By David Aspinall
This bizarre footage shows other-worldly worms leaving large coils of sand on the sea bed.
While diver Vital Bazarov swam around the Red Sea off the coast of Egypt at the end of September, he spotted perfectly formed piles of sediment forming below him.
Intrigued, the experienced diver swam closer and observed acorn worms burrowed deep under ground excreting the sand they had previously consumed.
The slimy insects suck in the grains, pick out and eat plant and animal material before discharging the filtered sands into the distinctive mounds.
Vital said: “I have spotted these deposits many times but have never seen them being formed.
“These acorn worms live exclusively under the sea bed and push their faeces to the surface.
“The sand that comes out is perfectly clean but wrapped in sand which forms these tubes.”
Acorn worms have round, muscular heads which do the digging with their collars serving as the anchors.
At the junction of these two body parts lies their mouths and when the insects meet something inedible, it ducks under its collar, closing like a plug in a drain.