Asia-Tropical: Maluku (Maluku present); Philippines (Philippines present), Luzon present, Mindanao present, N. Celebes present, Obi Island present, Samar present
Malesia: Philippines (Luzon, Samar, Mindanao), Moluccas (Obi Island), N. Celebes?
The hairs on the lower surface of pinnae are inconstant. I am not sure of a clear distinction between this species and A. ceramicum. A specimen collected by H. H. Bartlett (n. 7693) from Asahan, Sumatra has hairs on the lower surface as in the type of A. attenuatum, but glands are not well preserved. Endert 4165 from E. Kalimantan is similar.