DESCRIPTIONS OF MEDICAL FUNGI

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Descriptions of Medical Fungi
McGinnis et al. (1986b) have reviewed the isolates from human and animal disease
purported to be Drechslera or Helminthosporium and concluded that all pathogenic
isolates examined actually belong to the genera Bipolaris or Exserohilum.
RG-1 organism.
Drechslera Ito
Morphological Description: Colonies are fast growing, suede-like to downy, brown
to blackish brown with a black reverse. Conidia are pale to dark brown, usually
cylindrical or subcylindrical, straight, smooth-walled, and are formed apically through
a pore (poroconidia) in a sympodially elongating, geniculate conidiophore. Conidia
are transversely septate (phragmoconidia), with the septum delimiting the basal cell
formed first during conidium maturation. Germinating is from any or all cells and the
hilum is not protuberant.
Key Features: Dematiaceous hyphomycete producing sympodial, pale brown,
cylindrical or subcylindrical, transversely septate poroconidia.
References: Luttrell (1978), Ellis (1971, 1976), McGinnis (1980), McGinnis et al.
(1986b), Sivanesan (1987), Rippon (1988), de Hoog et al. (2000, 2015). Also see
Descriptions for Bipolaris, Curvularia and Exserohilum.
20 µm
Drechslera spp. conidia.