The Alvord chub Gila alvordensis is a rare cyprinid

Cyprinid

The family Cyprinidae, from the Ancient Greek kyprînos , consists of the carps, the true minnows, and their relatives . Commonly called the carp family or the minnow family, its members are also known as cyprinids...

 fish

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...

 endemic

Endemic (ecology)

Endemism is the ecological state of being unique to a defined geographic location, such as an island, nation or other defined zone, or habitat type; organisms that are indigenous to a place are not endemic to it if they are also found elsewhere. For example, all species of lemur are endemic to the...

 to the Alvord basin in southeastern Oregon

Oregon

Oregon is a state in the Pacific Northwest region of the United States. It is located on the Pacific coast, with Washington to the north, California to the south, Nevada on the southeast and Idaho to the east. The Columbia and Snake rivers delineate much of Oregon's northern and eastern...

 and northwestern Nevada

Nevada

Nevada is a state in the western, mountain west, and southwestern regions of the United States. With an area of and a population of about 2.7 million, it is the 7th-largest and 35th-most populous state. Over two-thirds of Nevada's people live in the Las Vegas metropolitan area, which contains its...

, USA, known only from a few springs, streams, and marshes in the Sheldon National Wildlife Refuge

Sheldon National Wildlife Refuge

The Sheldon National Wildlife Refuge is a national wildlife refuge located on the northern border of the U.S. state of Nevada. A very small part extends northward into Oregon. It is managed by the United States Fish and Wildlife Service as the Nevada component of the Sheldon-Hart Mountain...

, and one location elsewhere.

The Alvord chub is a small fish, with adults ranging up to 14 cm in length, but with many half that size. It is generally grayish-whitish, darker on the back than below, and with a faint band passing down the sides. The dorsal fin has 7 rays, the anal fin 8 rays, and the tail 19 rays.

Studies of the fish's diet shows it is an opportunistic feeder, consuming a variety of aquatic invertebrates, with a considerable percentage of midge

Midge (insect)

Midges comprise many kinds of very small two-winged flies found world-wide. The term does not encapsulate a well-defined taxonomic group, but includes animals in several families of Nematoceran Diptera. While some midges are vectors for disease, many others play useful roles as prey items for...

 larvae. It occupies a variety of habitats within its range, including waters of depths 3 inches to 3 feet, different bottoms including gravel and silt, and any amount of cover over the water. It can be found in warm springs, up to 80 degrees Fahrenheit, but not in hot springs.

Spawning season lasts from April to July.

Although apparently doing well in its location, the species is considered vulnerable because of its very limited range in a fragile environment

Natural environment

The natural environment encompasses all living and non-living things occurring naturally on Earth or some region thereof. It is an environment that encompasses the interaction of all living species....

. Having evolved

Evolution

Evolution is any change across successive generations in the heritable characteristics of biological populations. Evolutionary processes give rise to diversity at every level of biological organisation, including species, individual organisms and molecules such as DNA and proteins.Life on Earth...

without any competition, there is concern over the possible effects of exotic fish introduction, whether deliberate or accidental.