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1.
Summary  A taxonomic revision of the palm genus Podococcus (Arecaceae) is presented. Two species are recognised: P. barteri, a species relatively widespread in a coastal band from Nigeria to the D. R. Congo and P. acaulis, a species previously considered conspecific to P. barteri, almost exclusively confined to Gabon. The taxonomic history, morphology, distribution and conservation status of the genus and each species are discussed  相似文献   

2.
The first species of the small Afrotropical family Ammodesmidae discovered in central Africa (Democratic Republic of the Congo) belongs to the genus Ammodesmus Cook, 1896, which was hitherto known only from two species in western Africa. A key is given to incorporate Ammodesmus congoensis sp. n., a species also showing an evident sex dimorphism: ♂ densely hirsute, ♀ with much longer and sparser tergal setae.  相似文献   

3.
陈法军 《菌物学报》1992,11(Z1):23-64
被孢霉属(Mortierella Coemans)是接合菌纲(Zygomycetes)、毛霉目(Mucorales)、被孢霉科(Mortierellaceae)中的一个大属,目前已知约有90种;主要存在于土壤、植物残体、动物粪便等基物中。我国过去对被孢霉的研究不多,在《中国真菌总汇》(1979)中记录了8个种。本研究从全国22个省、市、自治区采集的2000多号样品中,分离到约220个被孢霉菌株。本研究主要采用Gams (1970, 1977)的分类系统进行分类鉴定,并对该系统进行了修改。在属下分3个亚属(Micromucor, MortierellaGamsiella), 8个组(Actinomortierella, Alpina,Hygrophila, Mortierella, Schmuckii, Simplex, SpinosaStylospora),单囊霉(Haplosporangium)被承认为独立的一个属。本研究鉴定出22个种和3个变种,包括一个新种(武夷山被孢霉Mortierella wuyishanensis sp. nov.)和一个新变种(极细无色被孢霉Mortierella hyalina(Harz) W. Gams var. subtilissima var. nov.), 14个中国新纪录。这14个新纪录为:产芽胞被孢霉(Mortierella. gemmifera M. Ellis)、园圃被孢霉(M. horticola Linnem.)、矮小被孢霉(M. humilis Linnem.)、无色被孢霉(M. hyalina(Harz) W. Gams)、印度被孢霉(M. indica B.S. Mehrotra)、英杜被孢霉(M. indohii C.Y. Chien),詹金氏被孢霉(M. jenkinii (A.L. Sm.) Naumov)、可疑极小被孢霉(M. minutissima Tiegh. var. dubia Linnem.)、易变被孢霉(M. mutabilis Linnem.)、微孢被孢霉(M. parvispora Linnem.)、角胞拉曼被孢霉(M. ramanniana(Moller) Linnem. var. angulispora (Naumov) Linnem.)、网孢被孢霉(M. reticulata Tiegh.& G. Le Monn.)、多疣被孢霉(M. verrucosa Linnem.)、轮枝被孢霉(M. verticillata Linnem.)。文中讨论和评价了一些分类性状,还列出分亚属、分组、分种和变种的检索表.每个分类单元都有描述和讨论以及线条图、并列出分布地区。  相似文献   

4.
Partial gyrB sequences (>1 kb) were obtained from 34 type strains of the genus Amycolatopsis. Phylogenetic trees were constructed to determine the effectiveness of using this gene to predict taxonomic relationships within the genus. The use of gyrB sequence analysis as an alternative to DNA–DNA hybridization was also assessed for distinguishing closely related species. The gyrB based phylogeny mostly confirmed the conventional 16S rRNA gene-based phylogeny and thus provides additional support for certain of these 16S rRNA gene-based phylogenetic groupings. Although pairwise gyrB sequence similarity cannot be used to predict the DNA relatedness between type strains, the gyrB genetic distance can be used as a means to assess quickly whether an isolate is likely to represent a new species in the genus Amycolatopsis. In particular a genetic distance of >0.02 between two Amycolatopsis strains (based on a 315 bp variable region of the gyrB gene) is proposed to provide a good indication that they belong to different species (and that polyphasic taxonomic characterization of the unknown strain is worth undertaking). Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. The GenBank accession numbers for the gyrB gene sequences obtained in this study are shown in Table 1.  相似文献   

