Anamorphic Taxa Research Articles

A reappraisal of orders and families within the subclass Chaetothyriomycetidae (Eurotiomycetes, Ascomycota)

The subclass Chaetothyriomycetidae (Eurotiomycetes, Ascomycota) is an assemblage of ecologically diverse species, ranging from mutualistic lichenised fungi to human opportunistic pathogens. Recent contributions from molecular studies have changed our understanding of the composition of this subclass. Among others, ant-associated fungi, deep-sea fungi and bryophilous fungi were also shown to belong to this group of ascomycetes. The delimitation of orders and families within this subclass has not previously been re-assessed using a broad phylogenetic study and the phylogenetic position of some taxa such as the lichenised family Celotheliaceae or the Chaetothyrialean bryophilous fungi is still unclear. In our study, we assemble new and published sequences from 132 taxa and reconstruct phylogenetic relationships using four markers (nuLSU, nuSSU, mtSSU and RPB1). Results highlight several shortfalls in the current classification of this subclass, mainly due to un-assigned paraphyletic taxa. The family Epibryaceae is therefore described to circumscribe a previously un-assigned lineage. Celotheliales ad int. is suggested for the lineage including the lichen genus Celothelium and various plant pathogens. The delimitation of the family Trichomeriaceae is also broadened to include the genus Knufia and some anamorphic taxa. As defined here, Chaetothyriomycetidae includes four orders (Celotheliales ad int., Chaetothyriales, Pyrenulales, and Verrucariales) and ten families (Adelococcaceae, Celotheliaceae, Chaetothyriaceae, Cyphellophoraceae, Epibryaceae fam. nov., Herpotrichiellaceae, Pyrenulaceae, Requienellaceae, Trichomeriaceae, and Verrucariaceae).

The phylogenetic placement of hypocrealean insect pathogens in the genus Polycephalomyces: An application of One Fungus One Name

Understanding the systematics and evolution of clavicipitoid fungi has been greatly aided by the application of molecular phylogenetics. They are now classified in three families, largely driven by reevaluation of the morphologically and ecologically diverse genus Cordyceps. Although reevaluation of morphological features of both sexual and asexual states were often found to reflect the structure of phylogenies based on molecular data, many species remain of uncertain placement due to a lack of reliable data or conflicting morphological characters. A rigid, darkly pigmented stipe and the production of a Hirsutella-like anamorph in culture were taken as evidence for the transfer of the species Cordyceps cuboidea, Cordyceps prolifica, and Cordyceps ryogamiensis to the genus Ophiocordyceps. Data from ribosomal DNA supported these species as a single group, but were unable to infer deeper relationships in Hypocreales. Here, molecular data for ribosomal and protein coding DNA from specimens of Ophiocordyceps cuboidea, Ophiocordyceps ryogamiensis, Ophiocordyceps paracuboidea, Ophiocordyceps prolifica, Cordyceps ramosopulvinata, Cordyceps nipponica, and isolates of Polycephalomyces were combined with a broadly sampled dataset of Hypocreales. Phylogenetic analyses of these data revealed that these species represent a clade distinct from the other clavicipitoid genera. Applying the recently adopted single system of nomenclature, new taxonomic combinations are proposed for these species in the genus Polycephalomyces, which has been historically reserved for asexual or anamorphic taxa.

Diversity of lignicolous and Ingoldian fungi on woody litter from the River Kali (Western Ghats, India)

Three hundred and sixty woody litter samples naturally deposited in a stream and dammed section of the River Kali in southwest India were assessed for the diversity of lignicolous fungi (ascomycetes and anamorphic fungi) via damp chamber incubation and aquatic hyphomycetes (Ingoldian fungi) via bubble chamber incubation. Fifty-six fungal taxa were recorded with the highest of 47 taxa in the stream and 34 taxa in the dam. Twenty-five taxa were common to both sites. The core group (≥10%) comprised one ascomycete (Massarina australiensis), two anamorphic taxa (Acrogenospora sphaerocephala and Sporoschisma saccardoi) and 11 Ingoldian fungi (Anguillospora crassa, A. longissima, Clavariana aquatica, Cylindrocarpon sp., Flagellospora curvula, F. penicillioides, Lunulospora curvula, L. cymbiformis, Lunulospora sp., Triscelophorus acuminatus, T. monosporus). The species richness, average taxa per wood sample, richness of core group fungi and fungal diversity were higher in the Kaiga stream than in the Kadra dam. Species abundance curves showed higher frequency of occurrence of fungi in the stream than in the dam woody litter. The rarefaction indices of fungal species against number of wood samples revealed similar pattern of ascomycetes in both locations, while the richness of anamorphic and Ingoldian taxa was higher in the stream than in the dam. The anamorph/teleomorph ratio ranged between 2.4:1 (Kadra dam) and 3.3:1 (Kaiga stream), which is higher than the ratios reported from other geographical locations (0.7:1−2:1). This study reconfirmed that the method of incubation influences the assessment of fungal communities in woody litter and that Ingoldian fungi also constitute an important component of woody litter.

