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1.
Much attention has recently been devoted to the delimitation of species units in Cylindrocladium(Cy.). In this regard the present study focuses on the taxa within the unresolved Cy. floridanum and Cy. spathiphylli species complexes. Maximum parsimony analyses of DNA sequences of ITS, β-tubulin and histone regions of rRNA genes, and mating experiments revealed a geographically isolated species of Cylindrocladium in the Cy. spathiphylli(teleomorph:Calonectria spathiphylli) species complex.Cy. pseudospathiphylli sp. nov. (teleomorph:Ca. pseudospathiphylli sp. nov.) is described as a new phylogenetic, biological and morphological species. It is distinguished from Cy. spathiphylli by being homothallic, having smaller macroconidia, and distinct DNA sequences of β-tubulin and histone genes. Similarly, parsimony analysis of a combined data set also indicated several phylogenetic species to exist within Cy. floridanum(teleomorph:Ca. kyotensis). Based on differences in vesicle morphology and conidium dimensions, the Canadian population of Cy. floridanum, formerly known as Cy. floridanum Group 2, is described as Cy. canadense sp. nov., while a further collection from Hawaii is described as Cy. pacificum sp. nov.  相似文献   

2.
The teleomorph of Aquaphila albicans was discovered on submerged wood collected in Thailand. Its black, soft-textured, setose ascomata, bitunicate asci and hyaline to pale brown, multiseptate ascospores indicated an affinity to Tubeufiaceae (Dothideomycetes). After morphological or molecular comparisons with related species in Tubeufia, Acanthostigma and Taphrophila, it is described and illustrated as a new species, T. asiana Sivichai & K.M. Tsui, sp. nov. Finding this Tubeufia teleomorph was surprising, given the falcate conidia of its A. albicans anamorph, which superficially resemble the conidia of Fusarium and not the coiled, helicosporous conidia of other species in Tubeufiaceae. We assessed the phylogenetic relationships of A. albicans-T. asiana with ribosomal sequences from SSU and ITS and partial LSU regions by parsimony and Bayesian analysis. An initial set of 40 taxa representing a wide range of ascomycete families and their SSU sequences from GenBank showed A. albicans-T. asiana to be nested within the Tubeufiaceae with 100% bootstrap support. Their placement was inferred with ITS and partial LSU ribosomal sequences. The nearly identical ITS sequences of two isolates of A. albicans and one isolate of Tubeufia asiana united these fungi as a monophyletic group with 100% bootstrap support and further nested them, with 88% bootstrap support, in a clade containing Helicoon gigantisporum and Helicoma chlamydosporum. This is the first molecular phylogenetic study to place a nonhelicosporous species within the Tubeufiaceae and to show that helical conidia were lost at least once within the family.  相似文献   

3.
Luque J  Martos S  Phillips AJ 《Mycologia》2005,97(5):1111-1121
Botryosphaeria viticola sp. nov., isolated from pruned canes of Vitis vinifera in NE Spain, is described and illustrated. Phylogenetic analysis based on ITS and EF1-alpha sequences and morphological characters of both anamorph and teleomorph confirmed this taxon to be included within the group of Botryosphaeria species with Dothiorella anamorphs. It is related most closely to B. sarmentorum and B. iberica from which it differs in morphological characters of the teleomorph and DNA sequences.  相似文献   

4.
The phylogenetic relationship of the coelomycete genus Infundibulomyces with cupulate conidiomata was assessed by ribosomal DNA sequences of partial small subunit (SSU) and partial large subunit (LSU) regions using maximum parsimony and Bayesian analysis. The genus has no known teleomorph. A new species, Infundibulomyces oblongisporus, is described from collections on a senescent angiosperm leaf from Thailand based on morphological and phylogenetic evidence. Both Infundibulomyces species form a monophyletic group in the Chaetosphaeriaceae (Chaetosphaeriales, Sordariomycetidae) with Dictyochaeta simplex as a sister clade. Chaetosphaeriaceae with a coelomycete anamorph has not been reported previously.  相似文献   

