Like the hell-raising rocker it is named after, the creature was no shrinking violet.
At 19ft (5.8m) long, with a skull measuring just over a metre, it used its large, blunt teeth to crush bones and turtle shells.
It would have been one of the biggest coastal predators of its time when it roamed the Earth more than 145 million years ago.
It has now been named Lemmysuchus, which translates as “Lemmy’s crocodile”.
It comes after a study of a fossil skeleton housed at London’s Natural History Museum, which was dug up from a clay pit near Peterborough in 1909, by University of Edinburgh palaeontologist Michela Johnson.
Ms Johnson realised it had been incorrectly classified and required a new scientific name, with the Lemmy inspiration coming from the Natural History Museum’s Lorna Steel.
“Although Lemmy passed away at the end of 2015, we’d like to think that he would have raised a glass to Lemmysuchus, one of the nastiest sea creatures to have ever inhabited the Earth,” Dr Steel said.
“As a long-standing Motorhead fan I am thrilled to have had the opportunity to immortalise the rock star in this way.”
Lemmysuchus was part of an extinct group of reptiles known as teleosaurs, which were distantly related to the crocodiles of today.
“It can be difficult to identify new species as we are normally working with incomplete fossil skeletons,” Ms Johnson, a PhD student, said.
“Following careful anatomical comparison, and by referring to the main specimen held at the Natural History Museum, we could see that most of the previous finds were actually from relatives of Lemmysuchus rather than the species itself, and we were able to assign a new name.”
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