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A group of seven Polyalthia species from Borneo allied to P. cauliflora Hook. f. & Thomson is revised. Three of these are described as new. Polyalthia myristica sp. nov. and P. trochilia sp. nov. are similar to P. stenopetala (Hook. f. & Thomson) Finet & Gagnep., particularly in having seeds with a deep circumferential groove. Polyalthia kinabaluensis sp. nov., endemic to Mount Kinabalu, is similar to P. cauliflora, but differs in having petals slightly connate at the base and larger monocarps. Polyalthia ichthyosma sp. nov. is the fourth new species described. It bears some similarity to one of the P. cauliflora group, P. dictyoneura Diels, but differs in not being cauliflorous. Two synonyms of Polyalthia cauliflora, Unona desmantha Hook. f. & Thomson and Unona pycnantha Hook. f. & Thomson, are lectotypified.  相似文献   

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暗罗属植物叶的比较解剖学研究   总被引:6,自引:0,他引:6  
利用扫描电镜技术、叶片叶片离析方法和石蜡切片法对暗罗属12种植物叶和形态结构进行了比较研究。结果表明,叶表皮细胞形状、气孔器形态、表皮毛类型、表皮细胞中晶体类型、叶肉中油细胞分布位置、栅栏组织和海绵组织厚度的比值,以及主脉维管组织的结构特征等具有明显的种间差异。可以利用这些叶的解剖特征将暗罗属植物相互区别开来。  相似文献   

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The species of Goniothalamus (Annonaceae) occurring in Peninsular Malaysia and Singapore are revised, updating the previous taxonomic treatment by James Sinclair, published in 1955. A total of 18 species is recognized, including a new species, G. tomentosus . Collections referrable to G. tomentosus were previously determined as ' G. marcanii '; examination of the types of G. marcanii reveals that the two taxa are not conspecific, however, and a new name is accordingly validated here. Goniothalamus tomentosus has closest affinities with the Javan/Sumatran species G. costulatus . Other important nomenclatural changes include the reduction of G. umbrosus to synonymy with G. tapis .  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society, 2003, 142 , 321−339.  相似文献   

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Polyalthia yingjiangensis sp. nov. is described from the China/Myanmar border. It is distinct in having outer petals that are much shorter than the inner petals and having a very long pedicel. It is most similar to P. miliusoides I.M. Turner, but differs in having perianth parts that are glabrous adaxially and pubescent abaxially, thicker and sparsely pubescent pedicels, as well as verrucose and darker monocarps.  相似文献   

6.
Damselfishes (Pomacentridae) are among the most common of reef fishes in tropical seas, comprising 320 species in all, with 268 species alone in the Indo-West Pacific regions. 15 genera (Abudefduf, Amblyglyphidodon, Amphiprion, Chelioprion, Chromis, Chrysiptera, Dascyllus, Pristotis, Dischistodus, Hemiglyphidodon, Neoglyphidodon, Neopomacentrus, Plectroglyphidodon, Pomacentrus, Stegastes) and at least 39 species inhabit the waters of Peninsular Malaysia and Singapore. They are important ecologically because many species are extremely abundant in reefs, and also economically, as several are collected in large numbers for the lucrative aquarium trade. This demand has led to some fishermen using destructive methods in obtaining the fishes, to the point that original standing populations may not be recoverable. This threat poses a need for conservation of the reefs. The present study based primarily on fishes collected from the waters of Singapore and specimens from the Zoological Reference Collection at the National University of Singapore, will serve the dual purpose of establishing a current species list for Malaysia and Singapore, and to update and clarify the local taxonomy of the group. An annotated list (with localities) is provided of the known or reported species to aid studies on reefs.  相似文献   

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Ni X  Huang Y  Wu L  Zhou R  Deng S  Wu D  Wang B  Su G  Tang T  Shi S 《Genetica》2006,127(1-3):177-183
Primulina tabacum Hance, is a critically endangered perennial endemic to limestone area in South China. Genetic variability within and among four extant populations of this species was assessed using AFLP markers. We expected a low genetic diversity level of this narrowly distributed species, but our results revealed that a high level of genetic diversity remains, both at population level (55.5% of markers polymorphic, H E = 0.220, I S = 0.321), and at species level (P = 85.6% of markers polymorphic, H E = 0.339, I S = 0.495), probably resulting from its refugial history and/or breeding system. High levels of genetic differentiation among populations was apparent based on Nei’s genetic diversity analysis (G st=0.350). The restricted gene flow between populations is a potential reason for the high genetic differentiation. The population genetic diversity of P. tabacum revealed here has clear implications for conservation and management. To maintain present levels of genetic diversity, in situ conservation of all populations is necessary.  相似文献   

