Can't unlock "suffer not the alien" achievement

[Arothon]

I do not think anybody but the Paradox Programmers could answer that. This odd case might simply be a oversight, where you can not purge but they are also different.
The purge viability check uses the same code to differentiate a species. So if you can not purge them while on "Xeno's Only", then they should not count as seperate species for the Archievement purposes.

Hope you are right.

Darth Hammer i changed only "humans" into the german word "Menschen", also the adjective and called "Earth" to "Erde", not more.
I have the possibility to modify the Earth-Humans like my humans but the ethics are different. Dont know if that blocks to get the humans one in the species-list