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The global spread of parasitic chytrid skin fungi (Batrachochytrium spp.) is a primary cause of amphibian population declines and extinctions. In Europe, Batrachochytrium salamandrivorans (Bsal) has caused significant declines in fire salamander populations and has yet unpredictable impacts on other European caudate species. The infectious stage of Bsal is an aquatic flagellate zoospore with a diameter of approximately 4.5 µm. Daphnia, a filter-feeding microplankton commonly found in amphibian breeding sites, has been demonstrated to consume zoospores of another chytrid fungus, Batrachochytrium dendrobatidis (Bd). In this study, we investigated the capacity of Daphnia magna to consume and digest Bsal zoospores under controlled laboratory conditions. We applied Nile red-stained and unstained zoospores to Daphnia magna and verified consumption visually and via quantitative polymerase chain reaction. Additionally, the daphnids were subjected to a feeding choice experiment with algae Acutodesmus sp. and Bsal zoospores to determine if the presence of a primary food source affects zoospore uptake. Our results demonstrated that the capability of zoospore uptake could not be disturbed by the presence of algae. These findings suggest that a more comprehensive examination of zooplankton communities and their interactions with and potential to regulate aquatic infectious fungi is required to better understand ecosystems with endangered amphibians adequately.

The debates over the requirement of the International Code of Nomenclature for algae, fungi, and plants(ICNafp) for a viable specimen to represent the name-bearing type material for a species or infraspecific taxon have a long history. Taxonomy of fungi commonly studied as living cultures exemplified by yeasts and moulds, strongly depend on viable reference material. The availability of viable cultures is also particularly useful for several groups of filamentous and dimorphic fungi. While the preservation of metabolically inactive cultures is permitted and recommended by the ICNafp, there is room for improvement. Below, we review the history and current status of cultures as the name-bearing type material under the Code. We also present a roadmap with tasks to be achieved in order to establish a stable nomenclatural system that properly manages taxa typified by viable specimens. Furthermore, we propose setting up rules and defining the nomenclatural status of ex-type cultures under Chapter F, the section of the ICNafp that includes provisions specific to names of fungi.

ABSTRACTThe genus Cerradoa(type species Cerradoa palmaea) was established in 1978 by Hennen and Ono and named after the Brazilian Cerrado biome. The holotype collected in Planaltina, Federal District, Brazil, belonged to the first rust fungus reported on palms (Arecaceae). For decades, the status of Cerradoaas a distinct genus has been regarded as doubtful, representing a synonym of Edythea(Uropyxidaceae) starting with the second edition of the Illustrated Genera of Rust Fungiin 1983. Our molecular phylogenetic analyses, as well as our morphological investigations, allowed us to reject this synonymy, leading to the reinstatement of Cerradoawithin the Pucciniaceae. Cerradoa, together with morphologically similar genera such as the newly established Pseudocerradoawith two species (Ps. paullulaand Ps. rhaphidophorae) infecting araceous hosts, the fern rust Desmella, and also P. engleriana, could not be assigned to any of the seven identified major lineages within the Pucciniaceae. Edythea, instead of being maintained as a member of the Uropyxidaceae, was herein placed in Pucciniaceae, shown phylogenetically in close relationship to Cumminsiella mirabilissima, both infecting the Berberidaceae. Additionally, our extensive phylogenetic analyses add guidance for future taxonomic revisions in the highly polyphyletic genus Pucciniaand other established taxa within the family Pucciniaceae.

