In Tasawaq, a Northern Songhay language of Niger, there exists a lexical tone class distinction between stative and active verbs. This tone class distinction only exists in one class of verbs borrowed from Tuareg, verbs with an initial y-. In this article, I argue that the tone class distinction reflects the Tuareg difference between a Short Perfective aspect, used in active contexts, and a Long Perfective aspect, which is mainly found in stative contexts. In Tasawaq, this aspectual distinction has been reinterpreted as a difference in lexical class.