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1.
《Mycoscience》2014,55(5):329-335
Two new species of hyphomycetes, Arachnophora dinghuensis and Websteromyces inaequale, are described and illustrated from specimens collected on dead branches of unidentified plants in China. Arachnophora dinghuensis is characterized by monoblastic, integrated, terminal, occasionally percurrently extending conidiogenous cells that produce solitary, acrogenous, staurosporous conidia. The conidia are two-celled, irregular, brown, 21–27.5 × 10–17 μm, with a central body that bears 2 or more fertile, brown to pale brown lateral cells, which in turn give rise to 1–3 fertile, conical, hyaline to pale brown arm-cells, 4–6.5 × 3.5–4.5 μm. A microconidial, Selenosporella-like synanamorph occurs at the apex of the arms. Websteromyces inaequale is recognized as the second species in the genus, and differs from the type species, W. verruculosus, in possessing naviculiform, obclavate to ellipsoidal, smooth, larger conidia in unbranched acropetal chains. The hyphomycetes Rhexoacrodictys queenslandica and Solicorynespora sylvatica are reported from China for the first time. A key to Arachnophora species is provided.  相似文献   

2.
《Mycoscience》2014,55(4):299-307
Minimelanolocus bicolorata sp. nov., Paradendryphiopsis elegans sp. nov. and Corynesporella bannaense sp. nov., are described and illustrated. Minimelanolocus bicolorata is unique in possessing the schizolytic conidial secession and solitary, acropleurogenous, holoblastic conidia that are ellipsoidal, 3-euseptate, 30–35 × 7.5–9.5 μm, verruculose, pale brown, with an appendage at each end. Paradendryphiopsis elegans is characterized by monoblastic conidiogenous cells producing short chains of conidia that are 13–30.5 × 4–6.5 μm, 2–3-euseptate and fusiform to obclavate. Corynesporella bannaense is distinguished by terminal and integrated or discrete, monotretic conidiogenous cells that arise as lateral branches from the tip of the conidiophore and solitary conidia that are 12–16-distoseptate, smooth, obclavate, thick-walled, pale brown, and 100–140 × 10–14 μm. Keys to species of Minimelanolocus, Paradendryphiopsis and Corynesporella are provided.  相似文献   

3.
The new hyphomycete genusAvesicladiella with two species,A. britannica sp. nov., type species, andA. microsperma sp. nov., is described and illustrated. Both species are leaf litter microfungi. The genus closely resemblesVesicladiella, Circinotrichum, Gyrothrix, Ceratocladium andVermiculariopsiella, several hyphomycete genera with comparable characters such as superficial hyphal networks; production of setae; absence of conidiophores; lageniform or ampulliform conidiogenous cells; and hyaline aseptate conidia produced in clusters around the apices of conidiogenous cells. The new genus differs from these by its hyaline, septate setae, typical ‘phialidic’ conidiogenous cells, and hyaline, aseptate cylindrical conidia.  相似文献   

4.
Ophiocordyceps unituberculata, a new insect pathogenic fungus from southwestern China, is described using molecular phylogenetic and morphological data. This fungus differs from other Ophiocordyceps species by its enormously long monophialidic conidiogenous cells and a large periclinal protuberance often growing near the apex of conidiogenous cells, single conidia (lanceolate to fusiform) embedded in mucous sheath, and much larger conidial dimensions. Four-locus (nrSSU, nrLSU, tef-1α and rpb1) and ITS data phylogenetic analyses show that O. unituberculata belongs to the Hirsutella nodulosa clade within the genus Ophiocordyceps of Ophiocordycipitaceae and is a separate clade from other allied species. Molecular phylogeny and morphology both strongly support the distinctiveness of this taxon. The interspecific relationships in the H. nodulosa clade are discussed.  相似文献   

