Locations of extrafloral nectaries vary from species ot species, but most often they occur on the petiole or rachis near the attachment of the leaf or leaflet bade.
Extrafloral nectaries are also common on the calyx or reproductive axes.
The primary targent of extrafloral nectaries are ants. These plants have evolved in scores of angiosperm families. Most species that have been studied secrete glucose, fructose, and sucrose plus some protein, amino acids, and organic acids. The cells of the extrafloral nectary have densely staining cytoplasm and an inconspicuous vacuole, and the nuclei are large. Characteristically, there are many plasmodesmata connecting these cells through radial and basal cell walls.