The fish with bumps on their heads that 14yearoldflyfisher was referring to are creek chubs, specifically the big males. They don't get 2 or 3 pounds, though. They look like this:
I've been down to Walls of Jericho on a hike, but didn't bother with a fishing rod. Now I may have to. I've never fished any of the Paint Rock River or tribs.
Some of the other fish you may have caught could have been redhorse species. Redhorse are suckers, and you said they didn't look like suckers. But here's a pic any way:
MAYBE somehow, some river herring, or a related species, got up that far during a spawn from Wheeler. They are usually fish of bigger rivers, but you never know. They look like this:
I'll bet you, if they WERE river herring, that you won't catch any this time of the year.
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