Heterachthes w-notatum is a species of beetle in the family Cerambycidae. It was described by Linsley in 1935.[1] It is found in Mexico. Under Article 31.2.1 of the International Code of Zoological Nomenclature, the species name must be spelled w-notatum, despite being spelled w-notata by the original author, as letters of the alphabet are neuter in gender.