Female Preying Mantis eats the male preying mantis after mating….
For a male Chinese mantis (Tenodera sinensis), getting the chance to mate is not always a moment of triumph. Quite the opposite: the act of reproduction leaves the boys teetering on the edge of life or death… and the outcome is all in the hands of their partner. Praying mantis females are notorious for their sexual cannibalism. As such, making the choice to mate with a partner leaves males with a trade-off between reproducing in this particular instance, and having any future possibilities of reproduction eliminated by being devoured by their female friend. Recent research has shown that Chinese mantis males that frequently encounter females will approach with caution and remain a greater distance from their potential mate. However, those that have had restricted access to females, implying a low possibility of future encounters, will exhibit riskier mating behaviours - approaching rapidly and within closer reach. If these females are hungry, you know how the story ends…
Ref: Brown W. D., Muntz G. A. & Ladowski A. J, 2012. Low Mate Encounter Rate Increases Male Risk Taking in a Sexually Cannibalistic Praying Mantis. PLoS ONE 7(4): e35377. [link]