Riding a specific creature

[Devronq]

I was looking at the Ashworm Dragoon Prc and i though it was kinda kool to give bonuses while riding ashworms (the sand burrow abilities) are there any other classes feats etc that give you bonuses or a special effect that only works with a specific creature type? (in the way the ashworm dragoon does)

[Urpriest]

There are a couple different Dragonrider PrCs in a few places, and at least one Griffonrider. Pathfinder has a Mammoth rider (Knight of the Iron Glacier I think?)