5.
梭菌属分类研究进展:现状和展望   总被引:2,自引:0,他引:2  
目前构成梭菌属的微生物在系统发育和表型特征上不一致。多相分类数据表明,梭菌属物种之间差异大。大量基于16S rRNA 基因的系统发育研究表明,梭菌属应被限定为梭菌属类群I,作为狭义梭菌属(Clostridium sensu stricto)。尽管有这方面认识,梭菌属新物种仍持续增加,这些新物种并不能与梭菌属类群I 和标准种丁酸梭菌(C. butryicum)形成一致分支,引发梭菌属分类上的混乱。本文明确了梭菌属物种的范围,即只包括模式种和梭菌属类群I。此外,4 个物种念珠状真杆菌(Eubacterium moniliforme)、旋舞真杆菌(Eubacterium tarantellae)、最大八叠球菌(Sarcina maxima)和胃八叠球菌(Sarcina ventriculi)应被调至梭菌属,分别命名为念珠状梭菌(Clostridium moniliforme)、旋舞梭菌(Clostridium tarantellae)、最大梭菌(Clostridium maximum)和胃梭菌(Clostridium ventriculi)。一个新属哈撒韦氏菌属(Hathewaya)被提议成立,3 个梭菌属物种溶组织梭菌(Clostridium histolyticum)、泥渣梭菌(Clostridium limosum)和解朊梭菌(Clostridiumproteolyticum)重新归为溶组织哈撒韦氏菌(Hathewaya histolytica)、泥渣哈撒韦氏菌(Hathewaya limosa)和解朊哈撒韦氏菌(Hathewaya proteolytica),其中Hathewaya histolytica 为模式种。  相似文献   

6.
Martin Fikáček 《Biologia》2006,61(2):149-157
Pachysternum loxodonta sp. n. from the Republic of the Congo and Pachysternum sulawesicum sp.n. from Sulawesi Island, Indonesia are described. The generic status of Pachysternum sculpticolle (Régimbart, 1907) is revised, the species is transferred to the genus Cyrtonion and its differences from C. ghanense Hansen, 1989 are discussed. Taxonomy of Pachysternum is discussed, dividing the genus prelusively into three species groups, one comprising all known Oriental and Eastern Palearctic species, and two comprising the Afrotropical species. Species with unclear positions within the genus Pachysternum or with questionable generic status are left as “Species incertae sedis”.  相似文献   

7.
On the basis of craniometry, the last systematic revision of cusimanses recognized four species distributed from Guinea (Conakry) to the eastern Democratic Republic of the Congo (DRC). Here, we (re)investigated cusimanses including new specimens collected in Benin, in eastern Cameroon (near the Dja River) and in Central African Republic (CAR) where cusimanses were so far presumed to be absent or had been barely sampled. Using craniometry and two mitochondrial DNA fragments (16S rDNA and cytochrome b), we were able to classify most investigated specimens according to the current taxonomy (viz. Crossarchus obscurus, C. platycephalus, C. alexandri and C. ansorgei). Interestingly, all the specimens from CAR clustered unambiguously with Crossarchus alexandri in the DNA‐based analyses but exhibited skull dimensions that were distinct from the four recognized species. Our craniometric and mitochondrial DNA analyses offered two valuable complementary viewpoints to characterize cusimanses but were insufficient to provide a firm taxonomic conclusion about the specimens from CAR. Phylogenetic analyses based on mitochondrial DNA suggested that the two sympatric species living on the left bank of the Congo River were sister‐species.  相似文献   

8.
A specimen of the African weakly electric fish genus Petrocephalus (Osteoglossomorpha, Mormyridae) collected in the Congo River at Yangambi, Orientale Province, Democratic Republic of Congo, is described as a new species. Petrocephalus boboto sp. n. can be distinguished from other Central African species of Petrocephalus by a combination of the following characteristics: three distinct black spots on the body, one at the origin of the pectoral fin, one at the origin of the caudal fin and one below the anterior base of the dorsal fin; Nakenrosette and Khelrosette electroreceptor clusters distinct on head but Augenrosette cluster reduced in size; 23 branched dorsal rays, 34 branched anal rays, and electric organ discharge waveform triphasic. Petrocephalus boboto sp. n. most closely resembles the holotype of Petrocephalus binotatus but is easily distinguished from it by its smaller mouth. A comparative molecular analysis including 21 other Petrocephalus species shows Petrocephalus boboto sp. n. to be genetically distinctive and to represent a deep lineage in the genus. Two specimens of Petrocephalus collected at Yangambi are morphologically similar and genetically closely related to specimens previously assigned to Petrocephalus binotatus, collected in the northwestern Congo River basin within Odzala-Kokua National Park, Republic of the Congo. This prompts us to formally describe a new species from these collections, Petrocephalus arnegardi sp. n., that, although similar to the holotype of Petrocephalus binotatus, can be distinguished from it by its smaller mouth and shorter interorbital width.  相似文献   

