Mononematous Conidiophores Research Articles

Cordana yunnanensis sp. nov., Isolated from Desertified Rocky Soil in Southwest China.

During a survey of soil fungal diversity in a rocky desertification area in Yunnan Province, China, a new dematiaceous hyphomycete, Cordana yunnanensis was identified. Morphologically, this species is characterized by macronematous, mononematous conidiophores with discrete, polyblastic conidiogenous cells arranged in a whorl at the apices. Phylogenetic analysis of the combined sequences of the internal transcribed spacer and the large nuclear ribosomal RNA subunit confirmed the phylogenetic position of C. yunnanensis within the genus Cordana, in Cordanaceae.

Pleocatenatachiangraiensis gen. et. sp. nov. (Pleosporales, Dothideomycetes) from medicinal plants in northern Thailand.

Pleocatenata, a new genus, is introduced with its type species, Pleocatenatachiangraiensis, which was isolated from withered twigs of two medicinal plants, Clerodendrumquadriloculare (Blanco) Merr (Verbenaceae) and Tarennastellulata (Hook.f.) Ridl (Rubiaceae) in northern Thailand. The genus is characterized by mononematous, septate, brown or dark brown conidiophores, monotretic conidiogenous cells and catenate, obclavate, olivaceous to blackish brown conidia. Phylogenetic analysis of combined LSU, SSU, tef1-α, rpb2 and ITS sequence data showed Pleocatenata forms a distinct phylogenetic lineage in Pleosporales, Dothideomycetes. Therefore, we treat Pleocatenata as Pleosporales genera incertae sedis based on morphology and phylogenetic analyses. Descriptions and illustrations of the new taxa are provided, and it is compared with morphologically similar genera.

Morphological and phylogenetic characterisations reveal three new species of Samsoniella (Cordycipitaceae, Hypocreales) from Guizhou, China.

Samsoniella species have been found on lepidopteran larvae or pupae buried in soil or leaf litter. Three new species, Samsoniella hymenopterorum, S. coleopterorum and S. lepidopterorum, parasitic on hymenopteran larvae, coleopteran larvae and lepidopteran pupae, respectively, are reported. Morphological comparisons with extant species and DNA-based phylogenies from analysis of a multigene (ITS, RPB1, RPB2 and TEF) dataset supported the establishment of the new species. Unusually, all three new species have mononematous conidiophores. The new species are clearly distinct from other species in Samsoniella occurring in separate subclades.

Chromelosporium re-evaluated, with Chromelosporiopsis gen. nov. and Geohypha stat. nov.

Chromelosporium-like asexual morphs of the subterraneous Pezizaceae in the /Pachyphlodes clade are not congeneric with the type of Chromelosporium. Some Chromelosporium morphs are of species in the /Pezizaceae clade (the /Peziza clade), and the genus Chromelosporium as it has been defined is polyphyletic. A diagnostic character that distinguishes these two groups is the presence or absence of conidiophore fasciculation. Mononematous conidiophores characterize Chromelosporium and species related to the /Peziza clade. Synnematous conidiophores characterize Pachyphlodes and other asexual species and define the new genus Chromelosporiopsis, to be excluded from Chromelosporium. Hyphelia terrestris, long misapplied to Chromelosporium, is revaluated, lectotypified, redescribed and recombined as Geohypha terrestris.

<p><strong><em>Akanthomyces lepidopterorum</em></strong><strong>, a new lecanicillium-like species</strong></p>

During a survey of entomopathogenetic fungi from Southwest China, a new species, Akanthomyces lepidopterorum was found on an undetermined lepidopteran larva. It differs from other species based on mostly smaller conidia, mononematous conidiophores and moderate length of phialide. Both the morphological identification and phylogenetic analysis of combined ITS, LSU and RPB2 sequence data support A. lepidopterorum as a new species. A new combination is also proposed in the genus Akanthomyces.

Distoseptispora bambusae sp. nov. (Distoseptisporaceae) on bamboo from China and Thailand.

BackgroundBamboo is a widespread plant with medicinal value. During our taxonomic study on medicinal plants, three collections of Distoseptispora were made from China and Thailand. Phylogenetic analyses of combined LSU, ITS and RPB2 sequence data showed that two collections represented a new species, phylogenetically distinct from other described species in Distoseptispora.New informationThis new species has macronematous, mononematous conidiophores, polyblastic or monoblastic conidiogenous cells and acrogenous, solitary, straight, obclavate, multi-septate, thick-walled conidia. Distoseptispora bambusae sp. nov. is introduced with illustrations and a comprehensive description. The third collection on dead wood from Thailand was identified as D. tectona with newly-generated molecular data for this taxon.

