Catapults into a deadly trap: The unique prey capture mechanism of Drosera glanduligera

Abstract

Active trapping mechanisms constitute some of the most spectacular examples for how carnivorous plants catch their prey. Recently, we showed that the Pimpernel Sundew (Drosera glanduligera Lehm.) possesses active combined catapult-flypaper- traps which work with a sophisticated two-step mechanism: after mechanical stimulation, elongated marginal snap-tentacles at the trap periphery rapidly fling the prey, often with its dorsal side first, onto sticky glue-tentacles on the leaf blade within less than 1/10 second. Subsequently, stimulated mechanically by the impact, slower glue-tentacles lift the prey into a deeply concave leaf-center where digestion takes place. The snap-tentacles have been analyzed in respect to their kinematics, functional morphology and anatomy, and our observations confirm a complex adaptation to carnivory.