Skin fungus. Coloured scanning electron micrograph (SEM) of the dermatophyte fungus Trichophyton rubrum. The thread-like structures are hyphae, the vegetative part of the fungus. Dermatophyte fungi infect keratinized tissues (skin, nails, hair) in humans and other animals. These fungal infections are known as ringworm, and include the itching and cracked skin of athlete's foot (tinea pedis). Magnification: x1,500 at 6x6cm size. x2400 at 4x4"~SQUARE"