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1.
中国北京地区的多孔菌   总被引:9,自引:1,他引:8  
本文报道产于中国北方北京地区的非褶菌目孔状真菌72种,并列出了每种的寄主。其中大部分种类为该地区首次报道。王氏薄孔菌为一新种,它的主要特征为子实体平伏反转,孔口表面奶油色至浅黄色,担孢子圆柱型并略弯曲,生长在李属树木上。该新种与垫状薄孔菌相似,但后者孢子较宽且是完全平伏的种类。  相似文献   

2.
Five new species of Crotonia from New Zealand ( C. cervicorna, C. cupulata, C. longibulbula, C. tuberculata and C. reticulata ) are described as new, and two species ( C. cophinana (Michael 1908) and C. caudatis (Hammer 1966)) are redescribed. Five species groups of the genus are characterized and a key to the adequately described species of the world is presented.  相似文献   

3.
Three sections of Calceolaria (Scrophulariaceae) in NW South America are revised, viz. sect. Urticopsis (8 species in the area), Lobatae (4), and Micranthera (2). Sect. Urticopsis is characterized by herbaceous, ovate, petiolate leaves and white to buffish pubescence. Sect. Lobatae is characterized by lobate, petiolate leaves and white to greyish white pubescence. Sect. Micranthera comprises small herbs with a weedy habit, characterized by small anthers and unusually long filaments. Three new species are described, viz. C. obtusa, C. trichanthera , and C. adenocalyx (all in sect. Urticopsis) , and one new combination is made, viz. C. penlandii ssp. puraceensis (sect. Urticopsis). Chromosome numbers (all 2n = 36) are reported for C. lamiifolia, C. obtusa, C. penlandii ssp. penlandii , and C. dichotoma.  相似文献   

4.
Sect. Zygophylla of Calceolaria (Scrophulariaceae) in NW South America is revised. It is characterized by connate leaves with winged petioles, and most of the species have intercalary inflorescences. Fourteen species are recognized in the investigated area, one of which is described as new, viz. C. zamorana. Two new combinations are made, viz. C. nevadensis ssp. meridensis (Pennell) Molau and C. purpurascens (Kranzlin) Molau. The chromosome number 2n = 36 is reported for six of the species, viz. C. calycina, C. dilatata, C. grandiflora, C. lanata, C. lojensis , and C. trilobala. The species of sect. Zygophylla are completely interfertile, and sympatric species are isolated by external barriers, e.g. pollination and habitat ecology. Several cases of natural hybridization and introgression are reported.  相似文献   

5.
The genus Cyclocodon Griff. was reduced by C. B. Clarke in 1881 into a section of the genus Campanumoea. Our LM and SEM observations on pollen morphology show that the pollen of all the three species in the former is 3-colporate with the exine sparsely high-spinulose, whereas that of the two species in the latter is 5~8-colpate with the exine relatively densely short-spinulose. SEM observations on seed-coat indicate that the primary ornamentation of the seed-coat of the two species in Campanumoea (s. str. ) is characterized by regular and polygonal areoles which are much larger than the radial walls in diameter and by the bead-like secondary ornamentation on the radial walls, while that of the three species in Cyclocodon is characterized by irregular-shaped areoles which are nearly equal to the radial walls in diameter and by the rope-like secondary ornamentation on the radial walls. Thus, the pollen morphology is closely correlated with the seed-coat morphology. Taking the characteristics of pollen, seed-coat and gross morphology into consideration, the genus Cyclocodon is restored, separate from Campanumoea (s. str. ). One new combination, Cyclocodon celebicus (B1.)Hong, is made in the present paper. The genus Cyclocodon is con-sidered closely related to Platycodon rather than to Campanumoa.  相似文献   

6.
Chorigyne is described as a new genus, characterized by distichous leaves with bifid lamina, free pistillate flowers, four subapical placentas, and fusiform seeds. It is most closely related to Sphaeradenia and Stelestylis. The generic relationships, and the restricted distribution of Chorigyne in Costa Rica and Panama, are discussed. Five species are described as new, viz. C. densiflora, C. pterophylla, C. paucinervis, C. cylindrica , and C. tumescens. Furthermore, two new combinations are made, viz. C. ensiformis and C. pendula. A key to the species is given, each species is described, and the new ones are illustrated.  相似文献   

