Marcetia is a genus of flowering plants belonging to the family Melastomataceae. Its native range is Southern Tropical America. It is found in Brazil, Colombia, Guyana and Venezuela. The genus name of Marcetia is in honour of François Marcet (1803–1883), a Swiss doctor, physiologist, inventor, and professor of physics. It was first described and published in Prodr. Vol.3 on page 124 in 1828.