Mengual, X. and Thompson, F. C. (2008) “A taxonomic review of the Palpada ruficeps species group, with the description of a new flower fly from Colombia (Diptera: Syrphidae)”, Zootaxa. Auckland, New Zealand, 1741(1), pp. 31–36. doi: 10.11646/zootaxa.1741.1.3.