5.
Bursitis is a common medical condition that can occur either with or without infection. We present a case of fungal olecranon bursitis in an immunocompetent individual caused by the new species Knoxdaviesia dimorphospora. It is a dematiaceous filamentous fungus characterized by the production of two different conidia: hyaline and cylindrical, which rise up from phialidic conidiogenous cells located in the upper part of differentiated and unbranched conidiophores, and pale brown and ellipsoidal conidia produced by phialidic conidiogenous cells which are born directly on hyphae. In addition to its morphological peculiarities, the novelty of the fungus was confirmed by sequence analysis of the internal transcribed spacer (ITS) regions and D1/D2 domains of the 28S of the nuclear rRNA gene. The fungal infection was confirmed by cytological examination and repeated cultures. The infection was resolved by surgical debridement and drainage, and the patient presented a complete functional recovery 3 months later. The in vitro antifungal susceptibility to this new human opportunist is provided, terbinafine being the drug with the most potent activity.  相似文献   

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7.
Mycochaetophora gentianae, the causal agent of brown leaf spot on gentian (Gentiana scabra), is characterized by its hyaline besom-like sporophore, although its conidiogenesis and phylogenetic position have so far remained unknown. We isolated the causal fungus from a new host, G. triflora, in Iwate, Japan. Both the G. triflora isolate and the ex-type M. gentianae isolate produced symptoms on G. triflora but not on G. scabra. Microscopic observations of the diseased leaves indicated that conidiogenesis was blastic from short conidiophores, and schizolytic secession of conidia left unthickened and inconspicuous conidial scars on the conidiogenous cells. Conidia were catenate, in branched acropetalous chains; secondary conidia were blastically produced from the first or second cell at the base of primary conidium. The G. triflora isolate was identified as M. gentianae because of its identity to the ex-type in characteristics of culture, pathogenicity, and conidia. Phylogenetic analyses using three ribosomal DNA (rDNA) sequences combined [small subunit (SSU) + large subunit (LSU) + 5.8S rDNA] indicated that both isolates clustered with Rhexocercosporidium carotae, and the cluster was placed within Helotiales–Rhytismatales. Additional analyses using internal transcribed spacers including 5.8S rDNA sequences revealed that both isolates were monophyletic and that they were closely related to three helotialean Pseudocercosporella-like hyphomycetous genera: Helgardia, Rhexocercosporidium and Rhynchosporium.  相似文献   

8.
《Mycoscience》2020,61(4):165-171
A verticillium-like fungus forming a whitish colony and mainly solitary phialides that produced fusiform to cylindrical conidia in chains was isolated from uredinia of Phakopsora pachyrhizi, a causal agent of soybean rust. In addition, two similar looking isolates were obtained from Prostigmata mites. Our taxonomic study based on morphology and phylogenetic analysis using ITS rDNA and LSU rDNA D1/D2 region sequences revealed that the three isolates were the same species and assigned to the genus Leptobacillium. These isolates represent a new species, morphologically and phylogenetically distinguished from the type species, L. leptobactrum, and we propose L. symbioticum sp. nov. In addition, Simplicillium chinense and S. coffeanum are assigned to the genus Leptobacillium.  相似文献   

9.
Temperature and Sporulation of Aquatic Hyphomycetes   总被引:9,自引:3,他引:6       下载免费PDF全文
Temperature appears to be an important factor affecting the occurrence and distribution of aquatic hyphomycetes, the dominant leaf litter-decomposing fungi in streams. We compared conidium production by eight species of aquatic hyphomycetes grown on yellow poplar leaves in stream-simulating microcosms at three temperatures (15, 20, and 25°C). The greatest conidium production occurred at 15°C for one species, 20°C for two species, and 25°C for two species. Two species produced similar numbers of conidia at 20 and 25°C, and one species produced similar numbers of conidia at all three temperatures. Linear growth rates were determined on malt extract agar. Six species had the same pattern of temperature responses for growth on malt extract agar as for sporulation on leaves, as shown by the positive correlations between the two parameters at the three temperatures. The species examined also exhibited differences in number of conidia produced from a similar amount of leaf material at a given temperature. These differences appeared to be due primarily to differences in individual conidium mass (determined by weighing conidia produced from cultures), as shown by the relationship of the type Y = k/X (r2 = 0.96), where Y is the number of conidia produced, X is the individual conidium mass in milligrams, and k is a constant empirically determined to be 2.11. This finding supports the hypothesis that aquatic hyphomycetes allocate similar amounts of their resources to reproduction but vary with respect how these resources are partitioned into reproductive units (conidia).  相似文献   