Natonodosa speciosa gen. et sp. nov. and rediscovery of Poroisariopsis inornata: neotropical anamorphic fungi in Xylariales

Natonodosa is introduced as new genus based on morphology and multigene phylogenetic data, and the monotypic genus Natonodosa, typified by N. speciosa, is characterized by mononematous conidiophores, polyblastic, nodose conidiogenous cells and unicellular, fusiform, hyaline conidia. The other freshly collected material was identified as Poroisariopsis inornata, a species that since its original description had not been reported; it is characterized by synnematous conidiophores with polytretic, cylindrical and uncinate conidiogenous cells with percurrent extensions, and distoseptate, obclavate, brown conidia. A lectotype and an epitype for the species are established and referred since the original specimen of this microfungus has not been found in any herbarium. Placement of both taxa in Xylariales was ascertained by BLASTn searches. Maximum likelihood analysis of the combined sequence data of the ribosomal rDNA (ITS and partial LSU region), as well as partial gene regions coding for the second largest subunit of RNA polymerase II (RPB2) and beta-tubulin (TUB2), was performed. In addition, a new name, Guarroa, is proposed for replacing the illegitimate genus name Phaeobotrys M. Calduch, Gene & Guarro. A dichotomous key to the new genus and morphologically similar taxa is provided.

Akanthomyces araneicola, a new araneogenous species from Southwest China

During a survey of spider-pathogenic fungi from Southwest China, a new araneogenous species was found. The new species, Akanthomyces araneicola, differs from other species based on mostly smaller fusiform conidia (2.5–5.0 × 1.3–1.9 μm), mononematous conidiophores and, additionally, in parasitising a spider. Both the morphological identification and phylogenetic analysis of combined ITS, LSU, RPB1, RPB2 and TEF sequence data support A. araneicola as a new species in the genus Akanthomyces.

Aquimonospora tratensis gen. et sp. nov. (Diaporthomycetidae, Sordariomycetes), a new lineage from a freshwater habitat in Thailand

An interesting hyphomycetous taxon was collected on submerged wood in a freshwater stream in Trat Province, Thailand. It is morphologically similar to endophragmiella-like taxa, characterized by macronematous, mononematous conidiophores, monoblastic, enteroblastic conidiogenous cells and clavate to obovoid, septate brown conidia. The unique feature of this taxon is that the mature conidium often bears a young new conidial primordium which develops percurrently from a lower semi-transparent cell and they secede simultaneously. Phylogenetic analyses of a combined LSU, SSU and RPB2 sequence data support the placement of this fungus together with Platytrachelon and close to the family Papulosaceae within Diaporthomycetidae, Sordariomycetes. A new genus is introduced to accommodate the new taxon as Aquimonospora. The novel species Aquimonospora tratensis is described and illustrated and is compared with other morphologically similar taxa.

Three new Leptographium spp. (Ophiostomatales) infecting hardwood trees in Norway and Poland

Species of Leptographium are characterized by mononematous or synnematous conidiophores and are commonly associated with different arthropods. Some of them also produce a sexual state characterised by globose ascomata with elongated necks. Compared to investigations on coniferous trees, the occurrence of Leptographium species on hardwood trees has been poorly studied in Europe. During a survey of ophiostomatoid fungi on various hardwood tree species in Norway and Poland, three unusual species, which fit in the broader morphological description of Leptographium spp., were found in association with Trypodendron domesticum, Trypodendron signatum and Dryocoetes alni, and from wounds on a variety of hardwoods. Phylogenetic analyses of sequence data for six different loci (ITS1–5.8 S–ITS2, ITS2-LSU, ACT, β-tubulin, CAL, and TEF-1α) showed that these Leptographium species are phylogenetically closely related to the species of the Grosmannia olivacea complex. The first species forms a well-supported lineage that includes Ophiostoma brevicolle, while the two other new taxa resided in a separate lineage; possibly affiliated with Grosmannia francke-grosmanniae. All the new species produce perithecia with necks terminating in ostiolar hyphae and orange-section shaped ascospores with cucullate, gelatinous sheaths. These species also produce dark olivaceous mononematous asexual states in culture. In addition, two of the newly described species have a second type of conidiophore with a short and non-pigmented stipe. The new Leptographium species can be easily distinguished from each other by their appearance and growth in culture. Based on novel morphological characters and distinct DNA sequences, these fungi were recognised as new taxa for which the names Leptographium tardum sp. nov., Leptographium vulnerum sp. nov., and Leptographium flavum sp. nov. are provided.

Two new Leptographium spp. reveal an emerging complex of hardwood-infecting species in the Ophiostomatales.

