Pigmented Nail Lesions: When to Observe, When to Biopsy, When to Widely Excise, and When to Amputate? Journal of Hand Surgery Melanonychia: moles and melanoma on the nail Dr. Podlipnik Subungual Melanoma IntechOpen 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 Pigmented Lesions of the Nail Unit: Clinical and Histopathologic Features Pigmented Nail Disorders Basicmedical Key