I went overkill on my CRC entries when I initially set it up; I'm not sure if /all/ of them are necessary, but I did it basically to ensure the new species mirrored the old ones exactly.
So, as an example for Aqualish, they have entries at:
object/creature/player/aqualish.iff
object/creature/player/aqualish_female.iff
object/creature/player/aqualish_male.iff
object/creature/player/shared_aqualish_female.iff
object/creature/player/shared_aqualish_male.iff
So for a two-gender race, I have five entries in CRC. For a single-gender, I have three (using Devaronians as an example):
object/creature/player/devaronian.iff
object/creature/player/devaronian_male.iff
object/creature/player/shared_devaronian_male.iff
It's possible one or more entries is extraneous. I simply modeled off the preexisting races.