Barton Springs salamander (endemic, hard to find)

The Barton Springs salamander (Eurycea sosorum) is a federally endangered salamander found only in the spring-fed waters and spring outlets of Barton Springs in Austin. The species has an extremely limited range and cryptic, aquatic habits, which make it difficult to detect without targeted surveys. Barton Springs Pool maintains a relatively constant temperature (about 68–70°F) year-round because it is fed by the Edwards Aquifer, which supports the salamander's habitat.