(written from a Production point of view)
Steve Casavant (also known as Steven Oliver) is an actor who appeared in over 10 episodes of the first season of Star Trek: The Next Generation. As a background actor he received no screen credit for his appearances. Oliver was hired to be the fitting model for the Starfleet uniforms and was hired as a background performer three months after this.
His Antican delegate character was identified by the name tag of his costume which was sold off on the It's A Wrap! sale and auction on eBay.  According to Casavant, "From Season 1,Episode 7 "Lonely Among Us" the Selay(Lizard Aliens) and the Antican (Doggish aliens) which I [w]as an extra got to spend 3 hours in make-up and wear for 12 hours. In one shot I was sitting on floor behind the main Dog star and they had me bark. That was all I ever got to say in my whole experience as an extra for NG StarTrek."