A woman was shocked to find a starfish in her bowl of mussels while on a romantic date at a popular London restaurant.

The diner, who did not want to be named, was having lunch with her boyfriend at Belgian restaurant Belgo in King’s Cross on Sunday afternoon when she got to the bottom of a serving of mussels.

Just as she held up the spoon to her mouth she saw something “a little bit odd” in what the restaurant has described as an “extremely rare and unusual situation”.

“I'd almost finished all the mussels and I was eating the soup with my spoon and there were some de-shelled mussels swimming around in it,” she said.

The bowl of mussels came with an unexpected extra

“I spooned one of them up and was moving the spoon to my mouth when I clocked that it looked a little bit odd.

“So I tipped it onto the plate when I realised that what I had thought was a mussel was actually the underside of a little perfectly-formed starfish.

“I'm a bit squeamish anyway so I just thought it was a bit grim to have something unexpected floating around in my food.

“A couple of the mussels had a bit of a crunch, which I thought had been a bit of shell, but now I'm thinking 'oh God, maybe I ate one of his friends'.”

It didn’t seem a big deal to her at first, she said, but her boyfriend, who had also just finished a bowl of mussels, said it was quite worrying.

Mussels should be checked before cooking and shells must be closed beforehand so they are fresh.

The starfish that made its way into the bowl of mussels

The diner said seeing the starfish in her bowl was enough to make her feel queasy, though she does not think eating the food made her sick.

“We mentioned it to the waiter when he came to clear the table but he just said 'oh my God that's amazing, so cool' and walked away,” she added.

“It was literally like the joke – 'don't talk too loudly, everyone will want one'.”

The couple then left without taking it further but Belgo has promised to check its control measures to prevent a repeat ever happening.

A spokesperson from Belgo said: “This is an extremely rare and unusual situation. We source the finest quality, sustainably sourced, fresh mussels and, in this highly unusual occurrence, it would appear a small animal that shares the same habitat has attached itself to a mussel.

“We would like to reassure customers that we are seeking assurances from our suppliers to understand how this anomaly has occurred, and also scrutinising our stringent quality control measures to prevent this happening again.

“We’d like to sincerely thank our guest for bringing this to our attention.”