A morphological study of Mexican collections of Crepidotus cinnabarinus, C. croceitinctus, C. palmarum and C. quitensis is provided. The relationships of these species with close allies are examined and discussed. Microscopical observations on the type collections of C. carpaticus, C. cinnabarinus, C. croceitinctus, C. luridus vars luridus, minor and oaxacae, C. macedonicus, C. palmarumm, C. quitensis, C. subcroceitinctus and C. unicus are included. Illustrations of the microscopic features of all taxa are presented.

Most species in Ceratocystiopsis share many characters with species in Ophiostoma. Unlike other Ceratocystiopsis species, C. falcata appears to have enteroblastic conidium development and what appears to be a Chalara anamorph. Morphologically, Cp. falcata is thus more similar to Ceratocystis (with Chalara anamorphs) than Ophiostoma, although it is very distinct from Ceratocystis in perithecial characteristics. Recent studies using molecular data have shown that, despite its peripheral similarity to Ceratocystis, Cp. falcata is distantly related to either Ceratocystis or Ophiostoma. In view of this molecular evidence a new genus, Cornuvesica, is described for it, characterized by having falcate, sheathed and septate ascospores. The anamorph of Cornuvesica is morphologically similar to Chalara but conidia are obovoid with only one truncate end. Conidia are apparently not produced by ring wall building and Chalara is not an appropriate genus for it. We suggest that the anamorph of Cornuvesica represents a genus distinct from Chalara.

A new basidiomycete, Perenniporia nanjenshana sp. nov., found growing saprotrophically on the basal stem of Daphniphyllum pentandrum var. oldhamii in Taiwan, is described and illustrated. It is distinguished from other species of Perenniporia by the resinous to woody basidiomes and large (9.5–14 μm long) ovoid to subglobose, non-truncate basidiospores. Cultural characteristics are described for the species. A key to the world species of Perenniporia with large (> 8 μm long) basidiospores is provided.

The relationship between trichothecene production and pathogenicity was investigated for 29 isolates of Fusarium tumidum, a potential bioherbicide for gorse (Ulex europaeus) and broom (Cytisus scoparius) in New Zealand. All isolates originally derived from broom produced high levels of T-2 tetraol derivatives when grown on ground maize kernels and pearl barley grains, compared with isolates from gorse. Low amounts of scirpentriol derivatives were also produced by both groups of isolates. No nivalenol and deoxynivalenol derivatives were detected in any of the culture extracts. A subset of isolates cultured on gorse and broom tissue produced only small amounts of T-2 tetraol derivatives relative to the amounts produced in grain cultures. Overall, isolates from broom were more aggressive towards both hosts than isolates from gorse, but the pathogenicity of isolates was not correlated with their capacity to produce large amounts of T-2 tetraol derivatives in culture. Two isolates from gorse were highly aggressive towards both weeds. These isolates offer prospects for the development of a safe bioherbicide that could target two major weeds in New Zealand, as trichothecenes were not detected from them at the higher concentrations.

Morels are known to produce ascocarps during a few weeks in the spring. Here we present findings about a Morchella conica population which produces ascocarps during a period of 8–10 months, from early spring until mid-winter. To the best of our knowledge, this phenomenon has not been described previously. Field investigations correlated the ascocarp appearance with gradual drying of the soil. DNA–PCR fingerprinting indicated that these Morchella shared a similar genetic background.

Pseudohelicomyces albus gen. et sp. nov. is described. It is characterised by the presence of hyaline, cylindrical arthroconidia originating from either spiral vegetative hyphae or from spiral, branched conidiophores. The hyphae and conidiophores may or may not possess clamp connections. The characteristics of the basidiocarps formed in culture were identical to material collected from nature. P. albus is the anamorphic stage of Psilocybe merdaria and shows similarities to Helicomyces.

A new genus, Halorosellinia, is introduced to accommodate the lignicolous mangrove inhabitant Hypoxylon oceanicum. A detailed illustrated account of the teleomorphic and anamorphic states is given. Halorosellinia oceanica comb. nov., is compared with Stilbohypoxylon quisquiliarum and Nemania confluens (a reduced form of Nemania) and the reasons for introducing a new genus are discussed. Data on the ecology and geographical distribution of H. oceanica are presented.

Beltraniopsis miconiae sp. nov. was isolated on decaying leaves of Miconia cabussu and characterized by the constriction at the subequatorial zone of the conidium and inflated apical cell of the setiform conidiophore. It is described and illustrated and a key to the known Beltraniopsis species is provided.

Two new species of Unguiculariopsis are described from tropical Guangxi and the Changbai Mountains in northeastern China. Unguiculariopsis changbaiensis and its anamorph Deltosperma oblongum occurs on a pyrenomycete and U. damingshanica is lichenicolous.

Bulbocatenospora complanata gen. et sp. nov. is described and illustrated. The fungus is characterized by the production of inconspicuous, brown conidiophores, usually reduced to the conidiogenous cells, which are monotretic, ventricose, dark brown, with a well-defined pore. The conidia are muriform, broadly ovoid to irregular, complanate, brown, forming short, acropetal chains. The fungus was found on rotten leaves of Bactris setulosa in an undisturbed rainforest in Venezuela. Comparisons are made with some morphologically similar genera, Piricauda, Chuppia and Janetia.

