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1.
    
In this study, we investigated the morphology and molecular phylogeny of four marine or brackish spirotrichean ciliates found in China, namely: Caryotricha sinica sp. nov., Prodiscocephalus orientalis sp. nov., P. cf. borrori, and Certesia quadrinucleata. Caryotricha sinica is characterized by its small size, seven cirral rows extending posteriorly to about 65% of the cell length, and four transverse cirri. Prodiscocephalus orientalis differs from its congeners mainly by the number of cirri in the “head” region and on the ventral side. The SSU rDNA sequence of P. cf. borrori differs from that of other population of P. borrori by ca. 40 bp. Consequently, the nominal species P. borrori is considered to be a species-complex. New data are provided for Certesia quadrinucleata. The Chinese population of C. quadrinucleata, for example, has fewer left marginal cirri than the other populations for which such data are available. Phylogenetic analyses based on SSU rDNA sequence data show that the genus Caryotricha is monophyletic. All typical “discocephalids” with a discoid “head” form a strongly supported clade that is sister to the unstable uronychiids + pseudoamphisiellids clade within the Euplotia. The genus Certesia forms a sister group to the Euplotes clade, also within the Euplotia assemblage.  相似文献   

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3.
A new species,Oreocharis xieyongii T.Deng,D.G.Zhang & H.Sun,from Hunan Province,central China,is described.The combination of purple zygomorphic corolla with longer adaxial lobes and exserted stamens defines the species and discriminates it from all other current Oreocharis species.Morphological traits of the new species were compared to those of two similar species,Oreocharis xiangguiensis and 0.rubrostriata.Phylogenetic analysis indicates that the new species is nested within the Oreochari...  相似文献   

4.
Two new species, Neosartorya shendaweii and N. tsunodae, isolated from soil in Xinjing, China and in Pernambuco, Brazil, are described and illustrated. The first species is characterized by its ascospores with two widely separated equatorial crests and tuberculate to verrucose convex surfaces. This species has affinities with several known species of the genus, bearing ascospores with a similar ornamentation, but can be distinguished from these species by other morphological characteristics such as smaller cleistothecia and conidiophores, spathulate vesicles and rather ellipsoidal conidia. The second species is characterized by its unique ascospores with two low equatorial crests, an evident furrow as a deep depression, and finely reticulate convex surfaces. The validation of these new species is supported further by analyses of the β-tubulin, calmodulin and actin gene sequences.  相似文献   

5.
利用活体观察和蛋白银染色技术对近年来采自青岛、大亚湾、湛江沿岸水体的10个海洋寡毛类纤毛虫种:侧扁急游虫Strombidium apolatum Wilbert & Song,2005、具头急游虫Strombidium capitatum (Leegaard,1995) Kahl,1932、广东急游虫Strombidium guangdongense Liu,et al.,2016、拟卡氏急游虫Strombidiumparacalkinsi (Lei,et al.,1999) Agatha,2004、拟楔尾急游虫Strombidium parastylifer Song,et al.,2009、铃木急游虫Strombidium suzukii Song,et al.,2009、束腰旋游虫Spirostrombidium cinctum (Kahl,1932) Petz,et al.,1995、杨科夫平游虫Parallelostrombidium jankowski (Song,et al.,2009) Song,et al.,2018、卡尔平游虫Parallelostrombidium kahli (Song,et al.,2009) Song,et al.,2018、最小拟盗虫Strombidinopsis minima (Gruber,1884) Song & Bradbury,1998的形态学开展了比较研究,补充和厘定了有关形态特征、纤毛图式以及性状变异等分类学新信息。  相似文献   

6.
    