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A new species of Annonaceae, Mitrephora sirikitiae , is described from Mae Hong Son Province in northern Thailand. It is easily distinguished from the seven species of Mitrephora previously recorded from Thailand due to its very large, showy flowers. It is most similar to M. winitii , but differs in its larger flowers, with inner petals that become undulate at maturity. The profuse blooming of the new species and its large flowers with mild fragrance suggest that may be of significant horticultural potential.  相似文献   

9.
A revised classification of the species of Cyathocalyx (Annonaceae) occurring in western Malesia (Peninsular Malaysia, Sumatra, and Borneo) is presented, with distribution maps. Fifteen species are recognized, including two that are newly described from Borneo ( C. angustipetalus and C. magnifructus ), which are illustrated. Several important nomenclatural changes are validated, including the elevation of Drepananthus carinatus var. deltoideus to specific rank as C. deltoideus , and the transfer of the name Parartabotrys hexagynus to Cyathocalyx as C. hexagynus . Other notable nomenclatural changes include the reduction of the name C. scortechinii to synonymy with C. pubescens .  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 152 , 513–532.  相似文献   

10.
The species-rich genus Polyalthia has previously been shown to be highly polyphyletic, with species represented in at least five different clades. The Polyalthia species that are associated with Marsypopetalum and Trivalvaria (as revealed either by previous phylogenetic studies or inferred on the basis of comparative morphology) were included in a molecular phylogenetic study based on three chloroplast DNA regions (matK, rbcL and trnL-F). Maximum parsimony, maximum likelihood and Bayesian analyses consistently revealed that several Polyalthia species form a well-supported clade with Marsypopetalum pallidum, and that this clade is sister to Trivalvaria. Diagnostic morphological characters for the clades are re-evaluated and shown to be congruent with the molecular phylogeny. Five Polyalthia species (P. crassa, P. littoralis, P. lucida, P. modesta and P. tristis) are accordingly transferred to Marsypopetalum.  相似文献   

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In continuation of our study on medicinal plants of Cameroon, stem barks of Polyalthia suaveolens were phytochemically studied. This investigation yielded a new indolosesquiterpene alkaloid, named polysin (1) and four hitherto known alkaloids (2–5). Polysin (1) appeared as a competitive reversible inhibitor (Ki = 10 μM) of phosphofructo kinase (PFK) of Trypanosoma brucei with respect to fructose-6-phosphate (Ki/KM = 0.05) and could be used in the design of new trypanocidal drugs. The other isolated compounds (2–5) also exhibited interesting inhibitory effects on selected glycolytic enzymes (PFK, glyceraldehyde-3-phosphate dehydrogenase and aldolase).  相似文献   

13.
Three new species of Mitrephora (Blume) Hook. f. & Thomson, M. clemensiorum, M. vittata and M. woodii , are described from Sabah, Malaysia. Mitrephora clemensiorum is related to M. korthalsiana Miq., but is distinguished by having long inflorescences, long flowering and fruiting pedicels, and fruits with sessile monocarps. Mitrephora vittata is related to M. reflexa Merr., but has lanceolate, subcoriaceous leaves, and densely pubescent inflorescence rachides, flowering pedicels and bracts. Mitrephora woodii is similar to M. heyneana (Hook. f. & Thomson) Thwaites, but has smaller flowers and fruits with sessile monocarps  相似文献   

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《Journal of Asia》2014,17(3):333-338
Graphium butterflies are famous in Peninsular Malaysia for their colourful wings, yet their taxonomy remains unresolved. The popular guides to Malaysian butterflies, place the species in one, two or three genera and identification to species using obscure morphological characters can be difficult, especially for the closely related species, G. bathycles bathycloides and G. chironides malayanum. We sequenced the COI mtDNA barcode for Graphium specimens in the Museum of Zoology, University of Malaya to test the utility of DNA barcoding for the identification of Graphium species. Additionally, we sequenced 28S rRNA to examine, in conjunction with COI, the phylogenetic relationships of these species and investigate the validity of Pathysa and Paranticopsis as distinct genera. We found that all species of Graphium possessed a distinctive cluster of DNA barcodes with the exception of specimens originally identified as G. bathycles bathycloides and G. chironides malayanum which shared DNA barcodes. On further examination we found that the morphological determinations were ambiguous as the specimens overlapped for diagnostic characters reported for each species. The COI and 28S rRNA phylogenetic trees showed a similar topology with Paranticopsis species forming a clade nested within a larger clade also comprising Pathysa species. Based on this topology, in order for Pathysa to be a valid genus, at least three other clades within Graphium s.l. would also have to be raised as genera.  相似文献   

