Duke, Lulu and Rockman
Duke is the apparent leader of the DinoRiders and is what appears to be a dark green Rex wearing a leather-jacket and brown helmet. Duke is also abnormally short. Rockman is Duke's right-hand man and is exceptionally huge and menacing-looking. Lulu is the final member of the gang and the only girl in it, she appears to be some kind of lizard.
The DinoRiders are first seen when Yoshi is running-away from home; the DinoRiders drive-up to Yoshi on their motorcycles and begin to question him. After learning that Yoshi knows Mario and Luigi, Duke allows Yoshi to join the DinoRiders; secretly though, the DinoRiders simply wanted to use Yoshi to get to the Mario Bros., who they planned to capture and sell to Bowser.
Manipulating Yoshi, the DinoRiders had the oblivious reptile commit several bad-deeds such as graffiti and "Stink Bob-ombing" a house before granting him "full membership" into the gang. Duke then had Yoshi tell Mario and Luigi to meet with the DinoRiders at the Tar Pit Milk Bar. Venturing to the bar, Mario and Luigi were captured by the DinoRiders, who set-off to Bowser's Neon Castle to turn the Bros. in.
While on their way to Neon Castle, the DinoRiders were ambushed by Yoshi and Princess Toadstool, who rescued Mario and Luigi from the DinoRiders. Stealing Lulu's motorcycle, Mario, Luigi, Yoshi and Princess Toadstool took-off, with the DinoRiders hot on their trail.
The DinoRiders were eventually defeated when, during a high-speed chase, Rockman was blasted into and deep-fried in a lava pit, while Duke and Lulu crashed into a wall. Duke, Lulu and Rockman were last seen staring into the Warp Tube that Mario, Luigi, Yoshi and Princess Toadstool had escaped down.