DESCRIPTIONS OF MEDICAL FUNGI

Descriptions of Medical Fungi 149
Synonymy: Microsporum cookei Ajello; Microsporum racemosum Borelli.
Lophophyton cookei is a geophilic fungus which has been isolated from the hair of
small mammals showing no clinical lesions. Infection has been reported in rodents,
dogs and rarely in humans. It is not known to invade hair in vivo, but produces hair
perforations in vitro. RG-1 organism.
Morphological Description: Colonies are flat, spreading, buff to pale brown, powdery
to suede-like, with a slightly raised and folded centre and some radial grooves. Reverse
pigment dark reddish-brown. Numerous large, very thick-walled, echinulate (rough)
elliptical macroconidia with predominantly five to six septa but may be from two to eight
septa. Occasional spiral hyphae may be seen. Moderate numbers of mainly slender
clavate with some pyriform microconidia are present.
Key Features: The macroconidia of L. cookei are quite characteristic and diagnostic;
the thick walls and usually larger size of the macroconidia distinguish it from N. gypsea.
Confirmatory Tests:
Paraphyton cookei (Ajello) Gräser & de Hoog
Vitamin Free Agar (Trichophyton Agar No.1): Good growth indicating no special
nutritional requirements, pinkish-buff-coloured, suede-like colony with a deep magenta
red reverse.
Hair Perforation Test: Positive.
Key Features: Distinctive macroconidial morphology and culture characteristics.
Molecular Identification: ITS sequencing is recommended.
References: Rebell and Taplin (1970), Rippon (1988), Gräser et al. (2008), Cafarchia
et al. (2013), de Hoog et al. (2015, 2016).
a
b
20 µm
Lophophyton cookei (a) culture and (b) macroconidia.