You want flightless dragons?
Here is one.
Spinolurus is a relative of Aviiguana [link]
and live partially in the same habitats.
This dragon is a omnivore. It's love insects (especial ants), fruits, grass, roots, carrion, small mammels, fish and so on...
During the dry season they come together in caves and sleep for months.
With their small wings they can't fly but are able to swim. Sometimes you can see them hunting fish in rivers or wallow in the mud.
In the mating season the wings of the males become bright yellow and they fight for the females. The tumult is often hearing miles away.