(written from a Production point of view)
Rick Ryan is an actor who played a Prytt guard in the Star Trek: The Next Generation seventh season episode "Attached" in 1993. He received no credit for this appearance but was identified by the name tag of his costume which was sold off on the It's A Wrap! sale and auction on eBay. 
Ryan was also featured as a Brakiri ambassador in the 1996 Babylon 5 episode "The Hour of the Wolf". This episode features fellow Trek performers Bill Mumy, Patricia Tallman, Andreas Katsulas and Bill Blair and was written by the series creator J. Michael Straczynski.