Three species of Loasaceae from State of Rio de Janeiro, Brazil, are presented: Loasa parviflora Schrad. is the most frequent species, while L. uleana Urb. & Gilg can be considered as critically endangered, and Caiophora scabra (Miers.) Urb. & Gilg is a new occurrence to the state. A probable isolectotype of L. uleana was located, and the fruit of this species was described and illustrated for the first time.
Loasaceae; taxonomy; phytogeography; Rio de Janeiro