With the change to one scientific name for pleomorphic fungi, generic names typified by sexual and asexual morphs have been evaluated to recommend which name to use when two names represent the same genus and thus compete for use. In this paper, generic names in Pucciniomycotinaand Ustilaginomycotinaare evaluated based on their type species to determine which names are synonyms. Twenty-one sets of sexually and asexually typified names in Pucciniomycotinaand eight sets in Ustilaginomycotinawere determined to be congeneric and compete for use. Recommendations are made as to which generic name to use. In most cases the principle of priority is followed. However, eight generic names in the Pucciniomycotina, and none in Ustilaginomycotina, are recommended for protection: Classiculaover Naiadella, Gymnosporangiumover Roestelia, Helicobasidiumover Thanatophytumand Tuberculina, Melampsorellaover Peridermium, Milesinaover Milesia, Phragmidiumover Aregma, Sporobolomycesover Blastodermaand Rhodomyces, and Uromycesover Uredo.In addition, eight new combinations are made: Blastospora juruensis, B. subneurophyla, Cronartium bethelii, C. kurilense, C. sahoanum, C. yamabense, Milesina polypodii, and Prospodium crusculumcombs. nov.

Ustilagois a polyphyletic genus of smut fungi found mainly on Poaceae. The development of a taxonomy that reflects phylogeny requires subdivision of Ustilagointo smaller monophyletic genera. Several separate systematic analyses have determined that Macalpinomyces mackinlayi, M. tubiformis, Tolyposporella pachycarpa, Ustilago bouriquetiiand U. maydis, occupy a unique phylogenetic position within the Ustilaginaceae. A previously introduced monotypic generic name typified by U. maydis, Mycosarcoma, is available to accommodate these species, which resolves one component of polyphyly for Ustilago s. lat. in Ustilaginaceae. An emended description of Mycosarcomais provided to reflect the morphological synapomorphies of this monophyletic group. A specimen of Ustilago maydisthat has had its genome sequenced is designated as a neotype for this species. Taxonomic stability will further be provided by a forthcoming proposal to conserve the name Uredo maydisover Lycoperdon zeae, which has priority by date, in order to preserve the well-known epithet maydis.

The recently described fungal phylum Entorrhizomycotawas established solely for the genus Entorrhiza, species of which cause root-galls in Cyperaceaeand Juncaceae. Talbotiomyces calosporus (incertae sedis)shares morphological characteristics and an ecological niche with species of Entorrhiza. We investigated the higher classification of T. calosporusto determine whether it belongs in Entorrhizomycota. Ribosomal DNA sequences showed Talbotiomyces tobe a close relative of Entorrhizaand both taxa form a highly supported monophyletic group. Based on molecular phylogenetic analyses and in congruence with existing morphological and ecological data, Entorrhizaand Talbotiomycesrepresent a deep dichotomy within the Entorrhizomycota. While species of Entorrhizaare characterised by dolipores and occur on monocotyledons, members of Talbotiomycesare characterised by simple pores and are associated with eudicotyledons. This expands the host range of the recently described Entorrhizomycotafrom Poales toother angiosperms. Higher taxa, namely Talbotiomycet alesord. nov. and Talbotiomycetaceaefam. nov., are proposed here to accommodate Talbotiomyces.

The Amsterdam Declaration on Fungal Nomenclature was agreed at an international symposium convened in Amsterdam on 19–20 April 2011 under the auspices of the International Commission on the Taxonomy of Fungi (ICTF). The purpose of the symposium was to address the issue of whether or how the current system of naming pleomorphic fungi should be maintained or changed now that molecular data are routinely available. The issue is urgent as mycologists currently follow different practices, and no consensus was achieved by a Special Committee appointed in 2005 by the International Botanical Congress to advise on the problem. The Declaration recognizes the need for an orderly transitition to a single-name nomenclatural system for all fungi, and to provide mechanisms to protect names that otherwise then become endangered. That is, meaning that priority should be given to the first described name, except where that is a younger name in general use when the first author to select a name of a pleomorphic monophyletic genus is to be followed, and suggests controversial cases are referred to a body, such as the ICTF, which will report to the Committee for Fungi. If appropriate, the ICTF could be mandated to promote the implementation of the Declaration. In addition, but not forming part of the Declaration, are reports of discussions held during the symposium on the governance of the nomenclature of fungi, and the naming of fungi known only from an environmental nucleic acid sequence in particular. Possible amendments to the Draft BioCode(2011) to allow for the needs of mycologists are suggested for further consideration, and a possible example of how a fungus only known from the environment might be described is presented.