5.
The taxonomy and systematics of the New Caledonian endemic caddisfly genus Gracilipsodes Sykora, 1967 (Trichoptera: Leptoceridae: Grumichellini) are reviewed. Seven new species represented by males are described and illustrated: Gracilipsodes aoupiniensis sp. nov. , Gracilipsodes aureus sp. nov. , Gracilipsodes aurorus sp. nov. , Gracilipsodes grandis sp. nov. , Gracilipsodes koghiensis sp. nov. , Gracilipsodes lanceolatus sp. nov. , and Gracilipsodes robustus sp. nov. Molecular phylogenetic analyses are applied to discern the relationships among the species of the genus and their closest relatives, based on sequence characters from the nuclear gene translation elongation factor-1α (EF-1α) and the three mitochondrial genes cytochrome oxidase I (COI), COII, and ribosomal large subunit (16S). The data are analyzed using parsimony and Bayesian inference, revealing a monophyletic Gracilipsodes with the eastern Australian monotypic genus Triplexa as its closest relative. Gracilipsodes is in turn divided into two major lineages.  © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society, 2008, 153 , 425–452.  相似文献   

6.
Kang HJ  Sigler L  Lee J  Gibas CF  Yun SH  Lee YW 《Mycologia》2010,102(5):1167-1184
Yellow rot, caused by an ascomycetous fungus having a distinctive arthroconidial anamorph, is the most destructive disease of cultivated Ganoderma lucidum in Korea, but the identity of the yellow rot pathogen (YRP) remains uncertain. Isolates have been identified as Xylogone sphaerospora (with putative anamorph Sporendonema purpurascens) or as Arthrographis cuboidea. Therefore we used morphological features, pathogenicity tests and phylogenetic analyses of DNA sequences from the nuclear ribosomal genes, including partial small subunit and internal transcribed spacer regions, and from the gene encoding RNA polymerase second largest subunit to evaluate the relationship between YRP isolates and these species. YRP isolates formed a distinct subgroup within a clade that included X. sphaerospora, A. cuboidea and Scytalidium lignicola, the type species of Scytalidium, but the disposition of the clade within the Leotiomycetes was uncertain. We describe Xylogone ganodermophthora sp. nov. and Scytalidium ganodermophthorum sp. nov. for the teleomorph and anamorph of YRP respectively. Arthrographis cuboidea is reclassified as Scytalidium cuboideum comb. nov., and the anamorph of X. sphaerospora is named Scytalidium sphaerosporum sp. nov. In pathogenicity tests only X. ganodermophthora caused disease in Ganoderma lucidum. Amplified fragment length polymorphism analyses showed that X. ganodermophthora populations from diseased fruiting bodies or from oak wood in Korea consisted of two clonal groups.  相似文献   

7.
A new species of Pythium collected from grapevine roots (Vitis vinifera) in South Africa and roots of common beet (Beta vulgaris) in Majorca, Spain, is described. The phylogenetic position of the new species was investigated by multigene sequence analyses of the internal transcribed spacers (ITS1 and ITS2) of the rDNA region, as well as three other nuclear and three mitochondrial coding genes. Maximum likelihood phylogenetic analyses based on ITS rDNA and concatenated beta-tubulin and cytrochrome c oxidase II alignment place Pythium recalcitrans together with P. sylvaticum and P. intermedium. Pythium recalcitrans sp. nov. is morphologically almost indistinguishable from other Pythium species that only form hyphal swellings in culture. However its species status is justified by the distinctiveness of the DNA sequences in all the genes examined. In culture P. recalcitrans exhibits fast radial growth, abundant spherical to subglobose hyphal swellings but produces no zoosporangia. Sexual structures are not seen in agar media but form in autoclaved grass blades floated on water. Multiple antheridia (1-7) are encountered with most of them diclinous and crook-necked. Oospores are thin-walled and either aplerotic or plerotic. P. recalcitrans was pathogenic to seedlings of Beta vulgaris and Solanum lycopersicum.  相似文献   

