Oil rewarding flowers: Heteropterys intermedia (A. Juss) Griseb. and Heteropterys argyrophaea A. Juss. Other resources (nectar/pollen): Stachytarpheta cayennensis (Rich.) Vahl (Torretta & Roig-Alsina, 2016; Torretta et al. 2022)
References
TORRETTA, J. P. & ROIG-ALSINA, A. 2016. First report of Monoeca in Argentina, with description of two new species (Hymenoptera: Apidae). J. Melittology 59: 1-12
TORRETTA, J.P., ALISCIONI, S. S., MARRERO, H.J., AVALOS, A. A. 2022. Oil flowers of Malpighiaceae and its oil-collecting bees: loyalty and robbery in a highly specialized system. Apidologie 53: 30