Members of the fungal genus Microbotryum are well-known parasites on eudicotyledonous plant hosts. However, recent studies focused exclusively on Microbotryum species being parasites in the anthers of Caryophyllaceae in which strong host-specificity was confirmed by molecular analyses. Consequently, species numbers have risen considerably as multi-host parasites were split up in so-called cryptic species. We subjected three non-caryophyllaceous Microbotryum groups to molecular phylogenetic analyses to see whether we would confirm multi-host morphospecies or if host-specific cryptic species in these selected groups could be revealed as well (i.e. a group of non-caryophyllaceous anther smuts, parasites on different Fallopia species, and parasites on Polygonum bistorta and Polygonum vi-viparum). We applied a multiple analysis strategy to correct for varying alignment effects on a two-locus dataset (ITS and LSU rDNA). The results obtained by the different approaches are uniform; high host-specificity exists in the non- caryophyllaceous anther smuts, but overlapping host ranges occur in the parasites of Fallopia species. Results for the parasites of Polygonum are similar, with Microbotryum bistortarum being separated into three lineages and M. marginale forming a lineage on P. bistorta which apparently is conspecific with M. bistortarum p.p. Our study shows that phylogenetic patterns within Microbotryum are much more complicated than deduced from morphological observations alone. Even though Microbotryum species are highly host-specific, it is impossible to identify species based solely on host taxa affiliation. Species status is reinstated for the anther smut on Salvia pratensis.

Two new genera, Basidiopycnisand Proceropycnis, and two new species, Basidiopycnis hyalinaand Proceropycnis pinicola, are described. An integrated analysis of morphological, ecological, ultrastructural and molecular data indicates that the new taxa belong to the Atractiellales. Relevant characteristics of the new genera and species are discussed and compared with those of related taxa.

The genus Quambalariaconsists of plant-pathogenic fungi causing disease on leaves and shoots of species of Eucalyptusand its close relative, Corymbia. The phylogenetic relationship of Quambalariaspp., previously classified in genera such as Sporothrixand Ramularia, has never been addressed. It has, however, been suggested that they belong to the basidiomycete orders Exobasidialesor Ustilaginales. The aim of this study was thus to consider the ordinal relationships of Q. eucalyptiand Q. piterekausing ribosomal LSU sequences. Sequence data from the ITS nrDNA were used to determine the phylogenetic relationship of the two Quambalariaspecies together with Fugomyces(= Cerinosterus) cyanescens.In addition to sequence data, the ultrastructure of the septal pores of the species in question was compared. From the LSU sequence data it was concluded that Quambalariaspp. and F. cyanescensform a monophyletic clade in the Microstromatales,an order of the Ustilaginomycetes. Sequences from the ITS region confirmed that Q. piterekaand Q. eucalyptiare distinct species. The ex-type isolate of F. cyanescens, together with another isolate from Eucalyptusin Australia, constitute a third species of Quambalaria, Q. cyanescens(de Hoog & G.A. de Vries) Z.W. de Beer, Begerow & R. Bauer comb. nov. Transmission electron-microscopic studies of the septal pores confirm that all three Quambalariaspp. have dolipores with swollen lips, which differ from other members of the Microstromatales(i.e. the Microstromataceaeand Volvocisporiaceae) that have simple pores with more or less rounded pore lips. Based on their unique ultrastructural features and the monophyly of the three Quambalariaspp. in the Microstromatales, a new family, QuambalariaceaeZ.W. de Beer, Begerow & R. Bauer fam. nov., is described.

