Physically active carnivorous plants like the venus fly trap are nothing new to science, but what is new is the discovery of an Australian sundew plant that uses quick motion touch-sensitive tentacles to trap unsuspecting prey. The research indicates that carnivorous plants can cover a larger area, and react much quicker than previously thought.
Most ‘mechanical' carnivorous plants use glue-covered tentacles and leaf traps to ensnare insects, but the Drosera glanduligera sundew plant does it with a fast-acting snap action that's never been seen before — and it's able to do so with a highly specialized set of tentacles.
These tentacles, what are called snap tentacles, are triggered when an insect walks around the outskirts of the plant and comes into contact with them. Once activated, the tentacles catapult the insects deeper into the plant where they're ensnared by the glue tentacles. From there, the bug is gradually moved down to the leaf trap, to be digested and assimilated.
The snap tentacles give the plant considerable reach, giving it a distinct advantage when compared to other carnivorous plants. It may also allow the sundew plant to catch larger insects. In addition, they could be catapulting prey towards the center of the plant, which would help it with both digestion and preventing theft by other predators.
You can read the entire study at PLOS.
Image: Poppinga S, Hartmeyer SRH, Seidel R, Masselter T, Hartmeyer I, et al. (2012) Catapulting Tentacles in a Sticky Carnivorous Plant. PLoS ONE 7(9): e45735. doi:10.1371/journal.pone.0045735.