Rare 'upside down' jellyfish washes up on Auckland beach

Photo / supplied

An unusual "upside down jellyfish" has washed up on St Helier's Beach following this weekend's wild weather.

Pauline Blackgrove said she was walking on the beach with her son when they spotted the large jellyfish on the shore.

"We've been going there for years and we've never seen jellyfish there," she said.

It was around the same size as her son's size 11 shoe, seen in the photograph she supplied.

Niwa marine biologist Dr Dennis Gordon said the jellyfish was a phyllorhiza punctate.

The species is widespread throughout the world, but not normally seen south of the Hauraki Gulf.

It was not common for the jellyfish to be on St Helier's Beach and the specimen was a "nice size", said Dr Gordon.

They are typically found in warm water and are part of a group of jellyfish known as "upside down jellyfish".

This is because they mostly lie on their backs and have photosynthetic algae in their tentacles, which they use to supplement their food through sunlight.

Beach-goers need not worry about this particular jellyfish, as it was a non-stinging species, he said.