Park Closure Alert . . .

Endangered Species and San Solomon Springs

San Solomon Springs in Balmorhea State Park is the largest group of springs issuing from the San Solomon Springs system. The system includes Phantom Lake (a.k.a. Phantom Cave Spring), Giffin, and East and West Sandia springs.

San Solomon Springs was considered the ninth largest spring in Texas (based on volume of water produced). Now it would rank as the fifth or sixth largest spring in Texas, given the decreased (or ceased) flows from Goodenough (was third), San Antonio (was sixth), Hueco (was seventh), and Comanche (was eighth) springs.

San Solomon Springs provides important habitat for two fresh­water springsnails (Gastropoda : Hydrobiidae), the Phantom springsnail (Pyrgulopsis texana) and the Phantom tryonia (Tryonia cheatumi); one crustacean, the Diminutive amphipod (Gammarus hyalleloides); and two species of fish, the Comanche Springs pupfish (Cyprinodon elegans) and the Pecos gambusia (Gambusia nobilis) that are unique to West Texas.

Solomon Springs is the largest spring in the Balmorhea area, and the habitat at Balmorhea State Park is very important for con­ser­ving these species.

Springsnails

Phantom springsnail (aka Phantom Cave springsnail), Pyrgulopsis texana

Texas Status

Endangered

U.S. Status

Endangered, Listed 7/9/2013

Description

The Phantom springsnail is a small snail with a smooth shell shaped somewhat like a flattened top. When fully grown, they measure only 0.98 – 1.27 millimeters (mm), which is the size of a coarse grain of sand.

Life History

Like other springsnails, the Phantom springsnail is strictly aquatic, with res­pi­ration occurring through an internal gill. Male and fe­male shells have slightly different shapes; fe­males are char­ac­ter­is­tically larger and longer-lived. Scientists don’t know the lifespan of the Phantom springsnail, but most aquatic snails live between 6 and 15 months. They feed on the biofilm (mixture of algae and mi­crobes) that develops on mud, rock, and vegetation.

Habitat

Springsnails are sensitive to water quality changes, and are typically found in highest abundances near spring openings and outflows. Scientists have shown that several habitat parameters of springs, such as water temperature, substrate type, water depth, and dis­solved oxygen, in­flu­ence the distribution and abundance of springsnails.

Distribution

The Phantom springsnail reportedly occurs only in four remaining desert spring outflow channels associated with the San Solomon Springs system: San Solomon, Giffin, Phantom Cave, and East Sandia springs.

Other

Phantom Cave Springs, once recognized as the 17th largest spring in the state, stopped flowing in the late 1990s. Since then, Phantom Cave Springs only flow for a short period after heavy local rains. A pump system that delivers water from the cave to a small man-made pool on the surface at the mouth of the cave sustains habitat for the endangered species. The Phantom springsnail is currently abundant in this man-made pool, but the system is clearly on life support.

Phantom tryonia (aka Cheatum’s snail), Tryonia cheatumi

Texas Status

Two small snailsEndangered

U.S. Status

Endangered, Listed 7/9/2013

Description

The Phantom tryonia is a small snail with a smooth, conical shell. It is slightly larger than the Phantom springsnail, with adults measuring 2.9-3.6 mm long.

Life History

Like other springsnails, the Phantom tryonia is strictly aquatic, with respiration occurring through an internal gill. Male and female shells are slightly different in shape, and females are characteristically larger and longer-lived. Scientists don’t know the lifespan of the Phantom tryonia, but most aquatic snails live between 6 and 15 months. They feed on the biofilm (mixture of algae and microbes) that develops on mud, rock, and vegetation.

Habitat

Springsnails are sensitive to water quality changes and are typically found in highest abundances near spring openings and outflows. Scientists have shown that several habitat parameters of springs, such as water temperature, substrate type, water depth, and dissolved oxygen, in­flu­ence the distribution and abundance of springsnails. Phantom tryonia are usually found near the spring source, and are most abundant within stands of sub­plants in the swimming area in Balmorhea State Park.

Distribution

The Phantom tryonia occurs only in four remaining desert spring outflow channels associated with the San Solomon Springs system: San Solomon, Giffin, Phantom Cave, and East Sandia springs.

Crustaceans

Diminutive amphipod, Gammarus hyalleloides

Texas Status

Small shrimp-like creature in water.Endangered

U.S. Status

Endangered, Listed 7/9/2013

Description

Amphipods in the Family Gammaridae are small inland crus­ta­ceans, some­times called freshwater shrimp. The Di­min­u­tive amphipod’s name refers to its size; it is the smallest of the known freshwater Gam­ma­rus amphipods. Adults range from 5 to 8 mm long.

Life History

Amphipods generally eat algae, sub­merged plants and decaying organic matter. They help process nutrients in aquatic eco­sys­tems and are sensitive to changes in habitat conditions.

Amphipods form breeding pairs that remain attached for 1 to 7 days at or near the substrate while continuing to feed and swim. Females hold the amphipod eggs within a marsupium, or brood pouch, in their exoskeletons. They produce from 15 to 50 off­spring that form a brood.

Habitat

Gammarid amphipods generally prefer shallow, cool, well-oxygenated waters. The Diminutive amphipod is found in desert spring outflow channels within interstitial spaces on and underneath rocks and within gravels or in dense stands of submerged plants, algae, or moss.

Distribution

The Diminutive amphipod occurs only in four West Texas springs; San Solomon, Giffin, Phantom Cave and East Sandia.

Other

Scientists think freshwater amphipods derived from a widespread ancestral marine amphipod isolated inland during the recession of the Late Cretaceous sea, about 66 million years ago. They likely evolved into distinct species during dry periods following sep­a­ration and isolation in remnant aquatic habitats associated with springs.

Fish

Comanche Springs pupfish, Cyprinodon elegans

Pecos gambusia, Gambusia nobilis

Desert Spring Fishes