Thanks Dogscoff!
The beings in question - the Verdurans - come from a rock homeworld with a carbon dioxide atmosphere. Have you ever read David Brin's Uplift series? I was thinking something like the Kanten. They are like a small tree or shrubbery with dark green leaves (with silver tips). They have no eyes, and they walk on root-like appendages. Aside from that basic description, feel free to be creative.
If it helps, here's a picture of their Battlecruiser:
[ February 10, 2003, 17:20: Message edited by: Chronon ]