9.
10.
Two new species of Polystachya Hook. are described and illustrated: Polystachya rydingii Baranow & Mytnik occurring from the Democratic Republic of Congo and P. sosefii Baranow & Mytnik from Cameroon. The species belong to the section Polystachya Kraenzl., which is the only pantropical section in the genus. Maps of the distribution for the new species and their closest relatives and a brief discussion with notes on their habitat, ecology, and altitude are provided.  相似文献   

11.
Scirtothrips perseae Nakahara was discovered attacking avocados in California, USA, in 1996. Host plant surveys in California indicated that S. perseae has a highly restricted host range with larvae being found only on avocados, while adults were collected from 11 different plant species. As part of a management program for this pest, a “classical” biological control program was initiated and foreign exploration was conducted to delineate the home range of S. perseae, to survey for associated natural enemies and inventory other species of phytophagous thrips on avocados grown in Mexico, Guatemala, Costa Rica, the Dominican Republic, Trinidad, and Brazil. Foreign exploration efforts indicate that S. perseae occurs on avocados grown at high altitudes (>1500 m) from Uruapan in Mexico south to areas around Guatemala City in Guatemala. In Costa Rica, S. perseae is replaced by an undescribed congener as the dominant phytophagous thrips on avocados grown at high altitudes (>1300 m). No species of Scirtothrips were found on avocados in the Dominican Republic, Trinidad, or Brazil. In total, 2136 phytophagous thrips were collected and identified, representing over 47 identified species from at least 19 genera. The significance of these species records is discussed. Of collected material 4% were potential thrips biological control agents. Natural enemies were dominated by six genera of predatory thrips (Aeolothrips, Aleurodothrips, Franklinothrips, Leptothrips, Scolothrips, and Karnyothrips). One genus each of parasitoid (Ceranisus) and predatory mite (Balaustium) were found. Based on the results of our sampling techniques, prospects for the importation of thrips natural enemies for use in a “classical” biological control program in California against S. perseae are not promising.  相似文献   

12.
Thaumatovalva gen. n. is described and illustrated from the Afrotropical region. As currently defined the genus includes four species: T. deprinsorum sp. n. from the Democratic Republic of Congo; T. albolineana sp. n. (type species) from the Democratic Republic of Congo; T. spinai (Razowski & Trematerra), comb. n., from Ethiopia and Nigeria; and T. limbata (Diakonoff), comb. n., from the Seychelles and Kenya. Thaumatovalva limbata has been reared from the fruit of Cordia somaliensis Baker and C. monoica Roxb. (Boraginaceae) in Kenya. Although structures of the male and female genitalia are extremely similar among three of the four species, male secondary scales on the under surface of the hindwing easily distinguish them.  相似文献   

13.
Chassalia magnificens, a new species from the Albertine Rift in eastern Democratic Republic of Congo, is described and illustrated. The species is recognised inter alia by its large stipules and montane habitat. Chassalia chrysoclada is a new combination for a widespread, but hitherto overlooked, central African species originally described in the genus Psychotria. Chassalia chrysoclada is related to C. pteropetala (K. Schum.) Cheek but lacks the bicostate twigs and dorsally winged corolla lobes of that species.  相似文献   

14.
基于对标本和文献的比较研究,确认豆科香槐属(Cladrastis Raf.)中小叶香槐(C.parvifolia C.Y.Ma)、藤香槐(C.scandens C.Y.Ma)、秦氏香槐(C.chingii DuleyVincent)与本属分布最广的翅荚香槐[C.platycarpa(Maxim.)Makino]为同种植物。其中,小叶香槐被处理为翅荚香槐的一变种,即C.platycarpa var.parvifolia(C.Y.Ma)Z.Q.Song,D.X.XuS.J.Li,藤香槐与秦氏香槐被处理为翅荚香槐原变种的两个新异名。同时讨论了翅荚香槐的分类地位及其散布。  相似文献   

