Pollination mechanism in <i>Serapias</i> with no pollinaria reconfiguration

Abstract Orchidaceae, one of the most numerous families in world's flora, have evolved various pollination strategies to favour cross-pollination, such as deceptive and pollinarium reconfiguration. Among terrestrial orchids Mediterranean, only species belonging genus Serapias show a strategy defined shelter imitation. The floral elements form tubular structure that insects use during their resting phases. purpose this paper was clarify mechanisms guarantee with particular attention morphological interactions between pollinators whether pollinaria reconfiguration is necessary promotion cross-pollination Serapias. Breeding system experiments hand treatments indicated highly self-compatible, shows low value natural fruit set pollinator limited. Time-lapse photos showed had no refolding stipe or caudicle after its removal from flower. morphology flower determined attack on occiput/vertex insect. When insect left flower, unable encounter stigma. made second visit another pollen masses first ended up stigma at same time, picked pollinarium. Our observations analyses suggested are crucial success prevent self-pollination thus unnecessary orchids, species, for crosspollination. represent case plant pollinator; formation shape an essential preadaptation development site mimicry originating exclusively among Mediterranean orchids.