17.
Two new and two previously described species of diplectanid monogeneans (Heteroplectanum flabelliforme n. sp., Diplectanum sumpit n. sp., D. jaculator Mizelle & Kritsky, 1969 and D. toxotes Mizelle & Kritsky, 1969) were collected from archerfish Toxotes jaculatrix off the Island of Langkawi, Kedah and off Perak, Malaysia. The reproductive systems and squamodiscs of D. jaculator and D. toxotes are described for the first time. D. sumpit n. sp. differs from D. toxotes and D. jaculator in a having a small curved copulatory tube with a distinct accessory piece, compared to the long, tubular copulatory tube of D. jaculator and the slender tube of D. toxotes. D. sumpit n. sp. also differs from D. toxotes in having a larger ventral bar and larger squamodiscs. H. flabelliforme n. sp. differs from all known Heteroplectanum species in the shape and size of the squamodiscs, the arrangement of the sclerites in the squamodiscs, the extremely large ventral bar and the short, curved, non-spinous copulatory tube.  相似文献   

18.
All four nightjar species resident in Peninsular Malaysia are vocally distinct, yet they remain little studied. Conventional field methods based on visual cues to study diurnal species may be impractical for nightjars. Alternatively, aural survey can potentially be applied on nightjars provided that individuality in their vocalisations can be proven. Our study aimed to determine the vocal individuality of the common, large-tailed nightjar (Caprimulgus macrurus) in oil palm smallholdings and an isolated forest patch located in Selangor, Peninsular Malaysia. From the call recordings obtained from 22 individuals, results of the Kruskal-Wallis analysis revealed significant differences in all the nine vocal parameters (call length, interquartile range bandwidth, low, high, average, centre and peak frequencies as well as first and third quartile frequencies) measured among individual nightjars (p < 0.001) regardless of study sites. Discriminant Function Analysis showed that more than 94.5% of original grouped cases were correctly classified. This implied that the majority of vocalizations can be assigned to individual birds based on the parameters measured. This study demonstrated the occurrence of vocal individuality in the large-tailed nightjar and such a finding pertaining to distinct vocalisations at the individual level will compensate for the limited access to visual cues in field surveys, as with the case for all nocturnal birds.  相似文献   

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Fungal infection in sea turtle nests has become a potential threat to sea turtle embryos. We screened the hatchery nest sand, eggshells of failed eggs, and stillbirths of green turtles and hawksbills collected from hatcheries in Malacca, Pahang, Perak and Terengganu for the presence of fungi. The DNA sequence of the ITS region of the three highest occurring isolated fungi confirmed that these species were Pseudallescheria ellipsoidea (35.4%), Scedosporium aurantiacum (27.2%), and Fusarium solani (22.0%). Morphological characteristics of these fungi were recorded. Although the total fungi abundance had no significant effect on hatching success (p > 0.05), the abundance of P. ellipsoidea significantly increased mortality in the nests (r = 0.70, p < 0.05). Future research should focus on understanding the biological aspects of this species to establish a more effective mitigation technique for the prevention of fungal infection of sea turtle eggs and hatchery employees.  相似文献   

20.
1. Population samples of Bactrocera albistrigata from Peninsular Malaysia were analyzed for 12 to 14 gene-enzyme systems comprising 15-18 loci. 2. Three loci, aMDH, PGD and PGM, were polymorphic. 3. Anodal malate dehydrogenase and phosphogluconate dehydrogenase were represented by two alleles each, while phosphoglucomutase was represented by three alleles. 4. Phosphoglucomutase had a higher heterozygosity than anodal malate dehydrogenase and phosphogluconate dehydrogenase. 5. B. albistrigata was characterized by low genetic variability, as measured by the proportion of polymorphic loci and heterozygosity.  相似文献   

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