Trichophyton rubrum

Trichophyton rubrum is a fungus that causes infections in humans, primarily affecting the skin, hair, and nails. It is a common cause of athlete's foot, jock itch, and nail infections. This fungus belongs to the genus Trichophyton, which are collectively known as dermatophytes. These fungi thrive in warm, moist environments and can be transmitted through direct contact or by contact with contaminated surfaces like locker rooms and public showers.12

T. rubrum forms colonies with hyphae, which are transparent, tubelike filaments. These colonies can vary in color, and the reverse side's color can aid in species identification. While other dermatophytes exist, T. rubrum is the most frequently identified cause of athlete's foot.12