Vivallo, F., and F. C. V. Zanella. “A New Species of Centris (Paracentris) Cameron, 1903 from Northeastern Brazil, With a Key for the Centris Species of the Caatinga Region (Hymenoptera: Apidae)”. Zootaxa, vol. 3298, no. 1, May 2012, pp. 1–16, doi:10.11646/zootaxa.3298.1.1.