Molecular sequence data together with ultrastructural features were used to infer the phylogenetic position of Tuberculinaspecies. Additional ultrastructural characteristics were used to determine their mode of nutrition. We investigated ultrastructural morphology of the type species Tuberculina persicinaand determined base sequences from the D1/ D2 region of the nuclear large-subunit ribosomal DNA of the three commonly distinguished Tuberculinaspecies, T. maxima, T. persicinaand T. sbrozzii.Analyses of sequence data by means of a Bayesian method of phylogenetic inference using a Markov Chain Monte Carlo technique reveal the basidiomycetous nature of Tuberculina.Within the Urediniomycetes, Tuberculinaclusters as a sister group of Helicobasidium,closely related to the rusts (Uredinales). This phylogenetic position is supported by the uredinalean architecture of septal pores in Tuberculina.In addition, we present aspects of the ultrastructural morphology of the cellular interaction of Tuberculinaand rusts showing a unique interaction with large fusion pores, revealing the mycoparasitic nature of Tuberculinaon its close relatives, the rusts.

Tuberculinaspecies are mitosporic parasites of rust fungi. It was demonstrated recently that Tuberculinarepresents the asexual life stage of the plant-parasitic genus Helicobasidium.Here we reveal the host specificities of Tuberculinaand Helicobasidiumspecies on rust fungal hosts by means of infection experiments and molecular analyses. We inoculated species of the rust genera Chrysomyxa, Coleosporium, Cronartium, Gymnosporangium, Puccinia, Tranzscheliaand Uromyceswith conidia and with basidiospores of Helicobasidium longisporumand H. purpureumand with conidia of Tuberculina maxima, T. persicinaand T. sbrozzii.In addition we analyzed base sequences from the nuclear ITS region of 51 Tuberculinaand Helicobasidiumspecimens collected in the field together with the sequences from the Tuberculinainfections obtained by infection experiments. The resulting data show that at least six monophyletic lineages are within the Tuberculina/Helicobasidium-group that can be unambiguously distinguished by combining molecular and morphological characters and by specific host spectra of the Tuberculina-stage. This diversity opens up new vistas on the evolution of this exceptional mycoparasitic-phytoparasitic fungal group.

A new genus, Classicula, and a new species, Classicula fluitans, are described in the Urediniomycetes for the teleomorph of Naiadella fluitans. Classicula fluitansforms transversely septate basidia with subapically swollen sterigmata and long fusiform basidiospores. An integrated analysis of morphological, ultrastructural and molecular data indicates that Classicula fluitansis a member of the Urediniomycetes. Among the Urediniomycetes, Classicula fluitansshares the formation of simple septal pores associated with microbodies and tremelloid haustorial cells only with the hyphomycete Jaculispora submersa. In addition, in our molecular phylogenetic analyses with at least two representatives of all known urediniomycetous groups, Classicula fluitansappears together with Jaculispora submersain a statistically well-supported cluster. Accordingly, the family Classiculaceae and the order Classiculales are proposed to accommodate these fungi in the Urediniomycetes.

A culture was obtained from a spore print of a basidiocarp of Mycogloea nipponicacollected in Taiwan. A yeast stage and basidia identical to those of M. nipponicadeveloped in laboratory media. The Taiwanese specimen of M. nipponicaand its yeast anamorph were characterised in the present study. Comparative morphological, molecular, and ultrastructural studies indicated that the yeast stage can be assigned to the genus Kurtzmanomyces. The revealed connection between the sexual species Mycogloea nipponicaand the asexual genus Kurtzmanomycesdemonstrates the importance of anamorphic characteristics in the modern systematics of heterobasidiomycetous fungi.

