The flame chub (''Hemitremia flammea'') 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 ...

s, Eurasian minnows and related species. This fish is found only in the United States. Its range broadly follows the

Tennessee River The Tennessee River is a long river located in the Southern United States, southeastern United States in the Tennessee Valley. Flowing through the states of Tennessee, Alabama, Mississippi, and Kentucky, it begins at the confluence of Fren ...

from above

Knoxville Knoxville is a city in Knox County, Tennessee, United States, and its county seat. It is located on the Tennessee River and had a population of 190,740 at the 2020 United States census. It is the largest city in the East Tennessee Grand Division ...

, Tennessee, to the mouth of the Duck River. Historically the species was found in

Kentucky Kentucky (, ), officially the Commonwealth of Kentucky, is a landlocked U.S. state, state in the Southeastern United States, Southeastern region of the United States. It borders Illinois, Indiana, and Ohio to the north, West Virginia to the ...

Tennessee Tennessee (, ), officially the State of Tennessee, is a landlocked U.S. state, state in the Southeastern United States, Southeastern region of the United States. It borders Kentucky to the north, Virginia to the northeast, North Carolina t ...

Alabama Alabama ( ) is a U.S. state, state in the Southeastern United States, Southeastern and Deep South, Deep Southern regions of the United States. It borders Tennessee to the north, Georgia (U.S. state), Georgia to the east, Florida and the Gu ...

and

Georgia Georgia most commonly refers to: * Georgia (country), a country in the South Caucasus * Georgia (U.S. state), a state in the southeastern United States Georgia may also refer to: People and fictional characters * Georgia (name), a list of pe ...

. The preferred habitat of flame chub is in small flowing streams often associated with springs.

Anatomy and appearance

The flame chub can be characterized by a deep caudal peduncle, short head and snout, small slightly subterminal mouth, and a barely compressed body. The dorsal fin originates slightly behind the pelvic fin origin. 7 – 8 anal soft rays, incomplete lateral line with 38 – 44 lateral scales, fewer than half of scales pored, pharyngeal teeth 2,5-4,2. Coloration is olive on the upper half of the body with a dark stripe along the back and dark streaks, bordered by a light stripe then black stripe ending at black caudal spot or wedge. White to red below, with bright scarlet along anterior third of body and at base of dorsal fin in large fish (primarily males) and silver peritoneum flecked with black. Males are more colorful than females, and both sexes are more colorful during spawning season. Flame chubs can grow to a maximum of long.Page, L.M. and B.M. Burr, 1991. A field guide to freshwater fishes of North America north of Mexico. Houghton Mifflin Company, Boston. 434 p.

Geographic distribution

Due to habitat alteration and destruction, the flame chub currently has a patchy range. The species primarily occurs in the Tennessee River Valley from the Knoxville, Tennessee area downstream through Alabama to the mouth of the Duck River in Tennessee. The majority of the population in Alabama resides in the Highland Rim or Cumberland Plateau regions. A single isolated population occurs in north Georgia in the Tiger Creek watershed of Catoosa County. In Alabama (which comprises approximately 50% of the remaining range of this species), only two populations are on public protected land, with the rest of the flame chub's habitat occurring on privately owned land. As such, the survival and further assessment of this species in Alabama is almost totally reliant on cooperation with private land owners.

Ecology

While often cited by literature that the flame chub inhabits spring-fed streams, shallow seepage waters, and springs, usually over gravel in areas of abundant aquatic vegetation, substrate the species found over can vary from bedrock to rubble to mud and may be found in areas of low flow near the bank of large streams. A study by P. W. Shute notes that although the flame chub is often described as a spring-dwelling species, only 37 of 231 collection localities were springs. Despite this, the species can still be found primarily in association with spring heads, as most collection localities are found within watersheds that are fed by springs. Most documented records of this species are found in small streams. It has been hypothesized that this species is migratory within its range, either travelling from its native stream to headwaters for spawning, or existing in

metapopulation A metapopulation consists of a group of spatially separated populations of the same species which interact at some level. The term metapopulation was coined by Richard Levins in 1969 to describe a model of population dynamics of insect pests in a ...

