Throughout lowland Amazonia, tree-dwelling ants collect seeds of several specific plant species and cultivate them in nutrient-rich nests, forming diverse species-specific symbioses known as Neotropical ant-gardens (AGs). In this obligate mutualism, ants depend on their symbiotic plants for nest stability, and plants depend on the ants for substrate and nutrients. AG ants and plants are abundant and dominant members of lowland Amazonian ecosystems, but the cues ants use to locate, recognize and carry their mutualist seeds remain unknown. To characterize behavioral cues on AG seeds, solvent extracts of three species (Anthurium gracile, Codonanthe uleana, and Peperomia macrostachya) were subjected to chromatographic fractionation. To test behavioral activity, each fraction was applied to other seeds that ants ordinarily ignore. At least one fraction of each seed extract elicited retrieval behavior in the AG ant Camponotus femoratus, but the active fractions of the three species differed in chemical composition, indicating that each seed species elicits seed-carrying with a different class of chemical attractants. Volatile attractants of P. macrostachya were further investigated using electroantennography and Y-tube olfactometer bioassays. In the olfactometer, C. femoratus preferred the odor of P. macrostachya seeds over that of control seeds; P. macrostachya extract over solvent blank; and a synthetic blend of electrophysiologically active terpenoid and phenolic P. macrostachya seed components over solvent blanks or a single component. While all AG seed species share a common interaction with ants, the results suggest that each seed species elicits seed-carrying with a different class of chemical cues, and that the seed-collecting behavior involves multiple levels detection, including volatile attractants and contact cues.