10.
A new species ofMicrosphaeropsis (Sphaeropsidales, Coelomycetes),M. rugospora, is described and illustrated. This fungus is characterized by its rapid growth on common media such as oatmeal and potato-carrot agars; semi-immersed to immersed, nearly globose, papillate pycnidias; pale yellowish brown, translucent, membranaceous peridium; monophialidic, ampulliform conidiogenous cells; and one-celled, dark brown, globose conidia ornamented with distinct tubercles. The holotype was isolated from the cultivated soil in Tanegashima Island, southern Japan.  相似文献   

11.
The genus Fenestroconidia is described to accommodate the new species Fenestroconidia caloplacae. This lichenicolous fungus produces black sporodochia, has conidiogenous cells arranged in chains, and simple, pale brown conidia with a subhyaline guttule-like zone. It is known only from central Spain (Cuenca province), growing in the apothecia of Caloplaca saxicola s.lat.  相似文献   

12.
This paper deals mainly with the conidium ontogenesis and phylogenesis of black yeasts such as E. jeanselmei, E. gougerotii, E. dermatitidis and E. spinifera. The conidium ontogenesis of E. jeanselmei, E. gougerotii and E. dermatitidis was almost the same. One to five annellated tips were observed through a scanning microscope at the apices of conidiogenous cells, which were bottle- or jar-shaped. Annellations on the tips looked like fringes and the conidiogenous cells of these three species were annellides. Annellated projections occurred on hyphae and annelloconidia were also produced from them. Occasionally, secondary annellides occurred from primary ones. They looked like moniliform hyphae. Daughter conidia sometimes budded directly from mother cells. The shapes and sizes of the conidia of these species were very similar to each other. The conidium ontogenesis of E. spinifera was annellidic as well. However, a single annellated tip usually occurred on an annellide. The annellated tips of the fungus were long and more than 20 annellations were observed on their walls. The conidiogenesis of the four species of Exophiala is only annellidic. There were no differences in the biological examinations except KNO3 assimilation among these four species. The growth of E. jeanselmei and E. gougerotii was poor at 37 degrees C. The GC contents of E. jeanselmei 1171, E. gougerotii B-1800, E. dermatitidis MM-7 and E. spinifera DU-3342 were 54.6, 54.6, 56.6 and 59.7%, respectively.  相似文献   

13.
《Mycological Research》2006,110(7):790-800
Two new nematode-trapping fungi, Dactylellina sichuanensis and D. varietas from China, which capture nematodes by both adhesive knobs and non-constricting rings, are described and illustrated. D. sichuanensis is characterized by both adhesive knobs and non-constricting rings, solitary conidiophores and 3-(4)-6 septate conidia, as compared with species such as D. appendiculata, D. candida, D. leptospora and D. lysipaga. Although D. sichuanensis shares similar types of trapping devices, the presence of simple conidiophores and spindle-shaped conidia with these species, it can be distinguished by its larger conidia and presence of more than four septa. In D. sichuanensis, a single conidium is born at the tip of conidiophore, while in D. candida, 3–10 conidia are born near the apex of conidiophore in a capitate arrangement. It produces spindle-shaped conidia with 3–6 septa, whereas D. leptospora produces cylindrical-shaped conidia with 5–15 septa. D. appendiculata captures nematodes by adhesive knobs whereas D. sichuanensis captures nematodes by both adhesive knobs and non-constricting rings. They also differ in conidial size (35–82.5 μm in D. sichuanensis as compared with 57–108 μm in D. appendiculata). D. varietas is characterized by conidiophores that are branched at right-angles, and elongate to fusoid conidia, with 7–8 septa (more than 25% of which are curved). D. varietas resembles D. asthenopaga, Dactylella oxyspora and Monacrosporium multiseptatum, but has elongate-fusoid conidia, whereas D. asthenopaga possesses obconical or clavate conidia. D. varietas forms both adhesive knobs and non-constricting rings whereas Dactylella oxyspora does not produce any trapping device. M. multiseptatum differs from D. varietas in having larger conidia with an inflated middle cell. Phylogenetic analyses based on nuclear and protein coding DNA sequences (18 S, and a combined 28 S + 5.8 S + β-tubulin dataset) indicate that these two taxa should be assigned to the family Orbiliaceae.  相似文献   

