David Dimbleby has ruled out a return to the tattoo parlour to add legs to the scorpion on his shoulder.
The 75-year-old revealed his new tattoo in the Radio Times on Tuesday and told the magazine he chose the design to represent his star sign, Scorpio.
But his tattoo has six legs - while scorpions actually have eight.
The Question Time host told ITV's Loose Women he was "no David Attenborough" and did not spot legs were missing, adding he was not going to change it.
Dimbleby got the tattoo while making the maritime series, Britain and the Sea - to be shown on BBC One on Sunday - and told the Radio Times he had "always wanted a tattoo".
But the BBC News website spotted that his scorpion only had six legs and a London Zoo invertebrates expert said that he was "unaware" of any scorpions with fewer than eight legs.
However, thrash metal band Megadeth band used a six-legged scorpion on the cover of their 2004 single The Scorpion.
Speaking to ITV on Wednesday, the veteran broadcaster freely admitted the mistake, saying: "Apparently it should have eight legs, not six.
"I'm no David Attenborough, I didn't spot that but apparently there's a thrash metal band called Megadeth in America and Megadeth have a six-legged [scorpion] so I'm now a fan of Megadeth," he joked with Janet Street-Porter on the Loose Women chat show.
But when asked if he would be going back to have the extra legs added, he laughed: "I'm not going to do that."
The veteran broadcaster also said he was "not allowed to say" what his wife Belinda thought of him getting his first tattoo on his right shoulder.
But in his interview with the Radio Times he joked that she was "mildly amused" and added: "I believe she wanted a tattoo once, but has never got around to it. Maybe I'll be able to persuade her."