DESCRIPTIONS OF MEDICAL FUNGI

Descriptions of Medical Fungi 5
Aphanoascus fulvescens is a soil-borne keratinolytic ascomycete that occasionally
causes dermatomycosis in humans and animals.
RG-2 organism.
Aphanoascus fulvescens (Cooke) Apinis
Morphological Description: Colonies are moderately fast growing, white to tan with
the production of numerous spherical, pseudoparenchymatous, buff to light brown
cleistothecia (non-ostiolate ascocarps). Asci are subspherical to ellipsoidal and eightspored.
Ascospores light brown, yellowish to pale brown in mass, irregularly reticulate,
lens-shaped, 3.5-4.7 x 2.5-3.5 µm. Aphanoascus fulvescens has a Chrysosporium
anamorph showing typical pyriform to clavate-shaped conidia with truncated bases,
15-17.5 x 3.7-6 µm, which are formed either intercalary, laterally or terminally.
Molecular Identification: ITS sequencing will differentiate most species. The
calmodulin gene may also be useful (Cano et al. 2002, Halliday et al. 2015).
Key Features: Keratinolytic, cleistothecia, and a Chrysosporium anamorph.
References: Domsch et al. (2007), McGinnis (1980), de Hoog et al. (2000, 2015),
Cano and Guarro (1990), Cano et al. (2002).
a
b
100 μm
c
10 μm
Aphanoascus flavescens (a) culture, (b) cleistothecium and (c) conidia.