Railroad Valley springfish
Encyclopedia
The Railroad Valley springfish Crenichthys nevadae, is a rare goodeid fish
of the Great Basin
of western North America
, occurring naturally in just seven thermal springs of Railroad Valley
in Nye County, Nevada
.
The body gives a somewhat heavy or massive impression, particularly forward, the head being almost as wide as deep. Each side has a distinctive row of dark blotches, with pale bars in between. The pelvic fins are entirely absent, while the anal fin is large, with 13 rays. The dorsal fin
is set far back on the body, just above the anal fin, and is somewhat smaller than the anal fin, with 12 rays.
This springfish is omnivorous, with animal food representing 2/3 or more of its consumption during the summer, primarily consisting of gastropods. Plant consumption is mostly filamentous algae
. While intestine length is consistent with an omnivore, Sigler & Sigler suggest that the high water temperatures of the springfish habitat may demand the higher energy available with animal food.
The warm springs in which these are found range in temperature from 77 to 102 degrees F (25 to 39 C).
Although the Railroad Valley springfish is not currently threatened with extinction, its extremely limited range makes it vulnerable to competition from introduced species, and to habitat modifications. For instance, it was nearly eliminated from Duckwater Spring in the early 1980s by introduced channel catfish
. The springfish has been introduced to Chimney Springs and in Hot Creek Canyon in Mineral County, Nevada
.
Fish
Fish are a paraphyletic group of organisms that consist of all gill-bearing aquatic vertebrate animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish, as well as various extinct related groups...
of the Great Basin
Great Basin
The Great Basin is the largest area of contiguous endorheic watersheds in North America and is noted for its arid conditions and Basin and Range topography that varies from the North American low point at Badwater Basin to the highest point of the contiguous United States, less than away at the...
of western North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
, occurring naturally in just seven thermal springs of Railroad Valley
Railroad Valley
Railroad Valley is one of the Central Nevada Desert Basins in the Tonopah Basin and is ~80 miles long north-south and up to 20 miles wide, with some southern areas running southwest to northeast. The southern end of the valley begins near Gray Top Mountain and stretches north all the way to...
in Nye County, Nevada
Nye County, Nevada
-National protected areas:* Ash Meadows National Wildlife Refuge* Death Valley National Park * Humboldt-Toiyabe National Forest * Spring Mountains National Recreation Area -Demographics:...
.
The body gives a somewhat heavy or massive impression, particularly forward, the head being almost as wide as deep. Each side has a distinctive row of dark blotches, with pale bars in between. The pelvic fins are entirely absent, while the anal fin is large, with 13 rays. The dorsal fin
Dorsal fin
A dorsal fin is a fin located on the backs of various unrelated marine and freshwater vertebrates, including most fishes, marine mammals , and the ichthyosaurs...
is set far back on the body, just above the anal fin, and is somewhat smaller than the anal fin, with 12 rays.
This springfish is omnivorous, with animal food representing 2/3 or more of its consumption during the summer, primarily consisting of gastropods. Plant consumption is mostly filamentous algae
Algae
Algae are a large and diverse group of simple, typically autotrophic organisms, ranging from unicellular to multicellular forms, such as the giant kelps that grow to 65 meters in length. They are photosynthetic like plants, and "simple" because their tissues are not organized into the many...
. While intestine length is consistent with an omnivore, Sigler & Sigler suggest that the high water temperatures of the springfish habitat may demand the higher energy available with animal food.
The warm springs in which these are found range in temperature from 77 to 102 degrees F (25 to 39 C).
Although the Railroad Valley springfish is not currently threatened with extinction, its extremely limited range makes it vulnerable to competition from introduced species, and to habitat modifications. For instance, it was nearly eliminated from Duckwater Spring in the early 1980s by introduced channel catfish
Channel catfish
Channel catfish, Ictalurus punctatus, is North America's most numerous catfish species. It is the official fish of Missouri, Iowa, Nebraska, Kansas, and Tennessee, and is informally referred to as a "channel cat". In the United States they are the most fished catfish species with approximately 8...
. The springfish has been introduced to Chimney Springs and in Hot Creek Canyon in Mineral County, Nevada
Mineral County, Nevada
Mineral County is a county located in the U.S. state of Nevada. As of the 2000 census, the population was 5,071. In 2009, it was estimated to have dropped to 4,662. Its county seat is Hawthorne.-History:...
.