Movie S1.

MRI of a COR-stimulated flytrap. A Dionaea flytrap was stimulated for secretion by application of COR. In the following phases representing Dionaea’s hunting cycle, the trap transiently opens up wider and starts to produce fluid film. After that phase, the trap starts to close slowly, reaching a position similar to mechanically induced fast trap closure. In the final phase, the trap lobes seal hermetically and the emerging external stomach is filled by the digestive fluid.