Some Seahorse types brood/hatch their eggs in their mouths too.
BTW, every creature on the earth has been obseved yawning except the Seahorse.
No, this fish didn't get caught snacking. The male banded jawfish (Opistognathus macrognathus) holds brooding eggs in its mouth until they're ready to hatch. The photo was taken in Riviera Beach, Fla., by Steven Kovacs and won first place in the marine animal portrait category.