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Chocolate Spot leaf disease of Eucalyptus is associated with several Heteroconium-like species of hyphomycetes that resemble Heteroconium s.str. in morphology. They differ, however, in their ecology, with the former being plant pathogenic, while Heteroconium s.str. is a genus of sooty moulds. Results of molecular analyses, inferred from DNA sequences of the large subunit (LSU) and internal transcribed spacers (ITS) region of nrDNA, delineated four Heteroconium-like species on Eucalyptus, namely H. eucalypti, H. kleinziense, Alysidiella parasitica, and one isolate resembling a novel species in a clade separate from the holotype of Heteroconium, H. citharexyli. Based on molecular phylogeny, morphology and ecology, the Heteroconium-like species associated with Chocolate Spot disease are reclassified in the genus Alysidiella, which is shown to have mycelium that is immersed in and superficial on the host tissue and conidiogenous cells that can have loci that are either inconspicuous or proliferating percurrently. Furthermore, conidiogenous cells can either occur solitary on hyphae, or be sporodochial, arranged on a weakly developed stroma, which further distinguishes Alysidiella from Heteroconium. [ABSTRACT FROM AUTHOR]

Morphological and molecular studies led to the description of Heteroconium triticicola as a new species isolated from roots of wheat in the United Kingdom. The new fungus shares with H. citharexyli, the type species of Heteroconium Petrak, features such as superficial mycelium, macronematous, mononematous, unbranched, straight conidiophores, monoblastic, integrated, terminal, cylindrical conidiogenous cells, and catenate, dry, simple, cylindrical, obclavate, often pale brown, smooth, multiseptate conidia. The genus Heteroconium is proposed as an anamorph within Hyaloscyphaceae. [ABSTRACT FROM AUTHOR]

Torula glutinosa, a sooty mold on living leaves and stems of Eriodictyon spp. from California is illustrated and described. It shares, with the type species of Heteroconium, H. citharexyli, acropetal conidiogenesis of chains of conidia of variable length and acropetal transseptation. An unnamed synanamorph is recognized and described. [ABSTRACT FROM AUTHOR]