1 General view of the nesting site of Oxaea austera at Karadya Bioreserve 2 Tumulus and open nest entrance, scale: 1 cm 3 Main shaft 4 Surface texture of the first portion of the shaft showing marks, scale: 0.5 cm 5 Cross section of the shaft showing the discrete wall (arrow), scale: 0.5 cm 6 Curved portion of the main tunnel (left) with a lateral one (right) of nest 1 scale: 1 cm 7 A portion of the lateral tunnel showing the discrete wall (arrow), scale: 0.5 cm 8 The antechamber (arrow) connected to the end of the lateral tunnel, scale: 1 cm.

  Part of: Sarzetti L, Genise J, Sanchez M (2014) Nest architecture of Oxaea austera (Andrenidae, Oxaeinae) and its significance for the interpretation of Uruguayan fossil bee cells. Journal of Hymenoptera Research 39: 59-70. https://doi.org/10.3897/JHR.39.8201