DESCRIPTIONS OF MEDICAL FUNGI

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Descriptions of Medical Fungi
Onychocola canadensis Sigler
Onychocola canadensis is an uncommon cause of distal and lateral subungual or white
superficial onychomycosis. However, it may sometimes be present in an abnormalappearing
nail as an insignificant finding, not acting as a pathogen.
RG-2 organism.
Morphologial Description: Colonies grow slowly and are velvety to lanose, white to
yellowish, with a brownish reverse. Arthroconidia are cylindrical to broadly ellipsoidal,
one to two-celled, hyaline to subhyaline, 4-16 x 2-5 µm in size, forming long chains.
Older cultures may show broad, brown, rough-walled hyphae.
Key Features: Slow growing, white, arthroconidial mould isolated from nails.
References: Sigler and Congly (1990), Sigler et al. (1994), Gupta et al. (1998), de
Hoog et al. (2000, 2015).
a
b
10 µm
Onychocola canadensis (a) culture and (b) arthroconidia.