Is the mystery creature found in a British can of tuna a tongue-eating louse?

A surprise face in a can of tuna could be a tongue-eating louse, according to an expert.

British mother Zoe Butler, 28, tweeted photos of a "grim" discovery she made inside a can of Princes tuna chunks back in January, but the images have gone viral this week.

At first, it appeared to only be the head of a juvenile crab.

Now, according to The Telegraph, it may be something much worse.

"From what I can see I would support the head of a tongue-eating louse, Cymothoa exigua or similar," said Stuart Hine, Identification and Advisory Service manager at the Natural History Museum in London.

Hine added that the lice are "associates of smaller fish than tuna and fish that tuna eat."

Above is a photo of tongue-eating louse from Flickr. What do you think?

The tuna company is investigating the matter.