7.
A new genus of cellular slime molds, Copromyxella, is described together with four species that comprise it. Since it resembles Zopf's Copromyxa more than any genus presently recognized, but differs from it in important characteristics such as the smaller dimensions of its cellular elements and the delicacy of its fructifications, the name Copromyxella is chosen for the new taxon. Four species are included: C. silvatica, C. filamentosa, C. spicata, and C. coralloides. All are characterized by small myxamoebae with lobose and potentially “explosive” pseudopodia and may assume limax forms in liquid media; all possess nuclei with centrally positioned nucleoli; all lack true contractile vacuoles (with a single possible exception); all aggregate without stream formation; and all form fructifications with no demarcation into stalks and sori. Taxonomically the genus belongs in the Acrasidae with Copromyxa, Guttulinopsis and Acrasis rosea rather than in the better known Dictyostelidae that includes Dictyostelium and Polysphondylium.  相似文献   

8.
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   

9.
Phototaxis and gravitaxis are characterized in a freshwater species of the flagellate Cryptomonas. The phototactic orientation in this limnetic species is unusual and differs from all other Cryptomonas species studied so far: At both low (< or = 1O W m-2) and higher fluence rates it orients perpendicular to the light beam (diaphototaxis) while another freshwater Cryptomonas species (strain CR-1) is restricted to positive phototaxis and the marine species, C. maculata, shows both a positive and a more pronounced negative phototaxis. The mechanism of light direction detection seems to depend on a periodic shading or irradiation mechanism as confirmed by the disturbance of phototaxis in the presence of high viscosity media. In addition, this freshwater species possesses a rather pronounced negative gravitaxis which is only partially modified by phototaxis. The ecological consequences of this behavior are discussed.  相似文献   

10.
Neptunia natans is a unique aquatic legume indigenous to tropical and sub-tropical regions and is nodulated symbiotically by rhizobia using an unusual infection process unlike any previously described. Previously, isolates of neptunia-nodulating rhizobia from Senegal were characterized as Allorhizobium undicola. Here we report on a different group of neptunia-nodulating rhizobia isolated from India. Sequencing of the 16S rDNA gene from two of these Indian isolates (strains J1T and J2) show that they belong in the genus Devosia rather than Allorhizobium. Currently, the only described Devosia species is D. riboflavina (family Hyphomicrobiaceae, order Rhizobiales). The complete 16S rDNA sequences of strains J1T and J2 are 95.9% homologous to the type strain, D. riboflavina LMG 2277T, suggesting that these neptunia-nodulating strains from India belong to a new Devosia species. This hypothesis was confirmed by further studies of polyphasic taxonomy (DNA-DNA hybridisation, TP-RAPD patterns, SDS-PAGE of cellular proteins, 16S rDNA RFLP patterns, carbon source utilisation, cellular fatty acid analysis and other phenotypic characterisations), all of which support the proposal that these neptunia-nodulating strains constitute a new Devosia species, which we name Devosia neptuniae sp. nov. These gram negative, strictly aerobic short rods are motile by a subpolar flagellum, positive for catalase, oxidase, urease and beta-galactosidase, can utilise several carbohydrates (but not organic acids) as carbon sources and contain C18:0 3-OH, cis-7 C18:1 11-methyl and cis-7 C18:1 as their major cellular fatty acids. Unlike D. riboflavina, the longer-chain C24:1 3-OH and C26:1 3-OH hydroxy fatty acids are not detected. The type strain of D. neptuniae is LMG 21357T (CECT 5650T). Assignment of this new taxon represents the fourth example in the literature of a non-rhizobial genus of bacteria capable of forming a bonafide dinitrogen-fixing root-nodule symbiosis with legume plants.  相似文献   