8.
9.
The land snail genus Acrotoma (Clausiliidae) from the western Greater Caucasus is revised and a molecular phylogenetic analysis of the genus is presented. Shells and, as far as known, genitalia of 13 species are described and figured. Two species are described as new to science, i.e., A. vespa sp. nov. and A. enguriensis sp. nov. The diagnostic characteristics are summarized in a table. All locality records are listed and shown in distribution maps. Based on Bayesian, Maximum likelihood and Maximum parsimony analyses of mitochondrial and nuclear DNA sequences we revise the classification of the genus and suggest a division into three subgenera, Iliamneme, Acrotomina and Acrotoma s. str. The radiation of the Acrotoma species in the Pliocene and Quaternary might have been triggered by the orogenesis of the Greater Caucasus, which created habitats, such as canyons and alpine environments, to which the Acrotoma species adapted.www.zoobank.org/urn:lsid:zoobank.org:pub:6B14BE68-0E07-42EF-B08D-A75B2138B72F  相似文献   

10.
Data from microscopic morphology, single-spore cultures, and DNA analyses of teleomorphs and anamorphs support the recognition of five species of Prosthecium with Stegonsporium anamorphs on Acer: P. acerinum sp. nov., the teleomorph of S. acerinum; P. acerophilum comb. nov., formerly known as Dictyoporthe acerophila; P. galeatum comb. nov., originally described as Massaria galeata; P. opalus sp. nov.; and P. pyriforme sp. nov., the teleomorph of S. pyriforme s. str. The morphology of both type specimens and freshly collected material was investigated. The teleomorphs have brown ellipsoidal ascospores with five distosepta and often a longitudinal distoseptum. The anamorphs of all species described here belong to Stegonsporium; their connection to the Prosthecium teleomorphs was demonstrated by morphology and DNA sequences of single spore cultures derived from both ascospores and conidia. The anamorphs and teleomorphs of all five Prosthecium species are described and illustrated by LM images, and a key to these species is provided. As perceived from this work, S. pyriforme is restricted to Europe and does not occur in North America, whereas S. acerinum is restricted to North America, not found in Europe. The host associations given in the literature are revised and evidence is provided that only A. opalus, A. pseudoplatanus, and A. saccharum are confirmed hosts of Prosthecium with Stegonsporium anamorphs. Molecular phylogenetic analyses of tef1, ITS rDNA, and partial nuLSU rDNA sequences confirm that the species with Stegonsporium anamorphs are closely related to P. ellipsosporum, the generic type species. Stilbospora macrosperma is confirmed as the anamorph of P. ellipsosporum by DNA data of single spore isolates obtained from both ascospores and conidia.  相似文献   

11.
Berkleasmium crunisia sp. nov. is described from a decaying rachis of Calamus sp. (Arecaceae) from Khuan Ka Long, Satun Province, Thailand. This Berkleasmium species differs morphologically from other species in possessing subtending cells and larger conidia. The phylogenetic relationship of the genus Berkleasmium among sexual ascomycetes also was examined. Sequence analyses from 18S, 28S and ITS-5.8S rDNA were analyzed phylogenetically under maximum parsimony, Bayesian and neighbor joining criteria. Phylogenies revealed that Berkleasmium is not monophyletic. Berkleasmium micronesicum and B. nigroapicale are related to Westerdykella cylindrica and Sporormia australis, which are members of the family Sporormiaceae (Pleosporales). Other species, including our new taxon, appear to share phylogenetic affinities with other anamorphic fungi, whose classification within the Pleosporales is still obscure. Analyses of 18S, 28S, ITS (+5.8S) rDNA and combined (18S+28S) gene sequences fail to give sufficient phylogenetic resolution within the Pleosporales.  相似文献   

