Roland Kirschner

Cuniculitrema polymorpha (Tremellales, gen. nov. and sp. nov.), a heterobasidiomycete vectored by bark beetles, which is the teleomorph of Sterigmatosporidium polymorphum.

In a study of the mycobiota associated with bark beetles, a dimorphic fungus producing longitudinally septate basidia of the Tremella-type and yeast cells budding off from stalks, was collected. Detailed morphological, physiological and molecular studies revealed that this fungus represents the teleomorph of Sterigmatosporidium polymorphum. Consequently, a new genus, Cuniculitrema gen. nov., and a new species, C. polymorpha sp. nov., are proposed. Comparative morphological and molecular studies indicated that the new taxon belongs to a group that also comprises species of the stalk-forming anamorphic genera Fellomyces and Kockovaella. The new family Cuniculitremaceae is proposed for this group.

Minimizing the chaos following the loss of Article 59: Suggestions for a discussion

We assert that the suppression at the 2011 Melbourne Botanical Congress of the dual nomenclature for pleomorphic fungi was premature since most fungal genera still remain inadequately typified and need molecularly based revisions. The new system turns a rule-determined nomenclature into a system of names to be decided by committees. The new system cannot be implemented until experts publish well-documented rationales about the generic names to be accepted or suppressed among alternative morphs and the responsible committees act officially. Prioritization vs. suppression is not the same as conservation vs. rejection. If a teleomorphic generic name is suppressed, it still remains valid and legitimate and can still serve as a basis for names of higher-rank taxa. In most cases the teleomorph genus name should be prioritized unless convincing arguments favor preference of the anamorph name. Paraphyletic genera must be recognized. Unless the phylogenetic positions of all type species for possible morphs are confirmed, no prioritization can be fixed. When a binomial in a prioritized genus has a younger epithet than the corresponding name in the suppressed genus, only priority of extant names in the prioritized genus should count.

Taxonomic re-evaluation of the Ceratobasidium-Rhizoctonia complex and Rhizoctonia butinii, a new species attacking spruce.

A taxonomic re-evaluation of the Ceratobasidium-Rhizoctonia group suggests that Ceratobasidium contains only the type species C. calosporum, which deviates in micromorphological and ultrastructural characters from all other species so far included in that genus. Rhizoctonia species are compared with the type species of Ceratobasidium, Cejpomyces, Oncobasidium, Tofispora, Waitea, and Ypsilonidium. The micromorphology, ultrastructure, cellular interaction with the host, and molecular phylogeny of a Rhizoctonia species parasitic on needles and young shoots of Picea abies have been studied. The parasite has been known for a long time, but misinterpreted, and not named so far. Rhizoctonia butinii is described and compared with related species of the genus.

Cercosporella and Ramularia

Cercosporella and Ramularia (hyphomycetous anamorphs with relationship to Mycosphaerellaceae, Ascomycota) are difficult to distinguish based on light microscopic characteristics of conidiophores and conidia. Although both genera have been known for more than 120 y, new morphological characteristics were found by “simple” light and scanning electron microscopy now allowing an unambiguous differentiation between both genera. Newly discovered morphological characteristics of interaction structures and ultrastructure of conidiogenous loci are congruent with LSU rDNA sequence analysis of C. virgaureae and Ramularia species. DNA sequences of the type species of both genera, C. virgaureae and R. pusilla, were generated. For the first time a complex cup-shaped appressorium is reported for a member of plant pathogenic cercosporoid hyphomycetes, based on light, scanning and transmission electron microscopy. The appressorium of C. virgaureae is formed by strongly branched hyphae radiating from a supporting intercellular hypha and remaining closely attached to each other. With its concave side the appressorium adheres to a cell of the leaf mesophyll. This structure is significant in comparison with morphologically unspecific intercellular hyphae known in other cercosporoid hyphomycetes. Scanning electron microscopy of conidiogenous loci also provide additional characteristics for distinguishing Cercosporella and Ramularia. Conidiogenous loci are smooth in Cercosporella but similar to the Cladosporium-type (consisting of a circular rim and a central dome) in Ramularia.

A new Chionosphaera species associated with conifer inhabiting bark beetles

An undescribed species of the heterobasidiomycetous genus Chionosphaera is carried by the bark beetles Dryocoetus autographus, Hylurgops palliatus, Ips acuminatus, Ips sexdentatus, Ips typographus, Orthotomicus laricis, Pityogenes chalcographus, Pityokteines spinidens, and Polygraphus poligraphus infesting conifers in Europe (Abies alba, Larix decidua, Picea abies, and Pinus sylvestris). Chionosphaera cuniculicola sp. nov. differs morphologically from C. apobasidialis in the more slender basidiospores. The segregation of the two species is supported by comparison of partial sequences of the large subunit of the ribosomal gene. Isotype material of Chionosphaera lichenicola was re-examined. In contrast to C. cuniculicola and C. apobasidialis, C. lichenicola exhibits clamps at the septa. Fibulostilbum phylacicola is considered as a clamp-bearing species of Chionosphaera.