A summary of recent studies on the interrelationships of pterodactyloid pterosaurs is used as a framework for reassessing the taxonomic status of Zhejiangopterus, a new, long‐necked, Late Cretaceous pterosaur from China that has been assigned to the Nyctosauridae. Characters cited in support of this decision include: a notarium, edentulous jaws, and lack of a cranial crest. However, none of these is diagnostic of the Nyctosauridae. Zhejiangopterus exhibits a number of derived characters (orbit relatively small and located in a low position, posteroventrally facing occiput, features of the humerus and ‘T‐shaped’ cross‐section of wing phalanges two and three) only otherwise found in azhdarchids, thus we propose that Zhejiangopterus be reassigned to the Azhdarchidae.  相似文献   

7.
本研究利用活体观察和蛋白银染色方法对采自西藏日喀则和那曲的3种苔藓栖生纤毛虫,鬃异源棘尾虫(Tetmemena pustulata)、棘毛虫未定种(Sterkiella sp.)和殖口虫未定种(Gonostomum sp.)进行了形态学研究,描述了活体、核器以及纤毛图式等形态学特征.同时,测定了这3种纤毛虫的SSU r...  相似文献   

8.
Xylodon subflaviporus (Hymenochaetales, Basidiomycota) is described as a new species collected from tropical and subtropical regions of East Asia. This new species is characterized by resupinate basidiocarps, a poroid hymenophore, pseudodimitic hyphal system, nodose-septate hyphae, four types of cystidia (capitate, acicular to cylindrical, subulate to ventricose, and apically-encrusted), and thin-walled, colorless, smooth and ellipsoid basidiospores. Bayesian, Maximum Likelihood and Maximum Parsimony algorithms were used to construct phylogenies inferred from the internal transcribed spacer (ITS) region of rDNA. Morphological and molecular studies, along with intercompatibility tests, confirmed the independent status of this species. Also, based on morphological and molecular evidence, six new combinations of Xylodon are proposed to accommodate species originally classified under Hyphodontia s.l., i.e. X. bubalinus, X. chinensis, X. mollissimus, X. nongravis, X. reticulatus and X. subtropicus. A key to known species of Hyphodontia s.l. with poroid, irpicoid or raduloid hymenophores is provided for the convenience in identification.  相似文献   

9.
微孢子虫(Microsporidia)是一类专性细胞内寄生的单细胞真核生物,在科研、医疗、农业、商业等领域具有重要影响。由于其不具有某些典型的真核生物细胞结构,如线粒体、过氧化物酶体、高尔基体、鞭毛,曾将其归属于古真核生物谱系,认为其进化历程先于这些细胞器的起源,该假说也得到了一些生物化学和分子生物学研究证据的支持。然而,在最近十年里,通过更深入的研究,尤其是基于分子序列的系统进化分析,表明微孢子虫和真菌具有一定亲缘关系,并认为其结构的简约性恰好体现了微孢子虫营寄生生活的高度退化现象。目前对微孢子虫的系统进化仍存在各种不同意见,对其进化研究历史进行探讨有着重要意义。本文将按照时间顺序回顾微孢子虫进化分类研究过程中的各种研究成果,并讨论为什么微孢子虫独特的细胞和基因组特性会导致众多的学者在其进化分类问题上争执这么久。  相似文献   

10.
Ophiostoma spp. (Ophiostomatales, Ascomycota) are well-known fungi associated with bark and ambrosia beetles (Curculionidae: Scolytinae, Platypodinae). Fungi in the Ophiostomatales include serious tree pathogens as well as agents of timber blue-stain. Although these fungi have been extensively studied in the northern hemisphere, very little is known regarding their occurrence on hardwoods in Europe. The aims of the present study were to identify and characterize new Ophiostoma spp. associated with bark and ambrosia beetles infesting hardwoods in Norway and Poland, and to resolve phylogenetic relationships of Ophiostoma spp. related to the Norwegian and Polish isolates, using multigene phylogenetic analyses. Results obtained from five gene regions (ITS, LSU, β-tubulin, calmodulin, translation elongation factor 1-α) revealed four new Ophiostoma spp. These include Ophiostoma hylesinum sp. nov., O. signatum sp. nov., and O. villosum sp. nov. that phylogenetically are positioned within the Ophiostoma ulmi complex. The other new species, Ophiostoma pseudokarelicum sp. nov. reside along with Ophiostoma karelicum in a discrete, well-supported phylogenetic group in Ophiostoma s. stricto. The results of this study clearly show that the diversity and ecology of Ophiostoma spp. on hardwoods in Europe is poorly understood and that further studies are required to enrich our knowledge about these fungi.  相似文献   

11.
    
