An Israeli researcher holds a sea squirt in the Red Sea
An Israeli researcher holds a sea squirt in the Red SeaReuters

A Tasmanian woman suffered numbness after touching an aquatic animal which looks like a human brain.

The woman encountered several of the creatures at the beach and went to the Field Naturalists of Tasmania Facebook page to inquire as to what they were.

"Can someone tell me what this is? Me and my mother kept seeing them on the beach and when I touched it I went numb," she wrote.

"It's slimy but hard what kind of sea creature is it?" she asked.

"I touched it with my finger it went numb. Mum accidentally touched one with her foot and went numb in her foot."

Dr Simon Grove, a curator of invertebrate zoology at Tasmanian Museum and Art Gallery, answered: 'It's a colonial sea-squirt, aka ascidian. Possibly the widespread but non-native Botryllus schlosseri."

Other social media users joked that the creature was someone's missing brain.

Ascidians are a class of invertebrate filter feeders which typically grow in colonies on solid surfaces such as rocks and even other animals. The colonies are made up of zooids, smaller animals that are part of a larger colonial animal and are connected by blood vessels.

Botryllus schlosseri is known as the golden star tunicate because colonies often grow in the shape of stars. The species has a widespread distribution and has been known to cause significant damage to marine habitats and biodiversity.