Researchers at Yale University have named a newly discovered dinosaur Obamadon gracilis in honour of the US president's toothy grin.
The small, insect-eating lizard was first discovered in eastern Montana in 1974, but a recent re-examination showed the fossil had been wrongly classified as a Leptochamops denticulatus and was, in fact, a new species, researchers said.
Obamadon gracilis was one of nine newly discovered species reported in the Proceedings of the National Academy of Sciences.
In naming the new species, Yale scientists combined the Latin "Obamadon" for "Obama's teeth" and "gracilis," which means slender.
"The lizard has these very tall, straight teeth and Obama has these tall, straight incisors and a great smile," said Nick Longrich, a palaeontologist at the school in New Haven, Connecticut.
Like many other dinosaurs, the lizard died out about 65 million years ago when a giant asteroid struck earth, scientists say.
Longrich said he waited until after the recent US election to name the dinosaur.
"It would look like we were kicking him when he's down if he lost and we named this extinct lizard after him," he said in an interview.
"Romneydon" was never under consideration and "Clintondon" didn't sound good, said Longrich, who supported Hillary Clinton's failed run against Obama in the 2008 Democratic primary.
Obama is not the first politician whose name has been used to help classify organisms. Megalonyxx jeffersonii, an extinct species of plant-eating ground sloth, was named in honour of President Thomas Jefferson, an amateur palaeontologist who studied the mammal.
In 2005, entomologists named three species of North American slime-mould beetles agathidium bushi, agathidium cheneyi and agathidium rumsfeldi in honour of the then-president, vice president and secretary of defence.
Other celebrity names also have been used to name new species.
A small Caribbean crustacean has been named after reggae icon Bob Marley, an Australian horsefly has been named in honour of hip-hop star Beyonce, and an endangered species of marsh rabbit has been named after Playboy magazine founder Hugh Hefner.