Currently choanoflagellates are classified into two distinct orders: loricate Acanthoecida and non-loricate Craspedida. The morphologically based taxonomy of the order Craspedida is in need of a revision due to its controversial, paraphyletic and inconsistent systematics and nomenclature. In this study, we add molecular data (SSU and parts of the LSU rDNA) of six new Craspedida species isolated from saline, brackish and freshwater habitats to the existing knowledge. Four of these six organisms could be described as new species: Paramonosiga thecata, “Salpingoeca” euryoecia, “Salpingoeca” ventriosa, “Sphaeroeca” leprechaunica, whereas two are assigned to previous morphologically described species: “Salpingoeca” fusiformis Saville Kent, 1880 and “Salpingoeca” longipes Saville Kent, 1880. Paramonosiga is established as a new genus of the Craspedida based on its phylogenetic position. Extending the dataset by six additional sequences shows that the craspedid taxonomy is still unsolved as the type specimen Salpingoeca gracilis has not yet been sequenced and hence a clear assignment to the genus Salpingoeca is not possible. Trying to assign morphological and ecological data to phylogenetic clades is not successful. We give an improved/emended morphological diagnosis for the two redescribed species and add molecular data for all six species, shedding light on their phylogenetic position.  相似文献   

12.
Coltriciella minuscula sp. nov. is described and illustrated from a specimen collected on Pinus merkusii from Bogor, Indonesia. This species is characterized by the size of its basidiocarp up to 4 mm in diam, with long hair on the stipe and with ornamented spores. Both morphological distinctiveness and phylogenetic separation based upon analyses of nrDNA ITS sequences support the establishment of this new species. Morphological dissimilarities between C. minuscula and closely related species are discussed.  相似文献   

13.
    
《Mycoscience》2014,55(2):79-88
Aspergillus caatingaensis and A. pernambucoensis, isolated from semi-desert soil in caatinga area, the State of Pernambuco, Brazil, are described and illustrated. Aspergillus caatingaensis is characterized by its white cleistothecia, broadly lenticular ascospores with four equatorial crests and irregularly ribbed to slightly reticulate with aculeate convex surfaces, and ellipsoidal to broadly ellipsoidal conidia with a smooth wall. Aspergillus pernambucoensis is characterized by its, white cleistothecia, lenticular ascospores with two equatorial crests and irregularly ribbed with tuberculate to verrucate convex surfaces, and ovoid to broadly ellipsoidal conidia with a smooth wall. The validation of these new species is supported further by analyses of the β-tubulin, calmodulin and actin gene sequences.  相似文献   

14.
麂属(Muntiacus)的分类及其系统发育研究   总被引:7,自引:1,他引:7  
麂属(Muntiacus)是一群中小型草食有蹄类,为东洋界的特有属,是典型的热带、亚热带类群。在我国,麂属的分布仅限于长江流域及其以南各地,为我国南方的重要毛皮兽。 以往对麂属的研究多限于一般的形态分类,对其系统发育尚未深入研究。在种级分类上至今还存在一些混乱现象。本文试图用分支系统学(Cladistics)的方法,对麂属的种级分化进行系统整理,并对其系统发育作一初步探讨。  相似文献   

15.
《Mycoscience》2014,55(3):213-220
Aspergillus huiyaniae, a new teleomorphic species isolated from desert soil in Xinjiang, China, was described and illustrated. Aspergillus huiyaniae is characterized by its yellowish white to pale yellow cleistothecia, broadly lenticular ascospores with two equatorial crests and irregularly ribbed to slightly reticulate convex surfaces, and subglobose to ovate or broadly ellipsoidal conidia with smooth walls. This species was supported further by the analyses of the β-tubulin, calmodulin and actin gene sequences.  相似文献   

16.
报道了在云南西南部发现的凤仙花属一新种——滇红凤仙花(Impatiens quintadecimacopii G.W.Hu&Q.F.Wang)和一新记录种——伸展凤仙花(I.porrecta Wall.ex Hook.f.&Thomson)。这两个种在形态上很相似,但在花色、侧萼片形状、旗瓣形状和蒴果颜色上明显有别。根据形态特征,这两个种应属于凤仙花亚属(I. subg.Impatiens)单花组(I. sect.Uniflora)。结合核糖体DNA内转录间隔区序列(ITS)与叶绿体atpB-rbcL间隔区序列开展系统发育分析,结果进一步确认了这两个种关系紧密,以及它们在单花组内的系统位置。  相似文献   

17.
    
