed of two mtDNA clades overlapping in east peninsular Malaysia; (2) a ‘Sundaic’ group composed of various lineages of differing morphology and genetic identity; (3) a genetically distinct ‘Sarawak’ group in west Borneo, similar in morphology to the ‘Sundaic’ and ‘Indochinese’ groups, but including a small, golden colour morph as a distinct dade. The morphologically similar Sundaic forms from west Java, Sumatra and west Borneo show some degree of genetic divergence, but their phylogenetic relationships are poorly resolved. The most genetically and morphologically distinct Sundaic dade, assigned to H. hoevenii, colonized the Kapuas river (west Borneo), east Sumatra and south peninsular Malaysia. Contrary to our original hypothesis and present biogeographical theory, little exchange of genetic groups has apparently occurred between the mainland and the Sunda Islands during recent glaciations.  相似文献   

14.
A new record of the rhacophorid frog, Theloderma licin is reported from Gunung Serambu, in the Bau region of western Sarawak, East Malaysia, which comprises the first published record of the species from the Sundaic island of Borneo. The species was previously known from the Malay Peninsula (southern Peninsular Thailand and Peninsular Malaysia). Species of Theloderma are widespread in mainland and insular Southeast Asia, their arboreal habits perhaps contributing to our perception of rarity.  相似文献   

15.
Three new species from northern Borneo are described: Etlingera rubromarginata from Sarawak, Brunei and Sabah; E. belalongensis presently only known from the Temburong District of Brunei; and E. corrugata presently only known from Danum Valley, Sabah.  相似文献   

16.
Sera from 420 military personnel serving in Sabah and Sarawk, Malaysia, were tested for antibodies to Pseudomonas pseudomallei exotoxin and whole cell antigens by enzyme-linked immunosorbent assay procedure (ELISA). Data showed that 54.4% of serum samples were positive for antibodies to P. pseudomallei exotoxin and 65.7% were positive for antibodies to the whole cell antigens. Samples gave much lower titers for anti-exotoxin antibodies compared to titers against crude whole cell antigens. The incidence of antibody to exotoxin was highest in the age groups ranging from 26 to 32 years, where the positive rates were higher than 40% and 30% for military personnel serving in Sarawak and Sabah, respectively.  相似文献   

17.
The genus Menegazzia (Parmeliaceae, lichenized ascomycetes) in Malaysia and Indonesia is studied. Some specimens from Papua New Guinea are also included. The great majority of available specimens are from Kinabalu Park, State of Sabah, Malaysia. Three species are described as new to science, namely the two sorediate species M. capitata (from Sabah and Pahang in Malaysia) and M. sabahensis (from Sabah), and the fertile, primary species M. monospora (from Sabah and Papua New Guinea). M. asahinae , M. dissoluta , and M. efflorescens are reported for the first time from Malaysia, and M. subsimilis is reported for the first time from Malaysia and Indonesia. The subgenus Megamenegazzia is newly described to accommodate the large, broad-lobed species with numerous perforations on the lower surface. M. efflorescens is selected as the type species for the new subgenus. Notes are also provided on the type specimens of Hypogymnia pectinatula , a species originally considered as belonging to Menegazzia .  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 153 , 489–499.  相似文献   

18.
Summary Malays, Chinese and Indians from peninsular Malaysia; Ibans and Bidayuh from Sarawak state, Northern Borneo; and Bataks, Minangkabau and Javanese from North Sumatra, Indonesia, were subtyped for Gc (group-specific component) by polyacrylamide gel isoelectric focusing. All eight populations investigated were found to be polymorphic for three common alleles, GcIF, GcIS and Gc2.  相似文献   

19.
20.
Matsui M  Yambun P  Sudin A 《Zoological science》2007,24(11):1159-1166
Examination of types and recently collected specimens revealed that Ansonia anotis Inger, Tan, and Yambun, 2001 and Pedostibes maculatus (Mocquard, 1890), both described from Kinabalu, Sabah, Malaysia, are hardly differentiated morphologically. Analyses of a total of 2,427 bp of the 12S rRNA, tRNA(val), and 16S mitochondrial rRNA genes revealed that the two species are very close genetically. Thus A. anotis is regarded as conspecific and is synonymized with P. maculatus. Genetically, this species proved to form a lineage distinct from other bufonids from Southeast Asia, including species of Ansonia and Pedostibes. Because the species has also some unique morphological traits different from known bufonid genera, we propose to establish a new genus for Nectophryne maculata Mocquard, 1890.  相似文献   

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