12.
Hong SB  Go SJ  Shin HD  Frisvad JC  Samson RA 《Mycologia》2005,97(6):1316-1329
The variability within Aspergillus fumigatus Fresenius and related species was examined using macro-, micro-morphology, growth temperature regimes and extrolite patterns. In addition, DNA analyses including partial beta-tubulin, calmodulin and actin gene sequences were used. Detailed examination of strains, considered as A. fumigatus earlier, showed that they could be divided into four groups including A. fumigatus sensu stricto, A. lentulus and two new species. The intraspecific genetic variability within A. fumigatus sensu stricto was low, the sequence differences among 23 strains of the species was at most two bases in each partial beta-tubulin and calmodulin gene. However, intraspecific morphological diversity within the species was high and delineation of the species was equivocal. Therefore, beta-tubulin and calmodulin gene sequences could be critical determinants for the delineation of the A. fumigatus sensu stricto species. A. lentulus including isolates from clinical origin, Korean soil and from a dolphin clustered into an isolated group based on beta-tubulin, calmodulin and actin gene sequences, differing from A. fumigatus by morphological characters, growth temperature and extrolite profile. A. lentulus produces the extrolites auranthine, cyclopiazonic acid, a dimeric indole of unknown structure, neosartorin, some pyripyropens, terrein and some tryptoquivalins and tryptoquivalons. Two pair of isolates (CBS 117194, 117186 and 117520, 117519) clustered into separate groups from A. fumigatus and the other Aspergillus section Fumigati species, including the teleomorph Neosartorya, are proposed as two new species. A. fumigatiaffinis spec. nov. produces the extrolites auranthine, cycloechinulin, helvolic acid, neosartorin, palitantin, pyripyropens, tryptoquivalins and tryptoquivalons, and A. novofumigatus spec. nov. produces the extrolites cycloechinuline, helvolic acid, neosartorin, palitantin and terrein.  相似文献   

13.
Seven strains of ballistoconidiogenous yeasts that contain xylose, form Q-10 ubiquinone, propagate by budding and don't produce stalk conidia were isolated from plant leaves collected in Thailand and were found to represent two new species. The taxonomic properties of the two species coincided with the genus Bullera so they are described as Bullera koratensis sp. nov. and Bullera lagerstroemiae sp. nov. In phylogenetic trees based on the nucleotide sequences of 18S ribosomal DNA and the D1/D2 domain of 26S rDNA, these two species are located in the Trichosporonales clade (Cryptococcus humicola-Trichosporon lineage).  相似文献   

14.
Stunt nematodes are characterized by phenotypic plasticity, with overlapping morphology and morphometry leading to potential misidentification. Consequently, the application of integrative taxonomic approaches is useful to species delimitation based on a combination of different perspectives, e.g. morphology and DNA sequences. We conducted nematode surveys in cultivated and natural environments in Spain and the USA, from which we identified 18 known species of the family Telotylenchidae and two new taxa within the studied samples. These species were morphologically, morphometrically, and molecularly characterized. The results of light and scanning electron microscopic observations, and molecular and phylogenetic analysis also allowed two new species to be distinguished, described herein as B itylenchus hispaniensis sp. nov. and T ylenchorhynchus mediterraneus sp. nov. The phylogenetic analysis was carried out using molecular data from nuclear ribosomal DNA genes [D2–D3 expansion segments of the large ribosomal subunit (28S), internal transcribed spacer (ITS), and partial small ribosomal subunit (18S)]. We also provide here a test of alternative hypotheses that confirms the monophyly of both Tylenchorhynchus and Bitylenchus sensu Siddiqi's classification but does not support Fortuner & Luc's conceptual view of Tylenchorhynchus as a large genus. Ancestral state reconstructions of several diagnostic morphological characters using a maximum parsimony approach showed congruence in morphological and molecular evolution for stylet knob inclination and tail tip annulation. Our analysis emphasizes some of the problems related to the taxonomy and phylogeny of nematodes of Telotylenchinae. © 2014 The Linnean Society of London  相似文献   

15.
16.
Four strains of yeasts isolated in Thailand and Taiwan were found to represent four distinct novel species of the ascomycetous anamorphic yeast genus Candida. These strains are located in the Clavispora-Metschnikowia clade in a phylogenetic tree based on the D1/D2 domain sequences of the large subunit rRNA genes. Together with Candida picinguabensis and Candida saopaulonensis, the four novel species constitute a well-separated subclade from other species of the Clavispora-Metschnikowia clade. Three species from Thailand are described as Candida bambusicola sp. nov. (type strain, ST-50(T) = BCC 7750(T) = NBRC 106734(T) = CBS 11723(T)), Candida nongkhaiensis sp. nov. (type strain, ST-95(T) = BCC 8331(T) = NBRC 105874(T) =CBS 11724(T)) and Candida succicola sp. nov. (type strain, ST-631(T) = BCC 15314(T) = NBRC 106736(T) = CBS 11726(T)), respectively, and the species from Taiwan is described as Candida touchengensis sp. nov. (type strain, SY4S03(T) = NBRC 102647(T) = BCRC 23097(T) = CBS 10585(T)).  相似文献   

