And just when the crab thought it was safe to crawl out from under its rock…

A video has been released showing the moment an unwitting crab was captured and devoured by a lightning fast octopus in Western Australia.

The video was taken by an amateur nature photographer Porsche Indrisie in Yallingup in Western Australia and shows the speedy predator launch itself from under a rock at the crab before wrapping it in its deadly tentacles. Hardly able to contain her excitement, Indrisie can be heard shouting to a friend, “Hey, it’s an octopus eating a crab!” as the cephalopod awkwardly crawls across the rock and back into the water, dragging its prey with it.

Writing under the video, Indrisie said: “I didn't know why I chose to film this crab, but thought I would try and get closer to it - but something else beat me to it.”

“We hung around for a while, but I understand octopus flip it open and eat it pretty quick, so I knew it was toast.”

Despite octopuses being known as sea creatures, it is not uncommon for them to be seen on dry land while searching for prey.