>>at least four (possibly five) separate sentient races
>
>Would the uncertainty be about whether the Gnards and Paeecs from
>Mars Attacks! are separate species or not?

Nope; it's generally accepted that the Fungus Heads (as the Tharks called them) were extrasolar invaders and not native to Mars in the first place. The uncertainty mainly stems from the fact that no one quite knows whether the White Martians (of Red Martian antiquity, not evil Malacandri) are really extinct, and if they're not, are they really a separate species from the Reds? Some scholars say yes, some say no.

--G.
-><-
Benjamin D. Hutchins, Co-Founder, Editor-in-Chief, & Forum Admin
Eyrie Productions, Unlimited http://www.eyrie-productions.com/
Ceterum censeo Carthaginem esse delendam.