Male terminalia of E. engeli (paratype, KUNHM-ENT 0504531). 106 Seventh metasomal sternum in ventral view 107, 108 Eighth metasomal sternum in ventral and lateral views 109–111 Genital capsule in dorsal, ventral, and lateral views.

  Part of: Gonzalez VH, Griswold T, Simões M (2017) On the identity of the adventive species of Eufriesea Cockerell in the USA: systematics and potential distribution of the coerulescens species group (Hymenoptera, Apidae). Journal of Hymenoptera Research 55: 55-102.