Many species formerly listed in Entyloma have been removed and are now placed in several orders. This study aims to clarify the framework of the genus Entyloma and the phylogeny of these plant parasitic smut fungi with molecular data. Analyses of LSU and ITS sequences are presented and support the monophyly of the order Entylomatales. The sequences show higher similarities within the examined species of Entyloma than within other smut families and genera, suggesting a recent radiation. Within the Entylomatales a cluster of anamorphic Tilletiopsis washingtonensis, T. lilacina and T. cremea collections is the sister group to Entyloma. The phylogenetic relationships in the genus Entyloma are a result of joint evolution with their hosts. The analyses of the sequence data show unresolved groups on Ranunculales and a well-supported group on Asteridae.

Phylogenetic analyses of LSU rDNA confirm the association of Lecythophora species with teleomorphs of Coniochaeta. The Lecythophora states described until now, including the type species, L. lignicola, as well as L. hoffmannii, L. mutabilis, L. luteoviridis, L. fasciculata, and L. decumbens, cluster together with Coniochaeta species. In neighbour-joining analysis, the Lecythophora-Coniochaeta group was found to be situated with strong support in a cluster consisting of unitunicate pyrenomycetes. It was not possible to clarify relationships at ordinal level. The Lecythophora states of Coniochaeta ligniaria, C. malacotricha, C. velutina, and C. pulveracea, differing from each other in both morphological and cultural characteristics, were also distinguishable by LSU rDNA analysis, but proved not to be identical with any of the described Lecythophora species. Lecythophora lignicola, L. luteoviridis, and L. fasciculata clustered together with C. velutina, and are therefore regarded as closely related to this species, while L. mutabilis was close to C. ligniaria, and L. decumbens close to C. pulveracea. The tested species of other genera with adelophialides were found to cluster at a relatively great distance from the Lecythophora-Coniochaeta group within the groups of unitunicate pyrenomycetes, as well as the Helotiales, Chaetothyriales, and Dothideales.

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.

Characteristics of hyphal septation, cellular interaction, sporulation, cultures and/or nucleotide sequences from the 5' terminal domain of the nuclear large subunit rRNA gene of some species of Exobasidium, Microstroma and Muribasidiospora were examined and compared. Our analyses show that the order Microstromatales comprises Microstroma, Muribasidiospora triumfetticola and the anamorphic species Rhodotorula bacarum, R. phylloplana and Sympodiomycopsis paphiopedili, whereas Muribasidiospora hesperidium and Muribasidiospora indica are members of the Exobasidiales. Because of the high degree of morphological divergence between Muribasidiospora triumfetticola and Microstroma, a new genus, Volvocisporium, and a new family, Volvocisporiaceae, of the Microstromatales are proposed. Apart from the phylogenetic implications, the most interesting observations in the present work are the unusual development of the basidia, especially of the basidiospores, and the nutrient transport system from the host attacking hyphae to the basidia in Muribasidiospora triumfetticola.

To obtain an understanding of the phylogenetic relationships among the Georgefischeriales, septation, cellular interactions, teliospores, basidia, cultures and nucleotide sequences from the 5' terminal domain of the nuclear large subunit rRNA gene were studied. Analyses of both morphological and molecular characters yield similar phylogenetic conclusions. The Georgefischeriales are divided into three groups, corresponding to the Eballistraceae, Georgefischeriaceae, and Tilletiariaceae. The basal dichotomy is between the Eballistraceae and the branch uniting the Georgefischeriaceae and Tilletiariaceae. The Tilletiariaceae are phragmobasidiate, whereas the Eballistraceae and the Georgefischeriaceae are holobasidiate. The Eballistraceae differ from the Georgefischeriaceae and Tilletiariaceae in the lack of the ballistospore mechanism. The systematic position of Tilletiopsis minor is unclear. The Eballistraceae, Eballistra and Phragmotaenium are proposed as new taxa. The descriptions of the Tilletiariaceae and Jamesdicksonia are emended. Except for Entyloma majus, E. parvum, Georgefischeria, Jamesdicksonia brunkii, J. obesa, Tilletiaria anomala, and Tolyposporella chrysopognis, the teleomorphic species of the Georgefischeriales are presented as new combinations.