《Mycoscience》2018,59(6):467-472
A new aquatic fungus was isolated from submerged, decaying leaves collected at Phu Quoc Island in Vietnam. The fungus produced hyaline, unique-shaped conidia consisting of a hook-shaped main axis and three arms at the helicoid part of the main axis. Based on its conidial development and morphological characteristics, Hamatispora phuquocensis was newly introduced. Phylogenetic analyses based on LSU nrDNA sequences showed that it clusters with Microthyrium spp. and belongs to Microthyriales. Furthermore, we generated ITS barcode for this hyphomycetous fungus.  相似文献   

18.
    
《Palaeoworld》2020,29(4):682-694
A conodont fauna from the uppermost part of the Beiliu Formation at the Nalai section (Guangxi, South China) is studied. Four species of Bipennatus Mawson are described, of which B. hemilevigatus n. sp. is differentiated by a short sulcus flanked by a smooth left margin and a nodose right margin, and B. planus n. sp. is characterized by a distinctly flat, smooth, and narrow platform in the middle part of the blade above the basal cavity. Another species in open nomenclature, Bipennatus? sp., is distinguished by an extremely primitive sulcus or a totally fused and adenticulate ridge above the basal cavity. This paper also reports occurrences of ‘Ozarkodina’? sp. B, Polygnathus nalaiensis n. sp., and P. costatus costatus Klapper. The conodont fauna situates the investigated samples in the lower Eifelian costatus Zone. Taking specimens of Bipennatus from the Hillesheimer Mulde and Bergischen Land (Germany) into consideration, the conodont material furnishes new data on the diversification and phylogeny of this genus. A taxonomic revision of Bipennatus is conducted, and this genus includes B. bipennatus (Bischoff and Ziegler), B. hemilevigatus, B. montensis (Weddige), B. planus, B. scalaris (Mawson), and B. mayri (Uyeno), the latter two are raised herein to species level. More importantly, the prominent diversification of Bipennatus in the costatus Zone cannot be interpreted by previously proposed hypotheses on the phylogeny of Bipennatus, which specifically focus on the development of a characteristic sulcus on the upper margin above the basal cavity. It is apparent that the ornamentation of the narrow or wide platform above the basal cavity is more complicated and variable than previously estimated, and that this genus needs further investigation, especially on the lowest occurrences of its assigned species.  相似文献   

19.
    
《Mycoscience》2014,55(6):456-461
Two new species, Melanoleuca leucopoda and M. porphyropoda, are described based on collections made from Shenyang City, Liaoning Province, China. Melanoleuca leucopoda is mainly characterized by its whitish stipe with fibrils and oblong spores with elongated warts. Melanoleuca porphyropoda differs from all other Melanoleuca species in lacking cystidia and in having decurrent gills and a purplish stipe. The sequences of internal transcribed spacer regions (ITS1-5.8S-ITS2) of Melanoleuca species were analyzed and the results indicated that two new species clustered into two clades and differed from the other species of the genus. The combination of morphological and molecular data confirmed that the two fungi are new species. The morphological similarity of the new species to other species of Melanoleuca and the systematic position of the two species based on molecular data are also discussed.  相似文献   

20.
    
《Mycoscience》2014,55(4):289-298
Two new species of Heterobasidion, H. amyloideum and H. tibeticum, are described and illustrated from eastern Himalayas. Both species are closely related to the Heterobasidion insulare complex in morphology, but they differ in presence of cystidia and amyloid skeletal hyphae in the context. Phylogenetically, the combined RPB1 and RPB2 sequence data supports H. amyloideum and H. tibeticum as two distinct species within the H. insulare complex.  相似文献   

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