Bizarre ‘sea walnut’ creature has ‘anus that only generates when it needs to poop’

A WALNUT shaped jellyfish is thought to be the only creature alive with a disappearing anus.

Biologist Sidney Tamm filmed warty comb jellyfish and discovered that their guts are not permanently open 24 hours a day.

The jellyfish looks a bit like a walnut
Getty – Contributor

The warty comb jellyfish is often referred to as the ‘sea walnut’ and has been observed only creating an anus when it needs to defecate.

Until now, it was widely believed that this kind of jellyfish had a gut that was always open.

The nut like sea creatures eat a diet of small crustaceans and baby fish which they ingest through an opening similar to a mouth.

This food passes down a throat and oesophagus and into a canal shaped stomach which leads to two different canals.

The arrow highlights the bulged area which is a newly opened jellyfish anus excreting waste products

It has long been assumed that the two canals at the end of the warty comb jellyfish gut lead to two different exists but Tamm could not find one no matter how hard he looked.

The biologist then discovered that this was because the jellyfish’s anus completely disappears in between excretions and cannot even be seen with a microscope.

It was also observed that the jellyfish chooses which one of the canals it would like to form an anus at the end of and has never been observed using both.

When the jellyfish needs to relieve itself, one of its gut canals fuses with its skin to form an anal pore.

This anal pore then immediately seals up once all the waste has been excreted.

The jellyfish anal pore open (left) and resealed (right)

This jellyfish anus discovery could now be studied further to teach us about the evolution of permanent animal guts and anuses.

In more animal news, a spider has been spotted attacking a deadly snake in an epic predator battle.

Deadly spiders which were wiped out 110million years ago have been found fossilised underwater with ‘hunting’ eyes that still glow.

Nasa once gave spiders drugs to see how their web-making skills changed while under the influence.

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Source: thesun
Bizarre ‘sea walnut’ creature has ‘anus that only generates when it needs to poop’