MICROSPORUM is a genus of fungi that causes tinea capitis , tinea
corporis , ringworm , and other dermatophytoses (fungal infections of
the skin ).
Microsporum forms both macroconidia (large asexual
reproductive structures) and microconidia (smaller asexual
reproductive structures) on short conidiophores .
hyaline , multiseptate, variable in form, fusiform, spindle-shaped to
obovate, 7–20 by 30–160 um in size, with thin or thick echinulate
to verrucose cell walls. Their shape, size and cell wall features are
important characteristics for species identification.
hyaline, single-celled, pyriform to clavate, smooth-walled, 2.5–3.5
by 4–7 um in size and are not diagnostic for any one species .
The separation of this genus from
Trichophyton is essentially based
on the roughness of the macroconidial cell wall, although in practice
this may sometimes be difficult to observe. Seventeen species of
Microsporum have been described; however, only the more common species
are included in these descriptions.
Microsporum canis var. distortum