Erythrasma in darker-skinned individuals often appears as well-defined, reddish-brown or slightly darker patches with fine scaling, usually affecting areas with skin folds such as the armpits, groin, or between the toes. The condition is caused by a bacterial infection from Corynebacterium minutissimum, and while it may be less noticeable on darker skin, it can still cause discomfort and itching. Treatment typically involves topical antibiotics like clindamycin or erythromycin, and maintaining good hygiene to reduce moisture and bacterial buildup in affected areas.