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16.
Conidiogenesis of the type species and two additional species of the genus Raffaelea Arx & Hennebert are described. In contrast to previous conclusions based on light microscopy that indicate sympodial production of the conidia, we found that conidium development was by annellidic percurrent proliferation in the type species Raffaelea ambrosiae, as well as in Raffaelea arxii and Raffaelea albimanens. Consequently, this mode of conidium development is similar to the conidiogenesis of anamorphs within the Ophiostomatales, but distinguished by sporodochia formed within the genus Raffaelea. These findings reduce the differences between Raffaelea and other anamorphs with annellidic percurrent proliferation of the conidiogenous cells within the Ophiostomatales to different conidiomata and conidiophores, and they support previous reports of the close phylogenetic relationship between Raffaelea and Ophiostoma.  相似文献   

17.
The new generic names Codonmyces and Lichenostella are introduced for two new species of conidial fungi. Lichenostella hypotrachynae gen. et sp. nov. is a commensal of Hypotrachyna species, and is mainly characterized by forming black sporodochia with setae and, particularly, by its star-like conidia. Codonmyces lecanorae gen. et. sp. nov. occurs on Lecanora valesiaca and differs from the genus Xanthoriicola by its 1-septate conidia and campanulate conidiogenous cells with several conspicuous, flared annellations. Comments on the ecology ofL. valesiaca , and its associated lichens and lichenicolous fungi are also given.  相似文献   

18.
《Mycoscience》2014,55(2):108-112
Powdery mildew Phyllactinia (Ovulariopsis cf. insolita) is reported on Funastrum clausum and Fcynanchoides in Sinaloa, Mexico. The fungus was reported as Oidium insolitum on Lycium chilense in Argentina, later as Phyllactinia chubutiana (anamorph Ovulariopsis insolita). This fungus was studied by light microscopy and molecular techniques. Fungal mycelium was smooth, effuse, with septate hyphae; appressoria distinct, or ramified; conidiophores pseudoidium type; mature conidium cingulum-like, subcylindric with sub-apical and sub-terminal protuberances. Two rDNA ITS nucleotide sequences were 99% homolog with P. chubutiana's sequence.  相似文献   

19.
S. Kaneko  T. Kobayashi 《Mycoscience》2002,43(2):0181-0183
Three Cylindrosporella species on the leaves of betulaceous trees – C. carpini, C. coryli, and C. microsperma – were first reported from Japan. The genus Cylindrosporella is sometimes treated as congeneric with Asteroma; however, we considered these to differ based on conidial morphology following the concept of Arx. The genus Cylindrosporella is characterized by one-celled, filiform or fusiform, small conidia that are often curved, have hyaline, thin walls, and are produced from phialidic conidiogenous cells in subcuticular, fiat acervuli. The three species are distinguished from each other on the basis of conidium size. Received: September 27, 2001 / Accepted: November 5, 2001  相似文献   

20.
Conidia of Torula caligans (Batista & Upadhyay) M. B. Ellis comb.nov. and T. terrestris Misra were examined by transmission- and scanning-electron microscopy. Torula caligans produced four-celled conidia in which the central cells were distinctly larger than the basal and apical cells. Conidia of T. terrestris were 4- to 7-celled long and ellipsoidal in shape. Conidiogenous cells in both species developed melanin only within the lowermost part of the lateral walls while the other cells of the conidium were uniformly melanized around the circumference of the cell; melanin in these cells being deposited within, at least, half the width of the cell wall. In both species new conidia arose from evagination of the hyaline apex of the conidiogenous cell and are therefore blastoconidia. The systematic relationships between T. caligans and T. terrestris and other species of the genus Torula are discussed.  相似文献   

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