ABSTRACTThe similarities of paracoccidioidomycosis and blastomycosis are highly suggestive of a close relation of the two etiological agents. Whereas the agent of the first disease is exclusively endemic in Latin America, the agent of the latter one is endemic in North America and Africa. In symptomatic travelers visiting both areas of endemicity, differentiation of the diseases might be impossible, even though therapy and prognosis for these two diseases differ significantly. In order to identify differences in the 18S rRNA gene (rDNA) for use as molecular diagnostic tools, we sequenced this gene from five isolates of Paracoccidioides brasiliensisand compared them to known sequences of other fungi. Neighbor-joining, maximum parsimony, and maximum likelihood analyses and, finally, the Kishino-Hasegawa test revealed that P. brasiliensis, Blastomyces dermatitidis, and Emmonsia parvaare more closely related than Histoplasma capsulatumand B. dermatitidis, whose teleomorphic forms belong to one genus,Ajellomyces. In accordance with the work of other investigators who have used internal transcribed spacer and large subunit rDNA sequences, our small subunit rDNA data show that the dimorphic fungus P. brasiliensismust be grouped within the order Onygenalesand is closely related to members of the family Onygenaceae. There are hints in the molecular phylogenetic analysis that the family Onygenaceaemight be further divided into two families. The subgroup that includes P. brasiliensiscomprises all zoopathogenic species. The differences in the 18S rDNAs appear to be too small to allow species identification of the members of the family Onygenaceaepathogenic for humans by use of target sequences within this gene.

In order to integrate ustilaginomycetous anamorphs into the general phylogenetic system of Ustilaginomycetes, partial nuclear large subunit ribosomal DNA sequences of 56 teleomorphic and 19 anamorphic species of the Ustilaginomycetes were analysed. Maximum parsimony and neighbour joining confirm the new suprageneric system of Ustilaginomycetes and indicate that (i) the species of Pseudozyma represent anamorphs of Ustilaginales parasitizing grasses, (ii) Pseudozyma prolifica, the type of Pseudozyma, is very closely related to Ustilago maydis, (iii) Pseudozyma tsukubaënsis is probably synonymous with Ustilago spermophora, (iv) the species of Malassezia represent a group of its own within the Exobasidiomycetidae, (v) Tilletiopsis cremea, T. lilacina and T. washingtonensis belong to the Entylomatales and (vi) T. flava, T. fulvescens and T. minor are members of the Georgefischeriales. Like all Tilletiopsis species tested, T. albescens and T. pallescens are members of the Exobasidiomycetidae, but they cannot be ascribed to any of the known orders of this subclass. The description of the Malasseziales is emended.

AbstractA new species of a dimorphic simple-pored auricularioid heterobasidiomycete, Occultifur externus, is described. This fungus was initially isolated in the unicellular stage and identified, on the basis of standard yeast identification tests, as the anamorphic pink yeast Rhodotorula minuta.This yeast was able to complete its life cycle on solid laboratory media. Two yeast cells conjugated, forming mycelium with clamp connections. The same generative hyphae produced clusters of four-celled basidia and characteristic swollen conidiogenic cells that released dikaryotic conidia. Haustorialike structures were formed. Nuclear DNA-DNA hybridization experiments revealed that O. externusis not the teleomorphic stage of R. minutaand molecular sequence data from the large subunit of the rDNA supported the affiliation of O. externusto the Naohidea-Sakaguchiaclade of the Urediniomycetes. Ultrastructural studies revealed the presence of simple septal pores. Cylindrical reticulate bodies were frequently found occluding them. These unique bodies could also be detected in O. internus, which supports the placement of both taxa in the same genus.