Developmental stages in mitospore production in Pseudocercospora musae were examined by differential interference contrast light microscopy, scanning electron microscopy, and transmission electron microscopy. Mitosporogenous cells consistently originated directly from upper stromatic cells. Concentric bodies were found in both stromatic and mitosporogenous cells. The cell wall of stromatic cells, mitosporogenous cells, and mitospores, consisted of two layers. Mitospore ontogeny was found to be holoblastic and mitospore secession schizolytic. After liberation, the mitosporogenous cell apex and the mitospore base exhibited a half septum consisting of one layer. A central pore, occluded by a Woronin body, was observed in the mitosporogenous locus. Mitosporogenous cells proliferated percurrently. The morphological characteristics of the apex of mitosporogenous cells and the base of liberated mitospores in P. musae is of fundamental value in defining unthickened scars as important criteria for generic separation within the Cercospora-like generic assemblage.

The majority of microbes living on forest trees are still unnamed and our knowledge of their species richness is vague. This paper describes the fungal diversity of the above ground parts of a 61 year old Norway spruce tree lacking visible signs of damage or disease. The problem involved with identification of the fungi to named species was circumvented by classifying them into operational chemotaxonomic units (OCTUs) by using their combined fatty acid and sterol profiles (FAST-profiles). The variation of these units was chosen to correspond to a within-species-variation determined for several morphologically defined taxonomic species occurring on Norway spruce. Ninety-nine OCTUs were identified from 666 fungal isolates obtained. Bacteria were found only occasionally from the inner bark samples (three isolates) and from needles (five isolates). Models describing the accumulation of OCTUs against the number of samples taken were used for extrapolation of the total number of fungal OCTUs in the above ground parts of the tree. Our results suggest that an undamaged, apparently healthy Norway spruce, harbours in its above ground parts nearly two hundred fungal species. The majority were estimated to be needle epiphytes. At the large forest area scale, the species richness may be one order of magnitude higher.

We report the ability of Conidiobolus adiaeretus to form repetitional microconidia and capilliconidia. Detailed descriptions of development and germination are given. This is the first report of any entomophthoralean fungus producing both these alternative conidial types. This cuts across current definitions of subgenera in Conidiobolus which are based on the absence of these conidial types or on the presence of either microconidia or capilliconidia but not both. Co-occurrence of both these spore types, along with the unusual mode of formation of the microconidia, and the ability to derive capilliconidia directly from the latter, reinforce other features which set C. adiaeretus apart. Taxonomic, evolutionary and ecological implications are briefly discussed.

Torrentispora fibrosa gen. sp. nov. (Ascomycota, Annulatascaceae) is described based on specimens from submerged wood collected from streams in Tai Po Kau Forest Reserve, Hong Kong. T. fibrosa is characterized by immersed to superficial ascomata with a peridium of black cells arranged in irregular rows, wide septate paraphyses, long cylindrical asci with a relatively massive refractive apical ring, and unicellular ascospores with a fibrillar sheath. Illustrations from light and scanning electron microscopy are provided. It is compared with species in the genus Annulatascus, from which it differs in ascoma peridium and ascospore sheath morphology, and with other aquatic ascomycetes possessing ascospores with a similar fibrillar sheath structure.

Three new thermotolerant species of Corynascus isolated from Indian and Argentinian soils are described and illustrated: C. sexualis sp. nov. characterised by small ascospores and the absence of a Myceliophthora anamorph (present in all other species of the genus); C. similis sp. nov. characterised by navicular ascospores with two lateral to sub-terminal germ pores; and C. verrucosus sp. nov. distinguished by the ellipsoid ascospores with two oblique to sub-terminal germ pores. A study to compare the ITS-region sequences of all species of the genus with representative species of related genera demonstrated that this region is very conserved in this group of fungi and of low taxonomic value. A key to the eight species of the genus now known is provided. The molecular data suggest the genus is best placed in the Chaetomiaceae rather than the Ceratostomataceae.

Three Harknessia species are reported on eucalypt leaves from Tasmania, Australia. Harknessia hawaiiensis is a new record for Australia and H. victoriae for Tasmania. Harknessia tasmaniensis is described and illustrated as a new species.

The morphology of Botryobasidium musaisporum sp. nov., a species with bananiform basidiospores collected in Taiwan, is illustrated, described, and discussed. Only one other Botryobasidium with bananiform basidiospores is known, B. bananisporum described from Africa. A key to 13 Taiwanese Botryobasidium species is provided.

On the basis of all accessible records from the literature and our own field observations and collections, the ecology of the rare myxomycete Barbeyella minutissima is described. Analysis of these data, derived mainly from the Northern Ammergauer Alps (Germany) and the Appalachian Mountains (USA: West Virginia, North Carolina), permit the microhabitat requirements of this myxomycete and its ecological associations with other myxomycetes and bryophytes to be elucidated in some detail. Barbeyella minutissima appears to have a distribution centred in montane spruce-fir forests, where it is regularly associated with three other species of myxomycetes – Colloderma oculatum, Lamproderma columbinum, and Lepidoderma tigrinum. Several leafy liverworts are associated with Barbeyella. Particularly noteworthy is Nowellia curvifolia, which seems to be an indicator organism for this myxomycete. A world distribution map of Barbeyella minutissima is provided, along with conclusions relating to the putative range of the species.

A new aero-aquatic helicosporous hyphomycete, Helicodendron microsporum, is described and illustrated from decaying leaves submerged in a small artificial pond surrounded by Quercus ilex and Pinus halepensis in Mallorca, Spain. It is characterized by branched conidiophores with chains of hyaline conidia eventually forming white clusters which do not break up even at maturity. It also has small conidia (8–10 μm diam.) consisting of a 2–2.5 μm thick filament which coils 1.5–2 times counter-clockwise. The main characters of the species are compared with 14 similar hyalosporous Helicodendron species.