The Edwards Plateau is a geographic region at the crossroads of Central, South, and West Texas. It is bounded by the Balcones Fault to the south and east, the Llano Uplift and the Llano Estacado to the north, and the Pecos River and Chihuahuan Desert to the west. San Angelo, Austin, San Antonio, and Del Rio roughly outline the area. The southeast portion of the plateau is known as the Texas Hill Country.
The Leon Springs pupfish is a species of fish in the family Cyprinodontidae. It is endemic to Pecos County, Texas in the United States. It is a federally listed endangered species.
The Comanche Springs pupfish is a species of pupfish in the family Cyprinodontidae. It is endemic to Texas, and is now found only in spring-fed pools near Balmorhea, a small town in West Texas.
The San Bernardino springsnail is an endangered species of freshwater snail in the family Hydrobiidae. This species is endemic to a small number of springs in the USA and northern Mexico.
The Bruneau hot springsnail, scientific name Pyrgulopsis bruneauensis, is a species of very small freshwater snail that has a gill and an operculum, an aquatic gastropod mollusk in the family Hydrobiidae. This species is endemic to the United States, Bruneau River in Idaho. Its natural habitat is thermal springs. It is threatened by habitat loss.
The Chupadera springsnail, scientific name Pyrgulopsis chupaderae, is a species of minute freshwater snails with an operculum, aquatic gastropod molluscs or micromolluscs in the family Hydrobiidae.
The Page springsnail is a species of freshwater snail in the family Hydrobiidae, the mud snails. It is endemic to Arizona in the United States, where it is known only from the Upper Verde River drainage in Yavapai County.
Marstonia ogmorhaphe, common names the royal marstonia or royal springsnail, is a minute species of freshwater snail, an aquatic gastropod mollusk or micromollusk in the family Hydrobiidae, the mud snails. This species is endemic to Tennessee in the United States, where it occurs in two streams in Marion County. It is a federally listed endangered species of the United States.
Tryonia alamosae, common name the Alamosa springsnail, is a species of small freshwater snail, an aquatic prosobranch gastropod mollusk in the family Hydrobiidae.
Brune's tryonia, scientific name Tryonia brunei, is a species of very small freshwater snail that has a gill and an operculum, an aquatic gastropod mollusks in the family Hydrobiidae. This species is endemic to the United States (Texas). It was formerly listed as Threatened in 1993/1994 and Data Deficient since 1996 until it was changed to Critically Endangered and possibly extinct in 2012; this is because it is found only in Phantom Lake, Balmorhea Lake, has range of less than 100 km², and was last observed in 1993. A 1991 report by the United States Fish and Wildlife Service also listed it as Endangered and they also later noted the unknown population. It is found in firm substratum and on mud before modification.
The Kretschmarr Cave mold beetle is a small mold beetle.
Assiminea grayana, common name the "dun sentinel", is a species of very small (4–6 mm.) salt marsh snail, a terrestrial (or marine gastropod mollusk in the family Assimineidae.
The Socorro springsnail, scientific name Pyrgulopsis neomexicana, is an endangered species of minute freshwater snail with a gill and an operculum, an aquatic gastropod mollusk or micromollusk in the family Hydrobiidae, the mud snails.
The San Bernardino National Wildlife Refuge is located on the U.S.-Mexican border in Cochise County, Arizona. Situated at 3,720 to 3,920 feet (1,130–1,190 m) elevation in the bottom of a wide valley, the refuge encompasses a portion of the headwaters of the Yaqui River, which drains primarily western Chihuahua and eastern Sonora, Mexico. The 2,309-acre (9.34 km2) ranch was acquired by the U.S. Fish and Wildlife Service in 1982 to protect the water resources and provide habitat for endangered native fishes.
Balcones Canyonlands is a national wildlife refuge located in the Texas Hill Country to the northwest of Austin. The refuge was formed in 1992 to conserve habitat for two endangered songbirds, the golden-cheeked warbler and the black-capped vireo, and to preserve Texas Hill Country habitat for numerous other wildlife species. The refuge augments a similarly named preserve in Austin called the Balcones Canyonlands Preserve.
Stygoparnus is a monotypic genus of beetles containing the single species Stygoparnus comalensis, which is known by the common name Comal Springs dryopid beetle. This rare beetle is endemic to Texas in the United States, where it is known from two springs. It is a federally listed endangered species of the United States.
Rhadine persephone is a rare species of beetle known by the common name Tooth Cave ground beetle. It is endemic to Texas in the United States, where it occurs in a network of caves outside Austin. It is a federally listed endangered species of the United States.
Texella reyesi is a rare species of arachnid known by the common name Bone Cave harvestman. It is endemic to Texas in the United States, where it lives in limestone caves in Travis and Williamson Counties. It is threatened by the loss of its habitat. It is a federally listed endangered species of the United States.
Cicurina vespera is a rare species of spider in the family Dictynidae known by the common name Government Canyon Bat Cave meshweaver. It is endemic to Texas in the United States, where it is known from only one cave in Bexar County. This is one of nine invertebrates endemic to the karst caves of Bexar County that were federally listed as endangered species in the year 2000.
Cicurina baronia is a rare species of spider in the family Hahniidae known by the common name Robber Baron cave meshweaver. The species is endemic to the San Antonio, Texas area of the United States. It is one of nine species deemed the Bexar County Invertebrates, as all nine are found in similar cave environments in the central region of Texas. These species range in size from one millimetre to one centimetre. They are also eyeless or essentially eyeless and pale in coloration.