Fungi associated with leaf litter of para rubber (Hevea brasiliensis)

The objective of this research was to study the diversity of fungi associated with the degradation of para rubber leaf litter. Samples were collected at three periods in 2010: January (during the late rainy season), April (during the dry season) and July (early in the rainy season) in Nakhon Si Thammarat and Songkhla Provinces, both in southern Thailand. Each sample comprised the following three groups; newly fallen leaves, middle stage decaying leaves and old decaying fallen leaves. Moist chamber and dilution pour-plate methods were used. Fungal identification was based on morphological examination under compound and stereo microscopes. A total of 447 species of fungi were identified from the para rubber leaf litter, comprising 405 anamorphic taxa, 38 ascomycetes, two zygomycetes, one oomycete and one basidiomycete. Cladosporium tenuissimum was the dominant species in newly fallen leaves. Kirschsteinothelia sp., Nigrospora sphaerica and Veronaea coprophila were the dominant species in middle stage decaying leaves. In addition to Kirschsteinothelia sp., Lasiodiplodia cf. theobromae, Panchanania jaipurensis, Subulispora procuvata and Veronaea coprophila were the dominant species in old decaying fallen leaves.

The polyphyletic nature of Pleosporales: an example from Massariosphaeria based on rDNA and RBP2 gene phylogenies

Massariosphaeria is a loculoascomycetous fungus currently accommodated within the Pleosporales. However, based on morphology alone, it has been difficult to assess its familial position and its affinities to other fungi with bitunicate asci. In order to establish its evolutionary relationships, two regions of the rDNA (18S and 28S) and two regions of the RPB2 protein-coding gene were sequenced and analysed phylogenetically. Multigene phylogenies revealed that Massariosphaeria is not monophyletic and results are in disagreement with existing morphological-based classification schemes. Characters, such as ascomatal shape and ascospore morphology, have evolved more than once within the Pleosporales. The familial placement of several species is still obscure, except M. grandispora, which could be confidently assigned to the Lophiostomaceae. M. typhicola is closely related to Trematosphaeria hydrela ( Melanommataceae), whereas M. triseptata is related to Melanomma radicans but shares close affinities to the Sporormiaceae. The placement of M. roumeguerei is still unresolved, and it does not appear to have any close evolutionary relationship to any known melanommataceous or pleosporaceous genera. Our molecular data also refute the monophyly of Kirschsteiniothelia, Massarina, Melanomma, and Pleospora, and support previous phylogenetic hypotheses that Melanommataceae is polyphyletic. There is a need for more phylogenetic (and taxonomic) studies within the Pleosporales, especially incorporation of more anamorphic taxa and type species.

Enzymatic activity of endophytic fungi of six native seedling species from Doi Suthep-Pui National Park, Thailand.

Endophytic fungi were isolated from the stems, petioles, midribs, and leaves of seedlings of six native tree species collected from Doi Suthep-Pui National Park, Thailand. Endophytes were isolated from all tissue samples investigated, and taxa included five ascomycetes, eight anamorphic taxa, and numerous sterile mycelia. Twenty-six strains were tested for their ability to produce cellulase, mannanase, proteinase, and xylanase. The ability to produce these enzymes was distributed amongst the strains tested. Rainforest seedlings supported a diverse array of endophytes that have a wide range of enzymatic activities. The implication of enzyme production in relation to lifestyle abilities of the endophytes is discussed.

Dark septate endophytes: a review of facultative biotrophic root-colonizing fungi.

Dark septate root endophytes (DSE) are conidial or sterile fungi (Deuteromycotina, Fungi Imperfecti) likely to be ascomycetous and colonizing plant roots. They have been reported for nearly 600 plant species representing about 320 genera and 100 families. DSE fungi occur from the tropics to arctic and alpine habitats and comprise a heterogeneous group that functionally and ecologically overlaps with soil fungi, saprotrophic rhizoplane-inhabiting fungi, obligately and facultatively pathogenic fungi and mycorrhizal fungi. Numerous species of undescribed sterile and anamorphic taxa may also await discovery. Although DSE are abundant in washed root and soil samples from various habitats, and are easily isolated from surface-sterilized roots of ecto-, ectendo-, endo- and non-mycorrhizal host species, their ecological functions are little understood. Studies of DSE thus far have yielded inconsistent results and only poorly illustrate the role of DSE in their natural habitats. These inconsistencies are largely due to the uncertain taxonomic affinities of the strains of DSE used. In addition, because different strains of a single anamorph taxon seem to vary greatly in function, no clear generalizations on their ecological role have been drawn. This paper reviews the current literature on DSE and the ecology and discusses the need for and direction of future research.