Deceptive orchids with Meliponini as pollinators

Visitation of orchids by Meliponini (stingless bees) is confirmed only in 1 3 Melipona, Partamona and Trigona, for Xylobium and Maxillaria, with the ad dition of Trigona fulviventris visiting Ionopsis. Some bees evinced multipl e floral visitation by carrying several stipes and viscidia from pollinaria , thus may cause seed set. None foraged pseudopollen, nor is collection of this substance by bees verified. Meliponine-visited orchids had pollinia in quartets with emplacement on the bee's scutellum, possibly devices for pol linia survival on a social bee passing through its nest. Further, orchids p roduced no nectar, but bees repeatedly came to flowers. A testable basis fo r the orchid-meliponine relationship is mimicry of rewarding resources, or bee pheromone mimicry, recently documented for some honey bees. Meliponine pheromone analogs (nerol and 2-heptanol) are here noted for Maxillaria, but lack of foraging with pheromones by Melipona suggests multiple avenues of mimicry by orchids, including alarm pheromone and carrion mimicry.