Split species slavery! Can I?

[Space Knight]

I am playing an authoritarian militarist and got the Worm event. I played through it to the end and ended up with two variants of my base species.

I wanted to have one enslave the other (made sense considering what happens to the home system), but I cannot seem to figure out how to do it since both offshoots are considered the main species.

Anyone know how to do so?

 

[AGenericAccount]

You'll need the slaver guild civic to partially enslave a race.

 

[Ramiel]

Can't you set species rights for sub-species individually? I'll have to go check, if not that seems like a terrible oversight.
Might need Slaver Guilds to enslave a subspecies of your primary species though - and if so, that also seems like an oversight.