Monographs Details: Arrabidaea nigrescens Sandwith
Authority: Maguire, Bassett. 1978. The botany of the Guayana Highland--part X. Mem. New York Bot. Gard. 29: 1-288.
Discussion:5. Arrabidaea nigrescens Sandwith, Lloydia 2: 209. 1939.
Type. Guyana: Akarai Mountains, Smith 2977 (F, GH, K, MO, NY, P, US).
The type of this primarily lowland species is from Guyana but it is not common in the Guayana region. However it is abundant in Amazonian Brazil. Its dendroid tomentum and prominendy veined leaflets are important characteristics.