I figured I'd post about it here (while also hitting Google with a stick repeatedly) in case somebody will say "oh yeah that's [thing]!" :P
@green I found a thing that suggests it might be a quetzalcoatlus northropi (pictured) in this thread here: http://lists.urth.net/pipermail/urth-urth.net/2014-August/054976.html
@mawr that... makes a lot of sense, for the book, yes. and is quite possibly true! but it doesn't get me any closer to figuring out the picture in my head...
speaking of unreliable memory, I now have no idea if I ever actually saw this picture, or if I made it up or dreamed it or what. >___< if I was better at art I could draw it, it's so clearly in my mind! arrgh...
@green pls post if you find the answer since that sounds *rad*.