Final answer:
Tinea versicolor is characterized by discolored patches on the skin caused by yeast overgrowth, while tinea corporis (ringworm) presents as a red ring. Ringworm can be diagnosed with a Wood's lamp and culturing, differentiating it from tinea versicolor.
Step-by-step explanation:
The characteristic feature of tinea versicolor is the presence of patches on the skin that may be lighter or darker than the surrounding skin. The affected areas might not tan in the sun and can be flaky or scaly. Tinea versicolor is caused by an overgrowth of a type of yeast that naturally lives on the skin. This condition is different from tinea corporis, commonly referred to as ringworm, which presents as a red ring on the skin caused by a different type of fungus. However, both are types of superficial mycoses. Tinea corporis produces lesions that grow radially and heal towards the center, which leads to the characteristic appearance of a ring.
Positive identification of tinea infections, such as tinea corporis, typically requires culturing. For instance, Sabouraud's agar may be used to culture the fungi responsible for ringworm, which often turns out to be Trichophyton rubrum. A Wood's lamp can be used to diagnose conditions like ringworm, as it causes the fungal elements to fluoresce. In contrast, the diagnosis of tinea versicolor often involves visual inspection and can sometimes be supported by skin scrapings examined under a microscope.