Snagrio
Fish Crazy
I forgot to mention, I've seen both my plecos flare out their odentales on occasion. But with mine they look more like little bunches of puff balls that stick out from their "cheeks" and not the anemone-looking horror show that the OP is dealing with. At the same time though, they do move like "grasping hands" as has been described about OP's issues so I think we can rule out some sort of macro parasite as the movement is from the pleco's own anatomy.
My guess is it's some kind of infection (possibly fungal) that's attached directly to the odentales.
My guess is it's some kind of infection (possibly fungal) that's attached directly to the odentales.