WATCH: Is it a ghost fish captured on camera underwater?

A diver was surprised to encounter a bizarre fish underwater having a jelly sort of structure with its spinal cord and rib-like features visible from an apparent transparent body.

Raniero Borg, who discovered the bizarre creature near Marsalforn, Malta, said he’d never seen anything like it in 40 years of diving.

He said: ‘It looked like a miniature jelly whale or dolphin.

The video captured underwater shows the diver touching the jelly-like fish with his hand visible from the other side of the creature having a transparent body.

The video also shows the skeleton body of the fish as the diver tries to open its visible mouth to verify if it is a living creature or any other thing.

The 61-year-old diver didn’t know what it was at first. ‘I thought it was a dolphin or whale foetus.’

Now, after consulting contacts at Malta’s International Ocean Institute, he has discovered that what earlier was considered a ghost fish is basically a type of salp he had witnessed underwater.

Salps are often mistaken for jellyfish but are actually taxonomically closer to humans. And they grow remarkably fast – they reach maturity in just 48 hours and can increase their body length by up to 10 per cent per hour.

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They move through the water by contracting bands of muscles that ring their bodies, thereby drawing water in at one end and pushing it out at the other.

They’re filter feeders and not fussy eaters, devouring anything they catch in their feeding net, but their main food is phytoplankton – tiny marine algae.