I'm not gonna delve into the ID specifics but for anyone else who wants to have a look (or just future me), genera in the area are: Culmacris and Bundinja.
Oh hang on, only two?? Okay surely we take a look then. Okay fairly easy, the very slender body form, elongate head, and the fact that the middle femur only juuuust doesn't fit nicely in front of the hind leg makes this Culmacris. Cool!
Ooh and Culmacris has been revised as well, fantastic! Purely from distribution I think it must be the Prairie Race of C. diversa.
Vivid yellow locust or grasshopper. Hundreds of these bright yellow insects were present near the cave entry.
Found on Senna artemisioides in semi arid woodlands around Kalgoorlie-Boulder. Parthenogenetic species. Juvenile female, instar 3 or 4.