A video has emerged from the US of what's believed to be a female praying mantis biting the head off its male mate.

The footage, filmed at the beginning of September in Maryland, US, shows the mantis consuming its partner.

The last shot of the video shows what's left of the victim mantis after the female's feast - only half its body.

Praying mantises are renowned for their cannibalistic behaviour as they will eat just about any insect they can get their hands on, including their own species.