A new species of Pareuptychia Forster, 1964, P. milleri n. sp. , is described based on male specimens from the northwestern Amazon basin. Male specimens can be distinguished from other Pareuptychia species by the reduced white dorsal wing markings and darker ventral wing coloration. Two male genitalia characters are identified as likely synapomorphies for Pareuptychia . Morphological characters including male genitalia are illustrated and a distribution map is provided. The female of P. milleri n. sp. is unknown.