Vélez, D. & Vivallo, F. (2012) A new South American species of Centris (Heterocentris) Cockerell, 1899 with a key to the species with horn-like projections on the clypeus (Hymenoptera: Apidae: Centridini). Zootaxa, 3357 (1), 49–55.
https://doi.org/10.11646/zootaxa.3357.1.4