17.
Phillips A  Alves A  Correia A  Luque J 《Mycologia》2005,97(2):513-529
Botryosphaeria sarmentorum sp. nov. and B. iberica sp. nov. are described and illustrated. These two species are unusual in this genus because of their brown, 1-septate ascospores. Phylogenetic analysis based on ITS and EF1-alpha sequences place them within the clade containing species with Fusicoccum anamorphs. The brown, 1-septate conidia, however, do not conform to Fusicoccum. Therefore phylogenetically and morphologically the anamorphs of these two species belong in a genus distinct from any of the currently accepted anamorph genera assigned to Botryosphaeria. Through a study of the type species of Dothiorella this genus is resurrected to accommodate anamorphs of Botryosphaeria with brown, 1-septate conidia. Botryosphaeria sarmentorum is shown to be the teleomorph of Diplodia sarmentorum, which in turn is transferred to Dothiorella. Otthia quercus is transferred to Botryosphaeria as B. quercicola nom. nov.  相似文献   

18.
Sixteen Pythium isolates from diverse hosts and locations, which showed similarities in their morphology and sequences of the internal transcribed spacer (ITS) region of their rRNA gene, were investigated. As opposed to the generally accepted view, within single isolates ITS sequence variations were consistently found mostly as part of a tract of identical bases (A-T) within ITS1, and of GT or GTTT repeats within the ITS2 sequence. Thirty-one different ITS sequences obtained from 39 cloned ITS products from the 16 isolates showed high sequence and length polymorphisms within and between isolates. However, in a phylogenetic analysis, they formed a cluster distinct from those of other Pythium species. Additional sequencing of two nuclear genes (elongation factor 1 alpha and beta-tubulin) and one mitochondrial gene (nadh1) revealed high levels of heterozygosity as well as polymorphism within and between isolates, with some isolates possessing two or more alleles for each of the nuclear genes. In contrast to the observed variation in the ITS and other gene areas, all isolates were phenotypically similar. Pythium mercuriale sp. nov. (Pythiaceae) is characterized by forming thin-walled chlamydospores, subglobose to obovoid, papillate sporangia proliferating internally and smooth-walled oogonia surrounded by multiple antheridia. Maximum likelihood phylogenetic analyses based on both ITS and beta-tubulin sequence data place P. mercuriale in a clade between Pythium and Phytophthora.  相似文献   

19.
The dothideomycetous fungus Leptosphaeria maculans comprises a complex of species differing in specificity and pathogenicity on Brassica napus. Twenty-eight isolates were investigated and compared to 20 other species of the Pleosporales order. Sequences of the mating type MAT1-2 (23), fragments of actin (48) and beta-tubulin (45) genes were determined and used for phylogenetic analyses inferred by maximum parsimony, distance, maximum likelihood, and Bayesian approaches. These different approaches using single genes essentially confirmed findings using concatanated sequences. L. maculans formed a monophyletic group separate from Leptosphaeria biglobosa. The L. biglobosa clade encompasses five sub-clades; this finding is consistent with classification made previously on the basis of internal-transcribed sequences of the ribosomal DNA repeat. The propensity for purifying and neutral evolution of the three genes was determined using sliding window analysis, a technique not previously applied to genes of filamentous fungi. For members of the L. maculans species complex, this approach showed that in comparison to actin and beta-tubulin, exonic sequences of MAT1-2 were more diverse and appeared to evolve at a faster rate. However, different regions of MAT1-2 displayed different degrees of sequence conservation. The more conserved upstream region (including the High Mobility Group domain) may be better suited for interspecies differentiation, while the more diverse downstream region is more appropriate for intraspecies comparisons.  相似文献   

20.
Cylindrocladium angustatum is described as a new species fromTillandsia introduced with plant material into the U.S.A. from Central America. Koch's postulates are established to prove its pathogenicity to this host. The species is compared with and distinguished fromC. heptaseptatum andC. rumohrae based on morphology, cultural characteristics and phylogenetic analysis of sequence data of the beta-tubulin gene.  相似文献   

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