You missed the bigger Pokemon reference in that series in the episode where they started getting obsessed with "Chinpokomon".http://southparkstudios-intl.mtvnimages.com/shared/sps/images/shows/southpark/vertical_video/season_15/sp_1510_08.jpg?width=480
This rat is clearly a rattata reference in the same way the OP pointed out a galvantula reference.
Pokemon Arceus was mentioned in House MD as well.LinkCosby: What do you like to play?
Cosby: Pok-ee-mon?! With the Pok-ee and the mon and the thing where the guy comes out of the thing...