Somehow, a fly, or a winged insect, gets into a character's mouth, sometimes by the character moving very fast.
Hilarity Ensues in many different ways, usually after gagging. Bonus points if someone convinces the swallower that they'll die because of it.
Examples:
Classical Mythology
- In Greek Mythology, Zeus swallows Metis after she transforms into a fly. Cranial pregnancy ensues.
Film
Live-Action TV
- On WKRP in Cincinnati, Les rode a motor scooter to work, and occasionally had the problem of bugs in his teeth.
Songs
- I know an old Lady who swallowed a fly but I don't know why she swallowed the fly...
- Vocaloid Kaito did this in I Wish They'd Just Die (Shineba ii Noni)
Video Games
- In Full Throttle, Ben chats with his old biker gang leader, Father Torque, while they're both in the middle of riding. Exhausting all conversation trees will cause Torque to say that he can't talk anymore because he's eating too many bugs.
Web Comics
- This strip
from The Oatmeal
- In Goblins, goblin children are named by the tribe's fortune teller, based on a prediction. One tribe with a particularly inept fortune teller (and even more inept scribes) has a member named Stop The Ceremony I Swallowed A Bug.
- The Serenity example is referenced in this
xkcd strip.
Web Original
- The Homestar Runner cartoon "Bug In Mouth Disease" features Homestar distraught because he accidentally swallowed a bug. "The good times are over!"
Western Animation
Real Life
- Truth in Television: notice the bugs on your windshield? It's very possible to have bugs collide with you at high speeds. If you don't have any protection and are currently talking or yawning or such, well...
- Meta example: one stock snark to someone who's either talking too much or has their jaw dropped in amazement is "Close your mouth before you start catching flies".