Orthemis sibylla, a junior synonym of O. ambirufa (Odonata: Libellulidae)

Abstract Orthemis sibylla is shown to be a junior synonym of O. ambirufa, based on a comparison of the holotype male of O. ambirufa with voucher specimens in the UMMZ identified as O. sibylla by Ris and specimens of this species from French Guiana and Venezuela in the RWG collection. Diagnostic characters of the male holotype of O. ambirufa are illustrated, and compared with those of O. levis.