Pearl Bodies of a Neotropical Tree, Ochroma Pyramidale: Ecological Implications

Multicellular, spherical or club‐shaped pearl bodies characterized by large intracellular lipid vesicles are produced on leaves and stems of juvenile Ochroma pyramidale , a tree of second growth vegetation in lowland wet forest of the neotropics. Several lines of evidence suggest that pearl bodies are linked to maintenance of foraging ants on the plant: (1) their production is closely associated with foliar nectar secretion; (2) they are abundant on saplings grown in the glasshouse (averaging 402 bodies leaf –1 ) but were not observed in the field where ants are predictably associated with Ochroma samplings; (3) pearl bodies are energy‐ and lipid‐rich averaging 27.80 kJ/g dry wt –1 and 74.4% lipid; (4) they are constricted at the base and easily detach from the leaf; (5) four ant species collect pearl bodies from artificial depots and return them to their nests. Chelaner sp. detaches pearl bodies from the leaf and returns them to the nest. Production of pearl bodies represents about 25% of the energy allocated to foliar nectar by saplings. Characteristics of the pearl bodies of Ochroma are consistent with those of a widespread group of trichomes and leaf emergences suggesting a common ecological role as ant food for these structures.