Sandoval-Molina M. A., Zavaleta-Mancera H. A., León-Solano H. J., Solache-Ramos L. T., Jenner B., Morales-Rodríguez S., Patrón-Soberano A., Janczur M. K., First description of extrafloral nectaries in Opuntia robusta (Cactaceae): Anatomy and ultrastructure, PLoS ONE, 2018, 13(7):e0200422, doi: 10.1371/journal.pone.0200422
The first detailed description of extrafloral nectaries in Opuntia robusta, including their development as modified spines, anatomy and secretory cell ultrastructure. It is complemented by observations of ants on young cladodes and changes in nectaries during maturation.