What type of lesions are characteristic of infective endocarditis and are usually painless and erythematous?

Janeway lesions are characteristic of infective endocarditis and are known to be painless, erythematous macules that usually appear on the palms and soles. These lesions are a result of septic emboli leading to small infarcts in the skin, and their presence is associated with a systemic infection involving the heart valves.

In contrast, Osler's nodes, another type of skin manifestation associated with infective endocarditis, are painful and raised, typically occurring on the fingers or toes. This distinction between the characteristics of Janeway lesions and Osler's nodes is crucial for recognition in a clinical context.

Keratoacanthomas are skin tumors that often present as dome-shaped nodules and are not associated with infective endocarditis. Similarly, nodular melanoma is a type of skin cancer that can present as a darkly pigmented lesion and is unrelated to the infectious process of endocarditis. Therefore, the defining features of Janeway lesions make them the correct answer in identifying the painless and erythematous skin lesions associated with infective endocarditis.