Some dematiaceous hyphomycetes from branches and phyllodes on Acacia in Australia

Abstract

Four dematiaceous hyphomycetes associated with grey colonies on stems and branches and 1 species associated with necrotic phyllode lesions of Acacia spp. are described and illustrated. Corynespora alternarioides on stems of A. mitchellii differs from previously described species in having muriform obpyriform conidia and non-proliferating conidiogenous cells. Corynespora queenslandica is associated with distinct lesions on phyllodes of A. leiocalyx, A. concurrens and A. aulacocarpa and again has non-proliferating conidiogenous cells but long filiform conidia. Sporidesmium corrugatescens on stems of A. dealbata combines micronematous conidiophores and distoseptate verrucose conidia. Janetia refugia on stems of A. elata has finely verruculose distoseptate conidia, the basal cell of which is darker and protuberant, and short conidiogenous cells which are more deeply pigmented towards the apices, while J. canescens on stems of A. fimbriata and A. linifolia has polyblastic conidiogenous cells and pyriform to cylindrical conidia in which the base is more darkly pigmented and the walls are distinctly invaginated at the distosepta.