The two butterflies of the genus Prepona (the other one being Prepona brooksiana diazina) are the most colorful of the Salvadoran Preponas, with the deep purple-blue on the forewing contrasting with the light blue band across both wings in the males.  This is also the most widely distributed of the two, found from sea level to about 1000 m.a.s.l. , which may be due to its food plant being a popular shade tree in coffee plantations.  However, it is never very common.  Flies very fast, and the males especially will come to the faces of people who are perspiring!