This is a praying mantis (mante réligeuse). Its name comes from the fact that it looks like it is praying while waiting to catch other insects to eat. This little creature is far from religious or pious, though, it devours other insects, and the females are know to kill and eat the males after mating! They abandon their eggs, leaving the baby mantids to look after themselves.
My daughter and I once caught a praying mantis and kept it for several months at home. I had to catch flies every day to feed it.
With this insect we have an interesting play on words (jeu de mots), because here ‘pray’ is ‘prier’ because of its praying position. But we have a homophone (pronounced the same way) ‘prey’ which means ‘chasser’ in French.