Bob Yirka in Phys.org:
A biologist with the University of Zurich has discovered a species of dragonfly whose females play dead to avoid copulating with other males once her eggs have already been fertilized. In his paper published in the journal Ecology, Rassim Khelifa recalls his first experience with a female mooreland hawker dragonfly playing dead, and what he found after further study of the species.
As Khelifa describes it, he was out collecting larvae in the Swiss Alps one day, when he happened to notice one dragonfly chasing another—suddenly, the one being chased simply stopped flying and crashed to the ground, belly up. The pursuer, he notes, paused for a moment, then moved on. As Khelifa approached the dragonfly on the ground he noted it was female and then was surprised when she suddenly awoke, turned over and flew away.
Intrigued, and suspecting the behavior was intentional, Khelifa initiated a study of the species in their native environment, watching 31 male/female pursuits over time. He reports that the females tried the fake death routine 27 times, and that it worked 21 times. He notes further that in each of the fake death attempts, the female had just left her eggs, or was on her way to tend to them again.
More here. [Thanks to Farrukh Azfar.]