[3] It is endemic to Travis and Williamson counties, Texas, United States.

Eurycea tonkawae is the sister taxon to E. naufragia and E. chisholmensis, two other endemic perrenibranchiate central Texas salamanders.

Cave dwelling E. tonkawae may represent a distinct species, however further work is needed to clarify their taxonomic status.

Previous studies have shown highest abundance rates during rainfall seasons such as spring and summer.

[6][7] Eurycea tonkawae occur in a clumped-like distribution, only being found in the Jolleyville Plateau and Bushy Creek areas in Texas counties.