15.
Our study combined a mitochondrial cytochrome b phylogeny with cranial measurements from giant pouched rats collected across sub‐Saharan Africa. The mitochondrial phylogeny resolves two West African clades and a clade with east and central Africa representatives. This last clade can be further divided into four subclades. Altogether they represent six species (Cricetomys gambianus, Cricetomys ansorgei, Cricetomys emini, and three undescribed taxa) that can be distinguished on the basis of their mitochondrial DNA sequences and craniometry. In the absence of adequate craniometric data the existence of Cricetomys kivuensis cannot be confirmed by our data. Our combined molecular and craniometric data allowed us to broadly delineate the distribution ranges of the detected species. Cricetomys gambianus occurs in the savannah and forest clearings of West Africa. Cricetomys ansorgei is distributed in the savannah of East and southern Africa. Cricetomys emini, as currently recognized across the Guineo‐Congolian forest of Africa, is shown to be diphyletic. Cricetomys sp. 1, a separate operational taxonomic unit closely resembling C. emini, occurs in the forest zone of West Africa. An undescribed sister‐species of C. ansorgei, Cricetomys sp. 2, occurs in the forest of Central Africa along the left bank of the Congo River. Cricetomys sp. 3 occurs on the right bank of the Congo River from Cameroon to the Republic of Congo, whereas the true C. emini also occurs on the right bank of the Congo River but appears to be restricted to the Democratic Republic of Congo. Cranial phenotype within the genus tends to conform to ecological zonation (either forest or savannah) rather than to phylogenetic affiliation of the species concerned, suggesting that diversifying selection across environmental gradients could be responsible for biological diversification within the genus.  相似文献   

16.
17.
Summary  Three closely affiliated species of Heterospathe Scheff. (H. elegans (Becc.) Becc., H. humilis Becc. and H. versteegiana Becc.) from New Guinea are revised. They are reduced to a single species which is divided into two subspecies, and the new combination H. elegans subsp. humilis (Becc.) M. S. Trudgen & W. J. Baker is made. The subspecies can be readily distinguished by their growth habit. Epitypes are designated for the three previously published names, as informative material on the habit is not included in the existing type specimens. A new, potentially related species is described as H. pullenii M. S. Trudgen & W. J. Baker.  相似文献   

18.
Ivanova  E. P.  Mikhailov  V. V. 《Microbiology》2001,70(1):10-17
The taxonomic positions of the marine genera Alteromonas, Pseudoalteromonas, Idiomarina, and Colwellia within the gamma subclass of the class Proteobacteria were specified on the basis of their phenotypic, genotypic, and phylogenetic characteristics. Gram-negative aerobic bacteria of the genera Alteromonas, Pseudoalteromonas, and Idiomarina and facultatively anaerobic bacteria of the genus Colwellia were found to form a phylogenetic cluster with a 16S rRNA sequence homology of 90% or higher. The characteristics of these genera presented in this paper allow their reliable taxonomic identification. Based on the analysis of our experimental data and analyses available in the literature, we propose to combine the genera Alteromonas, Pseudoalteromonas, Idiomarina, and Colwellia into a new family, Alteromonadaceae fam. nov., with the type genus Alteromonas.  相似文献   

19.
Herbarium specimens (c. 1 000) and population samples (76) have been screened for the occurrence of diploid representatives ofTaraxacum sect.Ruderalia (T. sect.Vulgaria, nom. illeg.). The area studied comprises German Democratic Republic, Poland, Czechoslovakia, Hungary and parts of Austria, Yugoslavia, and Rumania. Diploids are common from the Valley of the Moravia river on southwards. Isolated outpost localities are found in S. Poland and extend far to the north: neighbourhood of Berlin. Based on the pattern of distribution in Czechoslovakia, the Pannonian (thermophilous) phytogeographical character of the diploids is discussed. Special attention has been paid to morphological differences between di- and triploids in Czechoslovakia. The study provides a basis for further biosystematical and taxonomic studies in the relationships between diploids and polyploids as well as in the stability of agamospecies.  相似文献   

20.
A yeast strain (CBS 8902) was isolated from the nest of a leaf-cutting ant and was shown to be related to Cryptococcus humicola. Sequencing of the D1/D2 region of the 26S ribosomal DNA and physiological characterization revealed a separate taxonomic position. A novel species named Cryptococcus haglerorum is proposed to accommodate strain CBS 8902 that assimilates n-hexadecane and several benzene compounds. Physiological characteristics distinguishing the novel species from some other members of the C. humicola complex are presented. The phylogenetic relationship of these strains to species of the genus Trichosporon Behrend is discussed. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

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