11.
Recently discovered strong nucleosomes (SNs) are characterized by strongly periodical DNA sequence, with visible rather than hidden sequence periodicity. In a quest for possible functions of the SNs, it has been found that the SNs concentrate within centromere regions of A. thaliana chromosomes . They, however, have been detected in Caenorhabditis elegans as well, although the holocentric chromosomes of this species do not have centromeres. Scrutinizing the SNs of C. elegans and their distributions along the DNA sequences of the chromosomes, we have discovered that the SNs are located mainly at the ends of the chromosomes of C. elegans. This suggests that, perhaps, the ends of the chromosomes fulfill some function(s) of centromeres in this species, as also indicated by the cytogenetic studies on meiotic chromosomes in spermatocytes of C. elegans, where the end-to-end association is observed. The centromeric involvement of the SNs, also found in A. thaliana, opens new horizons for the chromosome and centromere structure studies.  相似文献   

12.
Asgari B  Zare R 《Mycologia》2011,103(4):863-882
Twenty-one species of Chaetomium known from Iran were compared on the basis of morphological and molecular characters. Six new species are recognized, five isolated from cereals and one from nematode cysts. A combined sequence dataset of the ITS region, partial LSU rDNA, and β-tubulin gene sufficiently resolved five species groups of Chaetomium that are largely concordant with combined features of peridium structure, ascospore shape and germ pore position. Among the new species C. undulatulum is a close relative of C. globosum, C. rectangulare is close to C. elatum, C. interruptum and C. grande are close to C. megalocarpum, altogether forming the C. globosum species group. Chaetomium iranianum and C. truncatulum are members of the C. carinthiacum species group, characterized by spirally coiled ascomatal hairs and fusiform ascospores. A chrysosporium-like anamorph is newly described for C. acropullum.  相似文献   

13.
峨眉山自然保护区的虫草及其它昆虫病原真菌Ⅰ.   总被引:1,自引:0,他引:1  
采自四川省峨眉山自然保护区的虫草及其相关昆虫病原真菌,其中除有常见的蛹虫草Cordycepsmilitaris(Vuill.)Fr,粉被虫草(CordycepspruinosaPetch),蝉拟青霉Paecilomycescicadae(Miquel)Samson,球孢白僵菌Beauveriabassiana(Bals.)Vuill等昆虫病原真菌外,将主要描述峨眉虫草新种(CordycepsemeiensisA.Y.LiuetLiangsp.nov.),龙洞虫草新种(CordycepslongdongensisA.Y.LiuetLiangspnov.),暗绿虫草新记录种(CordycepsatrovirensKob.etShim.)和蛹虫草球头变种新记录种Cordycepsmilitarisvar.sphaerocephala(Schw)Fr.等几种虫草菌。  相似文献   

14.
A new, soil-associated species of the genus Debaryomyces, D. udenii, is described. The species is characterized by pusticulate rather than verrucate ascospores, and slowly lytic asci.  相似文献   

15.
Beladjal  Lynda  Mertens  Johan 《Hydrobiologia》1997,359(1-3):101-111
Chirocephalus ponticus n.sp. (Crustacea: Anostraca) from Turkey is described. The new species is characterized by the form of the second antenna and the frontal appendages of the male. This species seems to be related to C. turkestanicus Daday. Furthermore, analysis of limb structure reveals differences between the three Chirocephalus species previously known from Turkey: C. paphlagonicus, C. vornatscheriand C. diaphanus. New localities for these species are reported. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

16.
The morphological characteristics of 35 wild plant species were studied after freezing of seeds under the conditions of deep, fast, and programmed freezing (-196 degrees C) and non-deep freezing (-10 degrees C). The seeds were stored frozen for a month. The seeds of all the species were characterized by a low humidity. The field and laboratory seed germination capacity, leaf growth, the quantity and length of shoots, the quantity of generative organs, and the variability of these characteristics were studied. It was shown that the direction of changes under different cooling conditions was the same except for the laboratory germination capacity of some species. The direction was determined by the species features rather than cooling conditions.  相似文献   

