- Microsporum audouinii
- Microsporum canis
- Microsporum cookei
- Microsporum ferrugineum
- Microsporum gallinae
- Microsporum gypseum
- Microsporum nanum
- Microsporum persicolor
Hyphae septate. Conidiophores scarcely or not differentiated from vegetative hyphae; microconidia (microaleurioconidia) are unicellular, ovoid to club-shaped, and solitary. Macroconidia (macroaleurioconidia) are fusiform, with a thick or thin, echinulate wall, solitary, containing 2 to 15 cells; some species are typically sterile but may sometimes form macroconidia on suitable media.
|Surface:||Texture glabrous, downy, or woolly; white, beige, cinnamon, yellow or rusty on surface.|
|Growth Rate:||Rapid to Slow.|
From a taxonomic point of view, Microsporum is distinguished from Trichophyton and Epidermophyton by its fusiform macroconidia with rough to echinulate walls. In practice, the identification of many species rests primarily on the appearance of the macroconidia, since the microconidia are not sufficiently distinctive to be useful for this purpose. Some species, however, produce few or no macroconidia. The production of macroconidia can sometimes be stimulated by cultivating isolates on lactritmel agar, autoclaved rice grains, Potato Dextrose Agar or Sabouraud Dextrose Agar containing 3 to 5% sodium chloride. In the absence of conidia, the colony appearance and certain physiological tests are used in identification.
Microsporum are cosmopolitan while others have geographically restricted distributions.
Microsporum includes anthrophilic, zoophilic, and geophilic species. Most infections in humans are acquired from infected dogs or cats.
|Microsporum Characteristics of Selected Species|
on rice grains
on rice grains
rare or numerous
at 37 o C.
The genus Microsporum includes some 17 species, of which 5 are primarily isolated from humans and 7 primarily from animals. Microsporum infects the skin and the hair, but seldom infects nails. Microsporum is known to be a causative agent for dermatophytosis, Cutaneous mycoses , Tinea capitis and Tinea corporis (ringworm).
- Inhibitory Mold Agar
- Mycobiotic Agar
- Sabouraud Dextrose Agar
Incubate at 25 degrees C. for 7-14 days.
1. Hensyl, William R., et al. 1990. Stedman's Medical Dictionary , 25th ed. Williams & Wilkins, Baltimore, MD.
2. St. Germain, Guy and Summerbell, Richard, Ph.D. 1996. Identifying Filamentous Fungi , 1st ed. Star Publishing Company, Belmont, CA.
3. Larone, Davise H. 1995. Medically Important Fungi , A Guide to Identification . 3rd ed. American Society for Microbiology Press, Washington, D.C.
4. The Oxoid Vade-Mecum of Microbiology . 1993. Unipath Ltd., Basingstoke, UK.