Species of Leptographium are generally characterized by mononematous conidiophores and are commonly associated with bark beetles and weevils. These species are responsible for sapstain and in some cases serious diseases on a range of primarily coniferous trees. In comparison with coniferous trees, the occurrence of Leptographium species on hardwood trees has been poorly studied in Europe. During a survey of ophiostomatoid fungi on various tree species in Norway and Poland, three unusual species, which fit the broader morphological description of Leptographium spp., were found in association with Scolytus ratzeburgi, Dryocoetes alni and Trypodendron domesticum on a variety of hardwoods, and from wounds on Tilia cordata. Phylogenetic analyses of sequence data for three gene regions (ITS2-LSU, β-tubulin, and TEF1-α) showed that these Leptographium species are phylogenetically closely related to each other and form a well-supported lineage that included Grosmannia grandifoliae and Leptographium pruni. The first species could be distinguished from the other Leptographium species based on conidiophores arising from spiral hyphae, chlamydospore-like structures and a hyalorhinocladiella-like synanamorph in culture. The second species differs from the previous one by having distinctly shorter conidiophores and smaller conidia. This species also produces a well-developed sporothrix-like synanamorph with denticulate conidiogenous cells. Based on these unusual morphological characteristics and distinct DNA sequences, these fungi were recognised as new taxa for which the names Leptographium trypodendri sp. nov. and L. betulae sp. nov. are provided. The third group of isolates belonged to Grosmannia grandifoliae, representing the first report of this species outside of the USA. The newly defined G. grandifoliae complex is the first species complex in Leptographium s.l. consisting of only hardwood-infecting species.

The genus Fusariella

The genus Fusariella, typified by F. atrovirens, is characterised by semi- to macronematous, mononematous conidiophores, with cylindrical, subulate or lageniform phialidic conidiogenous cells that produce catenate, septate, curved to straight, subhyaline to brown conidia. During a survey of hyaline-spored hyphomycetes from karst areas in Thailand, we collected a new species of Fusariella with curved conidia and introduce it in this paper as Fusariella curvata sp. nov. In addition, all hitherto described species of Fusariella are reviewed. The result of phylogenetic analyses, based on combined SSU, LSU, TEF and RPB2 sequence data, indicates that the genus belongs in the family Bionectriaceae (Hypocreales, Sordariomycetes).

Penicillium albobiverticillium sp. nov., a new species producing white conidial masses from biverticillate penicillia.

Penicillium albobiverticillium is described as a new species belonging to the genus Penicillium, subgenus Biverticillium mainly due to the following characteristics: white conidial masses, acerose phialides, mononematous conidiophores with biverticillate penicillia, and a red soluble pigment on CYA, MEA, and MA. A spontaneous mutant obtained from a colony sector is also described. It produces a huge amount of blood-red, viscous exudate on MEA and an abundant red soluble pigment on CYA, MEA, and MA.

Endosporoideus gen. nov., a mitosporic fungus on Phoenix hanceana

Endosporoideus pedicellata gen. et sp. nov. is described and illustrated from decaying petioles of Phoenix hanceana collected from grassland in Tai Mo Shan, Hong Kong. The genus is unique in producing solitary, phragmosporous conidia. The conidia comprise a brown to dark brown inner-wall layer and thick, hyaline outer-wall layer and are produced holoblastically from determinate conidiogenous cells on micronematous, mononematous conidiophores. Cells of conidia may disarticulate at the septa. Representative steps in conidiogenesis of E. pedicellata are illustrated with light micrographs, and details of the conidiogenous events are interpreted schematically.

Endosporoideus gen. nov., a mitosporic fungus on Phoenix hanceana

Endosporoideus pedicellata gen. et sp, nov. is described and illustrated from decaying petioles of Phoenix hanceana collected from grassland in Tai Mo Shan, Hong Kong. The genus is unique in producing solitary, phragmosporous conidia. The conidia comprise a brown to dark brown inner-wall layer and thick, hyaline outer-wall layer and are produced holoblastically from determinate conidiogenous cells on micronematous, mononematous conidiophores. Cells of conidia may disarticulate at the septa. Representative steps in conidiogenesis of E. pedicellata are illustrated with light micrographs, and details of the conidiogenous events are interpreted schematically.

New hyphomycetes from Restionaceae in fynbos: Parasarcopodium ceratocaryi gen. et sp. nov., and Rhexodenticula elegiae sp. nov.

Two new hyphomycetous anamorphs were isolated from plant hosts of the Restionaceae in the fynbos of the Cape Floral Kingdom of South Africa. Parasarcopodium ceratocaryi gen. et sp. nov. on Ceratocaryum decipiens produces aseptate, cylindrical conidia with amorphous mucoid appendages at both ends in rows or whorls of phialides on verruculose, mononematous conidiophores. Rhexodenticula elegiae sp. nov. on Elegia capensis produces pale brown, fusiform or broadly fusiform, 3-septate conidia on denticles located in the upper part of smooth, geniculate conidiophores. The morphological characteristics of both taxa are described, illustrated, and contrasted to other morphologically similar fungi. To elucidate the phylogenetic relationships of Parasarcopodium, partial large subunit rRNA (28S) gene sequence was generated from the ex-type strain, which revealed it to be a member of the Bionectriaceae (Hypocreales).