17.
Réblová M  Seifert KA 《Mycologia》2004,96(2):343-367
The genus Cryptadelphia (Trichosphaeriales) is described for the presumed teleomorphs of six species of the dematiaceous hyphomycete genus Brachysporium. Cryptadelphia is characterized by the production of dark, leathery perithecia with two-layered walls, cylindrical, long-stipitate asci with eight hyaline, initially aseptate but ultimately 1-septate as-cospores. Zigno?lla groenendalensis is transferred to Cryptadelphia with Wallrothiella melanostigmoides as a synonym. Five new species, i.e., Cryptadelphia abietis, C. brevior, C. obovata, C. pendulispora and C. polyseptata, with their respective Brachysporium anamorphs, are described and illustrated. Phylogenetic analysis of partial large subunit rDNA sequences of two species supports the monophyly of Cryptadelphia and suggests a relationship with the Trichosphaeriales. The monophyly of the Trichosphaeriaceae and the relationships between the Trichosphaeriaceae, Annula-tascaceae and the Sordariales can be questioned, but a conclusive assessment requires phylogenetic analysis of more related taxa. The genus Wallrothiella is redescribed based on new collections of W. congregata and is characterized by the production of tiny, globose ascospores in cylindrical asci. The new collection is proposed as a neotype for the genus.  相似文献   

18.
Abstract. A revision and phylogenetic analysis of the Neotropical genus Chimarrhodella Lestage is presented. Four described species are recognized, C.galeata (Martynov), C.peruviana (Ross), C.ulmeri (Ross) and C.nigra Flint. In addition, five new species are described, C.costaricensis sp.n. (Costa Rica), C.tapanti sp.n. (Costa Rica), C.flinti sp.n. (Venezuela), C.pilcopata , sp.n. (Peru) and C.tobagoensis sp.n. (Tobago). These species are organized into two monophyletic species groups, designated here the Galeata Group and the Peruviana Group. The Galeata Group is characterized by having male genitalia with tergum X possessing well developed lateral lobes bearing sclerotized, spine-like processes and includes C.galeata, C.costaricensis, C.flinti, C.pilcopata and C.tapanti. The Peruviana Group is characterized by having male genitalia with tergum X only slightly divided apically, tergum IX bearing hook-like processes posteriorly, and female genitalia with segment VIII much elongated in comparison to the Galeata Group and includes C.peruviana, C.nigra, C.tobagoensis and C.ulmeri. Records of the genus from Costa Rica and Tobago represent significant extensions of the known range for the genus, previously unknown north of Panama. A key to males and known females and a species-level phylogenetic analysis are included.  相似文献   

19.
Two new species ofConiochaeta, isolated from Japanese soils, are described and illustrated:C. cephalothecoides, which is characterized by dark brown ascomata clothed with short setae, cylindrical asci and ovoid to almond-shaped or pyriform ascospores with a longitudinal germ slit; andC. dumosa, which is characterized by dark brown ascomata clothed with short setae and dense hyphal hairs, cylindrical asci and ellipsoid-fusoid ascospores with a longitudinal germ slit. These species are distinguished from most species of the genus by the unique cephalothecoid peridium of their ascomata. The associated anamorphs of both species are assignable to the form-genusLecythophora.  相似文献   

20.
In addition to describing a new species, Cypripedium wumengense, as well as a new variety, C. bardolphianum var. zhongdianense, nomenclatural and taxonomic notes are made on its allies and the division to which they belong. They are ltrge]y found in the Hengduan Mountains in southwestern China, characterized by the absence of bract, havirg lip more or less covered with small wart-like outgrowths, and that as the capsule matures the scape becomes much elongated. Six species of this group have hitherto been reported, of which, however, C. ebracteatum and C. nutans are regarded here as conspecific with C. fargesii and C. bardolphianum respectively. Thus, including the new taxa described here, it composes five species and one variety: C. bardolphianum W. W. Sm. et Farrer (var. bardolphianum and var. zhongdianense S. C. Chen), C. micranthum Franch., C. fargesii Franch., C. margaritaceum Franch. and C. wumengense S. C. Chen. They are all grouped here into the same section, Sect. Trigonopedium (Franch.) Pfitz., the oldest legitimate name of this group in the rank of section.  相似文献   

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