Fungus
Fonsecaea (chromoblastomycosis)
Dematiaceous mold; copper-penny sclerotic bodies
fon-se-SEE-uh
High-yield clue
Copper-penny 'muriform (sclerotic) bodies' in tissue with a warty/cauliflower-like verrucous skin plaque is the core study clue.
Overview
A melanized (dematiaceous) mold, chiefly Fonsecaea pedrosoi, that causes chromoblastomycosis, a chronic subcutaneous infection after traumatic implantation in tropical rural workers. Classic pigmented-fungus teaching organism defined by muriform cells in tissue.
Classification
- Dematiaceous (melanized) mold
- Ascomycota
- Forms muriform/sclerotic bodies in tissue
- Fonsecaea pedrosoi principal agent
- Environmental soil/plant saprophyte
Lab & identification clues
- Copper-penny muriform (sclerotic) bodies microscopy vocabulary
- Melanized (brown-pigmented) hyphae distinction
- Multiplanar-dividing thick-walled cells in tissue vocabulary
- KOH/histology of verrucous lesion scrapings vocabulary
Associations
- Chronic verrucous cauliflower-like skin plaques vocabulary
- Traumatic implantation in barefoot rural workers
- Tropical and subtropical geographic distribution
- Slow lymphatic and local spread teaching point
Commonly confused with
- Sporothrix schenckii (subcutaneous implantation mycosis)
- Phaeohyphomycosis (dematiaceous tissue hyphae, not sclerotic bodies)
Your notes
Original student-study summary. Sources checked: OpenStax Microbiology 2e, NCBI Bookshelf Medical Microbiology, and CDC topic pages where applicable; reviewed 2026-06. Educational only; no diagnosis, treatment, dosing, or specimen-handling guidance.