A new species of Maranta from the Brazilian Atlantic Forest is described. The new species is most similar to Maranta ruiziana, from which it differs mainly in its bambusoid habit, non starch‐storing rhizome, homotropic leaves, with blade entirely glabrous on both surfaces and leaf margins entire, florescence components with numerous cymules, sepals longer than the corolla tube, and spheroidal fruit. The new species also presents morphological characters seen in Maranta tuberculata, from which is easily distinguished by its fruits. I characterize the new species by its external morphology, provide a distribution map, and perform a preliminary conservation assessment based on the IUCN criteria.