AbstractThe genus Cintractias. l. (Ustilaginales, basidiomycetes) comprises about 40 species of smut fungi infecting Cyperaceae and Juncaceae. These organisms form a phenetic continuum with respect to their sets of morphological character states, which do not allow a clear delimitation of infrageneric groups. According to sequence data of the large subunit ribosomal DNA of 17 species of Cintractias. l. and related taxa of other genera of smut fungi, Cintractias. l. is polyphyletic. Five groups of species shown by sequence data are characterized morphologically as different genera: Cintractias. s., Tolyposporium, and the new genera Gymnocintractia, Leucocintractia, and Stegocintractia.Species of Cintractias. s. and Tolyposporiumform one clade, which is supported morphologically by similar soral structure. In the phylogram based on large subunit rDNA sequence data presented here, Cintractias. s. seems to be paraphyletic, but the bootstrap values of this topology are very low and members of Cintractias. s. and Tolyposporiumare morphologically easily distinguishable by the presence of irregularly roughly warty teliospores in balls in species of Tolyposporiumand single, finely warty teliospores in species of Cintractias. s. Species of Gymnocintractiaand those of Leucocintractiaare sister taxa, although the former are similar to species of Stegocintractiaby the absence of a sterile stroma in the sori and foveolate teliospores, and the latter to those of Cintractias. s. by the presence of a sterile stroma, peridia, and nonfoveolate teliospores. Distinctive morphological characteristics were, however, found, such as the presence of fungal peridia in sori of species of Stegocintractiaand their absence in those of species of Gymnocintractia, teliospores with rough warts forming ridges in species of Leucocintractiaand finely warty ones in species of Cintractias. s. Hosts of species of Cintractias. s., Gymnocintractia, and Leucocintractiabelong to the Cyperaceae, those of species of Stegocintractiaand Tolyposporiumto the Juncaceae.

AbstractThe lycophytes represent the most primitive host group for Ustilaginomycetes. Morphology and ultrastructure of the two known smut species on Selaginella, Melanotaenium oreophilumand M. selaginellae, as well as teliospore germination and the 5’ end of the nuclear large subunit rRNA gene of the first species were studied and compared. The results of molecular analyses suggest that these two smut fungi belong either to the Doassansiales or George-fischeriales. The presence of complex interaction apparatus including cytoplasmic compartments favors the placement in the Doassansiales. M. oreophilumand M. selaginellaeshare the type of septal pore apparatus and host-parasite interaction with the Doassansiales, but not with the Georgefischeriales. They differ from the other members of the Doassansiales in the pigmentation of the teliospores and, at least in M. oreophilum, in the basidial type. To accomodate these two species in the Doassansiales, a new genus, Melaniella, and a new family, Melaniellaceae, are proposed. Descriptions and illustrations are given for Melaniella oreophilaand M. selaginellae.

Long-distance transport of mRNAs is crucial in determining spatio-temporal gene expression in eukaryotes. The RNA-binding protein Rrm4 constitutes a key component of microtubule-dependent mRNA transport in filaments of Ustilago maydis. Although a number of potential target mRNAs could be identified, cellular processes that depend on Rrm4-mediated transport remain largely unknown. Here, we used differential proteomics to show that ribosomal, mitochondrial, and cell wall-remodeling proteins, including the bacterial-type endochitinase Cts1, are differentially regulated in rrm4Δ filaments. In vivo UV crosslinking and immunoprecipitation and fluorescence in situ hybridization revealed that cts1 mRNA represents a direct target of Rrm4. Filaments of cts1Δ mutants aggregate in liquid culture suggesting an altered cell surface. In wild type cells Cts1 localizes predominantly at the growth cone, whereas it accumulates at both poles in rrm4Δ filaments. The endochitinase is secreted and associates most likely with the cell wall of filaments. Secretion is drastically impaired in filaments lacking Rrm4 or conventional kinesin Kin1 as well as in filaments with disrupted microtubules. Thus, Rrm4-mediated mRNA transport appears to be essential for efficient export of active Cts1, uncovering a novel molecular link between mRNA transport and the mechanism of secretion.