The Borax Lake chub (''Siphateles boraxobius'') is a species of freshwater

ray-finned fish Actinopterygii (; ), members of which are known as ray-finned fish or actinopterygians, is a class of bony fish that comprise over 50% of living vertebrate species. They are so called because of their lightly built fins made of webbings of sk ...

belonging to the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Leuciscidae Leuciscidae is a family of freshwater ray-finned fishes, formerly classified as a subfamily of the Cyprinidae, which contains the true minnows. Members of the Old World (OW) clade of minnows within this subfamily are known as European minnow ...

, which includes the

dace A dace is a small fish that can be one of many different species. The unmodified name is usually a reference to the common dace (''Leuciscus leuciscus''). This, like most fish called "daces", belongs to the family Leuciscidae, mostly in subfami ...

chub Chub is a common fish name. It pertains to any one of a number of ray-finned fish in several families and general. In the UK, the term ''chub'' usually refers to the species '' Squalius cephalus''. In addition, see sea chub. In family Cyprinid ...

Eurasian minnow ''Phoxinus'' is a genus of freshwater fish in the family Leuciscidae of order Cypriniformes, and the only members of the subfamily Phoxininae, or Eurasian minnows. The other species in this genus are also commonly known as minnows. The name "minn ...

s and related fishes. This is a rare species which is found only in outflows and pools around Borax Lake, a small lake of the Alvord basin,

Harney County, Oregon Harney County is one of the List of counties in Oregon, 36 counties in the U.S. state of Oregon. As of the 2020 United States census, 2020 census, the population was 7,495, making it the sixth-least populous county in Oregon. The county seat i ...

. This species typically reaches only in length, although some are as long as . The back is generally a dark olive green, while the sides are silvery, with a dark line extending from gill cover to tail, and a scattering of dark

melanophore Chromatophores are cells that produce color, of which many types are pigment-containing cells, or groups of cells, found in a wide range of animals including amphibians, fish, reptiles, crustaceans and cephalopods. Mammals and birds, in contrast ...

s. The fins are colorless, with more melanophores on the rays of the dorsal fin and tail, as well as on the first four rays of the pectoral fins. Similar in many ways to the

Alvord chub The Alvord chub (''Siphateles alvordensis'') is a species of freshwater ray-finned fish belonging to the family Leuciscidae, which includes the daces, chubs, Eurasian minnows and related fishes. This is a rare species which is endemic to the A ...

, the Borax Lake species has a longer, wider, and deeper head, and larger eyes, and the

caudal peduncle Fins are moving appendages protruding from the body of fish that interact with water to generate thrust and help the fish swim. Apart from the tail or caudal fin, fish fins have no direct connection with the back bone and are supported only ...

is more slender. Boraxlake

The Borax Lake chub eats a variety of foods, including

midge A midge is any small fly, including species in several family (biology), families of non-mosquito nematoceran Diptera. Midges are found (seasonally or otherwise) on practically every land area outside permanently arid deserts and the frigid ...

larvae,

diatom A diatom (Neo-Latin ''diatoma'') is any member of a large group comprising several Genus, genera of algae, specifically microalgae, found in the oceans, waterways and soils of the world. Living diatoms make up a significant portion of Earth's B ...

copepod Copepods (; meaning 'oar-feet') are a group of small crustaceans found in nearly every freshwater and saltwater habitat (ecology), habitat. Some species are planktonic (living in the water column), some are benthos, benthic (living on the sedimen ...

ostracod Ostracods, or ostracodes, are a Class (biology), class of the crustacean, Crustacea (class Ostracoda), sometimes known as seed shrimp. Some 33,000 species (only 13,000 of which are extant taxon, extant) have been identified,Brandão, S.N.; Antoni ...

s, and terrestrial insects. Its preferred mode of feeding is to root around in the bottom, but it will go after floating material or feed from the surface if necessary. This species is the sole fish inhabiting the Borax Lake waters. While parts of the lake itself can, at times, rise to about fed from thermal springs, the average temperature ranges between . The fish avoid the warmest water, favoring lake's outflows. Its continued existence was threatened by

geothermal energy Geothermal energy is thermal energy extracted from the crust (geology), crust. It combines energy from the formation of the planet and from radioactive decay. Geothermal energy has been exploited as a source of heat and/or electric power for m ...

development near the lake, which dried up part of the chub's habitat. However, in 2000 the Steens Mountain Cooperative Management and Protection Act put the area around the lake off-limits to geothermal exploration and mining. It was listed as an endangered species by the U.S. Fish and Wildlife Department from 1980, when it was listed under an emergency rule that was made permanent in 1982, until July 2020, when it was delisted due to recovery.

The Nature Conservancy The Nature Conservancy (TNC) is a global environmental organization headquartered in Arlington, Virginia, United States. it works via affiliates or branches in 79 countries and territories, as well as across every state in the US. Founded in ...

had bought Borax Lake and surrounding land for conservation management in the interim.

References

* Listed as Vulnerable (VU D2 v3.1) * * William F. Sigler and John W. Sigler, ''Fishes of the Great Basin'' (Reno: University of Nevada Press, 1987), pp. 170–173 Borax lake panorama

{{Authority control Borax Lake Siphateles Endemic fauna of Oregon Endemic fish of the United States Fish of the Western United States Freshwater fish of the United States Natural history of Oregon Fish described in 1980