Chromoblastomycosis (also known as chromomycosis, cladosporiosis, verrucous dermatitis, phaeosporotrichosis, Pedroso disease, or Fonseca disease) is a subcutaneous fungal infection caused by one of several dematiaceous (pigmented) fungi, most commonly Cladosporium carrionii, Fonsecaea pedrosoi, Fonsecaea compacta, Fonsecaea monophora, Phialophora verrucosa, and Rhinocladiella aquaspersa.

It is typically found on the lower extremities of middle-aged men in rural areas of tropical and subtropical climates. While it is found in most tropical countries, increased reporting has been seen in Madagascar, Australia, China, Mexico, Cuba, and Africa. Twenty percent of cases occur in the temperate climate of Europe or the Americas. Rare reports from Canada and the United States exist.

The fungus is found in soil, plants, and decaying wood. Farmers, agricultural workers, and miners usually acquire it after traumatic penetration during occupational exposure. Working in sandals or barefoot is a major risk factor. Splinters and traumatic penetration are common sources of inoculation, occurring about 1-2 months before development of skin lesions. It is 20 times more common in men than in women due to occupational exposure.

Chromoblastomycosis is a locally progressive disease, usually evolving very slowly over many years without many associated symptoms. Early on, there may be an erythematous papule or a warty plaque. This gradually enlarges if untreated and may become annular, vegetating, or nodular. Lymphatic and cutaneous dissemination have been described. Complications may include lymphedema, elephantiasis, ulceration, and secondary bacterial infection. A rare complication is transformation to squamous cell carcinoma.