Phylogenetic relationships and new records of Asterinaceae (Dothideomycetes) from Panama

Asterinaceae are small obligately biotrophic pathogens growing superficially on living leaves of higher plants in tropical and subtropical regions worldwide. The species-rich but rarely studied ascomycete group has an uncertain placement within the Dothideomycetes because molecular data are missing completely up to now. Based on nuclear DNA from fresh material of five Asterina spp. and a related anamorphic stage from Panama, we present the first molecular phylogenetic hypothesis of the Asterinaceae within the Dothideomycetes. A combined SSU and LSU rDNA phylogenetic analysis shows that species of Asterina and its anamorphs form a well supported monophyletic clade within the Dothideomycetes with Venturiaceae as sistergroup. Three Asterina spp. included in the molecular study are new records for Panama and Central America with new records of host plant species: A. cestricola on Cestrum rugulosum (Solanaceae), A. weinmanniae on Weinmannia pinnata (Cunoniaceae) and A. zanthoxyli on Zanthoxylum scheryi (Rutaceae). A. cestricola and A. weinmanniae are illustrated here for the first time.

A new species of Pseudocercospora and new record of Bartheletia paradoxa on leaves of Ginkgo biloba

A new species of Pseudocercospora is described on lesions restricted to the leaf margins of living leaves of Ginkgo biloba in Taiwan. The lesions were also colonized by the hyphomycete Scolecobasidium humicola. Telia of the basidiomycete Bartheletia paradoxa are first recorded from Japan. These three species are presumed to be saprobionts in the primary stage of litter decomposition or as weak pathogens. A short survey of fungi recorded from ginkgo with focus on ginkgo leaves is provided.

Two cheirosporous hyphomycetes reassessed based on morphological and molecular examination

Based on own collections, two species of cheirosporous hyphomycetes (anamorphic Pleosporales) have been reexamined by morphology and molecular analysis. Cheiromyces inflatus is a new record for England. Transfers of Ch. inflatus to Dictyosporium and of Cheiromoniliophora elegans to Pseudodictyosporium are proposed.

Clarifications needed concerning the new Article 59 dealing with pleomorphic fungi

The new rules formulated in Article 59 of the International Code of Nomenclature for algae, fungi, and plants (ICN) will cause numerous, often undesirable, name changes, when only phylogenetically defined clades are named. Our task is to name fungal taxa and not just clades. Two suggestions are made here that may help to alleviate some disadvantages of the new system. (1) Officially an epithet coined in a list-demoted genus that is older than the oldest one available in the list-accepted genus would have to be recombined in the accepted genus. We recommend that individual authors and committees establishing lists of protected names should generally not recombine older epithets from a demoted genus into the accepted genus, when another one from pre-2013 is available in that genus. (2) Because the concepts of correlated teleomorph and anamorph genera are often incongruent, enforced congruence leads to a loss of information. Retaining the most suitable generic name is imperative, even when this is subordinated to another, list-accepted, generic name. Some kind of cryptic dual generic nomenclature is bound to persist. We therefore strongly recommend the retention of binomials in genera where they are most informative. With these recommendations, the upheaval of fungal nomenclature ensuing from the loss of the former Art. 59 can be reduced to an unavoidable minimum.

New species and new records of Meliolaceae from Panama

Three new species of Meliolaceae, Appendiculella monsterae on Monstera deliciosa (Araceae), Asteridiella nitidae on Buddleja nitida (Scrophulariaceae), and Irenopsis chrysophylli on Chrysophyllum sp. (Sapotaceae), are described based on material collected in Panama. Eighteen species of Meliolaceae are reported for the first time for Panama, which include four first records for the Americas, viz. Ast. formosensis, Meliola indica, and M. pisoniae, previously known only from Asia, and M. dissotidis hitherto known only from Africa. Six species of plants are cited as hosts for meliolaceous fungi for the first time. In a phylogenetic hypothesis based on 28S nrDNA sequences, the position of Meliolales, including Appendiculella, Asteridiella, Endomeliola, Irenopsis, and Meliola, is found to be basal to Sordariomycetidae, Hypocreomycetidae, and Xylariomycetidae within Sordariomycetes. The five genera of Meliolaceae form a strongly supported clade. We suggest adopting the concept of the subclass Meliolomycetidae. The monophyly of Asteridiella cannot be confirmed. A hypothetical close relationship between Asteridiella and Appendiculella is not supported, but Endomeliola appears closely related to a species of Asteridiella. Two Meliola species on the same host family are closely related.