There is already a lichen — Caloplaca obamae — and a worm — Paragordius obamai — named after Barack Obama. Now he also has Obamadon gracilis, an ancient, extinct, carnivorous lizard.
You can read a full write-up on Obamadon at Carolyn Johnson's Science in Mind blog. It includes some behind-the-scenes detail on the amusing considerations one has to take into account when one decides to name a specimen after a sitting president just before an election.
But I also wanted to take this opportunity to point you towards Curious Taxonomy, a fantastic list of creatures great and small and the sometimes surprising celebrities they have been named after. In the list you'll find a dinosaur named for Ross Perot, a ridiculous number of animals and plants named after Theodore and Franklin Roosevelt, and no fewer than three creatures named for Stephen Colbert.
And if you're noting that the selection of animals named in honor of Obama are not exactly the world's most flattering, never fear. Taxonomy is kind of bipartisan in its possibly-maybe-accidental insults. George W. Bush, Donald Rumsfeld, and Dick Cheney have a trio of slime mold beetles.