Beachgoers in California have been left shocked after a giant "weird" creature appeared on the shore.

The huge remains of the aquatic animal left swimmers puzzled - before it eventually came to light just what had washed up.

It later emerged that the corpse belonged to a hoodwinker sunfish, or Mola tecta.

The fish measured approximately six feet long and three feet wide and was found at Doran Regional Park in Bodega Bay, just 60 miles north of San Francisco.

The strange-looking fish was only recognised as a species in 2014, and can be distinguished from the more common ocean sunfish due to the lack of head or chin bump.

Marine biologist Marianne Nyegaard, from New Zealand, was the first to identify the fish when it was first discovered.

The fish was approximately six feet long and three feet wide

She confirmed to the East Bay Times that the stranded creature was a hoodwinker, adding: "We know Mola tecta occurs in the Humboldt Current off South America, as far north as Peru.

"But we did not think they would cross the warm equatorial belt - at least not very often.

"But they definitely cross, probably by diving deep and swimming underneath the warmer equatorial surface waters."

Novelist and English Professor at Sonoma State University Stefan Kiesbye was the first to spot the beached fish when he was litter picking early on Sunday morning.

Scientists said it was rare for the fish to pass 'the warm equatorial belt'

He said: "It is sad that it has been washed to shore, but it was so enormous and so weird and gorgeous.

"It is like suddenly you are on another planet."

According to a social media post by Sonoma County Regional Parks, "rangers responded to visitor reports of sharks swimming near the jetty, but the animals were quickly identified as sunfish".

The post added: "Sadly, one of the sunfish didn't survive and is now beached near the jetty.

The hoodwinker sunfish can weigh up to two tonnes

"Rangers have notified local wildlife agencies and nature will now take over, returning nutrients back into the ecosystem.

"As with any animal washed ashore, please do not touch or move the sunfish."

The hoodwinker sunfish is sleeker and slimmer than other Mola species, and can weigh up to two tonnes.