We report a case of onychomycosis caused by Scytalidium dimidiatum (sy
n., Hendersonula toruloidea) in a patient who did not live in an endem
ic area. This nondermatophyte mold may produce disease indistinguishab
le from dermatophyte fungi, but it does not respond to current systemi
c antimycotic therapy. Distal subungual onychomycosis, lateral onychol
ysis followed by lateral nail plate invasion, and chronic paronychia a
re common nail presentations.