Tinea is caused by dermatophytes, a group of fungi that thrive on keratinized tissues. The primary genera responsible are Trichophyton, Microsporum, and Epidermophyton. These fungi are adapted to colonize skin, nails, and hair, leading to various tinea forms such as tinea pedis (athleteâs foot), tinea corporis (body ringworm), and tinea capitis (scalp ringworm).