A form of melanoma occurring most often on the plantar, palmar, subungual, and periungual skin. It presents as a pigmented macular lesion with irregular borders. Morphologically, it consists of atypical spindled and dendritic melanocytes. The epidermis is often hyperplastic and there is pagetoid infiltration of the epidermis by anaplastic cells. The disease is acral lentiginous melanoma (Monarch Disease Ontology id MONDO_0003865). Also known as: acral lentiginous malignant melanoma, acral lentiginous melanoma (disease), acral lentiginous melanoma, malignant, acral lentiginous melanoma, malignant (morphologic abnormality), malignant acral lentiginous melanoma.