Heterelmis comalensis

It is endemic to Texas[1] in the United States, where it occurs in only two springs.

It occurs in shallow water in the gravel substrate and in riffles.

[3] It lives alongside other species such as the beetle Microcylloepus pusillus.

[5] The main threat to this rare species is the slow loss of the Edwards Aquifer, which has long been tapped for its water.

[3] Some specimens are kept in captivity at the San Marcos National Fish Hatchery and Technology Center, and some larvae have been produced.