Brown black pigmented nail bands (melanonychia) can be a sign of subungual melanoma. This case report describes a child with melanonychia mimicking melanoma caused by green slime. Presumably, the slime embedded in the Adult and Pediatric Nail Unit Melanoma: Epidemiology, Diagnosis, and Treatment Melanonychia: moles and melanoma on the nail Dr. Podlipnik Pigmented Lesions of the Nail Unit: Clinical and Histopathologic Features