A lateral gynandromorph of Thyreus redactulus? Cockerell is described and figured, with a particular emphasis on the genitalic sclerites. As such, the sting morphology and mechanism are described for T. ramosus (Lepeletier de Saint Fargeau) to provide a comparative framework for understanding the gynandromorph. The implications of the gynandromorph's genitalic arrangements for intersexual homologies are explored.