Patrick Schwarzenegger -- Busted For Speeding In Daddy's Car

Arnold Schwarzenegger's aspiring-model son Patrick earned the Schwarzenegger family yet another traffic ticket -- after the 18-year-old was cited for speeding in Santa Monica.

Law enforcement sources tell TMZ, Patrick was pulled over last week in Ahnald's 2009 black Audi after going 54 mph in a 35mph zone.

We're told Patrick was cited for the violation -- and sent away without further incident.