Phylogenetic relationships among Phialocephala species and other ascomycetes

Phialocephala was established for species in the Leptographium complex that produce conidia from phialides at the apices of dark mononematous conidiophores. Some species previously included in Phialocephala were re-allocated to Sporendocladia because they resembled Thielaviopsis in having ring-wall-building conidial development and conidia with two attachment points that emerge in false chains. Despite this significant realignment of the genus, a great deal of morphological heterogeneity remains in Phialocephala. The objective of this study was to consider the heterogeneity among Phialocephala spp. based on comparisons of sequence data derived from the large and small subunits (LSU and SSU) of the rRNA operon of species in Phialocephala. Phialocephala dimorphospora, the type species of the genus, and P. fortinii grouped with genera of the Helotiales in phylogenetic trees generated based on the LSU and SSU datasets. Phialocephala xalapensis and P. fusca clearly are unrelated to Phialocephala sensu stricto and should represent a new genus in the Ophiostomatales. Phialocephala compacta resides with representatives of the Hypocreales, and we believe that it represents a distinct genus. Phialocephala scopiformis and P. repens are not closely related to the other Phialocephala species and group within the Dothideales. The morphological heterogeneity among species of Phialocephala clearly is reflected by phylogenetic analysis of sequence data from two conserved rRNA gene regions. Appropriate genera now need to be found to accommodate these fungi.

Phylogenetic Relationships among Phialocephala Species and Other Ascomycetes

Phialocephala was established for species in the Leptographium complex that produce conidia from phialides at the apices of dark mononematous conidiophores. Some species previously included in Phialocephala were re-allocated to Sporendocladia because they resembled Thielaviopsis in having ring-wall-building conidial development and conidia with two attachment points that emerge in false chains. Despite this significant realignment of the genus, a great deal of morphological heterogeneity remains in Phialocephala. The objective of this study was to consider the heterogeneity among Phialocephala spp. based on comparisons of sequence data derived from the large and small subunits (LSU and SSU) of the rRNA operon of species in Phialocephala. Phialocephala dimorphospora, the type species of the genus, and P. fortinii grouped with genera of the Helotiales in phylogenetic trees generated based on the LSU and SSU datasets. Phialocephala xalapensis and P. fusca clearly are unrelated to Phialocephala sensu stricto and should represent a new genus in the Ophiostomatales. Phialocephala compacta resides with representatives of the Hypocreales, and we believe that it represents a distinct genus. Phialocephala scopiformis and P. repens are not closely related to the other Phialocephala species and group within the Dothideales. The morphological heterogeneity among species of Phialocephala clearly is reflected by phylogenetic analysis of sequence data from two conserved rRNA gene regions. Appropriate genera now need to be found to accommodate these fungi.

Phylogenetic relationships in Leptographium based on morphological and molecular characters

Species of Leptographium Lagerberg & Melin are characterized by mononematous conidiophores with dark stipes and conidiogenous apparatuses with complex series of branches. These fungi generally inhabit woody substrates, are associated with bark beetles (Coleoptera: Scolytidae) and cause blue-stain in conifers. Few phylogenetic studies have been conducted on Leptographium species, and those that have been undertaken have been focused on a small number of species. The objective of this study was to investigate the phylogenetic relationships among species in Leptographium based on partial DNA operon sequences and to ascertain whether morphological characters are congruent with DNA-based phylogeny. Morphological characters were analyzed and compared with results from DNA sequence analysis. Results indicate that there are three groups within Leptographium based on DNA sequence analysis. There was, however, no congruence between these groups and those emerging from morphological characters. Data from this study strongly support the connection between Leptographium and Ophiostoma Sydow & Sydow. They also provide us with an objective means to confirm the identity of many Leptographium species that are difficult to distinguish based on morphological characters.Key words: Leptographium, phylogeny, morphology, Ophiostoma, rRNA.

Phylogenetic relationships in <i>Leptographium</i> based on morphological and molecular characters

Species of Leptographium Lagerberg & Melin are characterized by mononematous conidiophores with dark stipes and conidiogenous apparatuses with complex series of branches. These fungi generally inhabit woody substrates, are associated with bark beetles (Coleoptera: Scolytidae) and cause blue-stain in conifers. Few phylogenetic studies have been conducted on Leptographium species, and those that have been undertaken have been focused on a small number of species. The objective of this study was to investigate the phylogenetic relationships among species in Leptographium based on partial DNA operon sequences and to ascertain whether morphological characters are congruent with DNA-based phylogeny. Morphological characters were analyzed and compared with results from DNA sequence analysis. Results indicate that there are three groups within Leptographium based on DNA sequence analysis. There was, however, no congruence between these groups and those emerging from morphological characters. Data from this study ...