wingspan : male slightly under 60, and female slightly over 60 mm.
F. nessus is fast flying, but not so shy as other Anaea.
it is a common butterfly on the Eastern slopes of the Andes, from Venezuela down to Argentina (Comstock 1961).
we saw it between 1000 and 1700 meters in the 9 de Octubre area, along rio Paute and rio Miriumi and in the Baños/Puyo Corridor.