s with the springs serving as both sources for the stream localities and as refugia. It has also been observed that adult flame chubs may aggregate in flooded fields and pastures for spawning. Due to the fragile nature of springs and their tributaries, human expansion has caused further disjunction in the range of this already

narrow endemic Narrow may refer to: * The Narrow, rock band from South Africa * Narrow banking, proposed banking system that would eliminate bank runs and the need for a deposit insurance * Narrow-gauge railway, a railway that has a track gauge narrower than the ...

species. As of 2014,

IUCN The International Union for Conservation of Nature (IUCN) is an international organization working in the field of nature conservation and sustainable use of natural resources. Founded in 1948, IUCN has become the global authority on the status ...

considers this species to be Near Threatened due to ongoing threats from introduced non-native fish species and human habitat alteration. The temperature of sampled streams where flame chubs are known to occur ranged from in July to in February. TDS varied from 17 to 213 ppm, with a pH ranging from 6.4 to 8.2. In 1990, Sossamon recorded that a flame chub population in east Tennessee was normally found associated with aquatic vegetation such as swamp smartweed, small pondweed, and

watercress Watercress or yellowcress (''Nasturtium officinale'') is a species of aquatic flowering plant in the cabbage family, Brassicaceae. Watercress is a rapidly growing perennial plant native to Eurasia. It is one of the oldest known leaf vegetabl ...

. The flame chub almost exclusively (77–100% of the contents of the digestive tract) eats

dipteran Flies are insects of the order Diptera, the name being derived from the Greek δι- ''di-'' "two", and πτερόν ''pteron'' "wing". Insects of this order use only a single pair of wings to fly, the hindwings having evolved into advanced ...

larvae and pupae.

Gastropods Gastropods (), commonly known as slugs and snails, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, freshwater, and from the land. Ther ...

, aquatic

oligochaetes Oligochaeta () is a subclass of soft-bodied animals in the phylum Annelida, which is made up of many types of aquatic and terrestrial worms, including all of the various earthworms. Specifically, oligochaetes comprise the terrestrial megadril ...

hemiptera Hemiptera (; ) is an order of insects, commonly called true bugs, comprising more than 80,000 species within groups such as the cicadas, aphids, planthoppers, leafhoppers, assassin bugs, bed bugs, and shield bugs. They range in size from ...

ns, and

cladocera The Diplostraca or Cladocera, commonly known as water fleas, is a superorder (biology), superorder of small, mostly freshwater crustaceans, most of which feed on microscopic chunks of organic matter, though some forms are predatory. Over 1000 sp ...

ns are also taken occasionally. The occurrence of seeds, sand grains, and detritus in the gut of the flame chub indicates that flame chubs feed on or near the substrate. In observations in aquaria, the flame chub pecks at the substrate.

Life history

One Tennessee study of flame chub hatching found that hatching began in early May (and possibly earlier) and continued through late May. Gravel is a very important factor in the breeding patterns of these fish, as it is necessary for filtration of extremely clean water as well as bottom stability for a species that spends a lot of its time in the benthos area of the stream.Lachner, EA. 1950. The Comparative Food Habits of the Cyprinid Fishes Nocomis bigguttatus and Nocomis micropogon in Western New York. Journal of the Washington Academy of Sciences 40:229-236. No data are available pertaining to the species' lifespan.

Conservation and management

This species is currently listed as

near threatened A near-threatened species is a species which has been Conservation status, categorized as "Near Threatened" (NT) by the International Union for Conservation of Nature (IUCN) as that may be vulnerable to Endangered species, endangerment in the ne ...

according to the IUCN Red List. A study done near Chattanooga, Tennessee showed that where oxygen levels were high, and where well-forested rocky watersheds were found, that the density of the Flame Chub as well as similar fish were much higher.Long, J; Schorr, MS. 2005. Effects of watershed urban land use on environmental conditions and fish assemblages in Chattanooga area streams (Tennessee-Georgia). Journal of Freshwater Ecology: 527–537.

Habitat destruction Habitat destruction (also termed habitat loss or habitat reduction) occurs when a natural habitat is no longer able to support its native species. The organisms once living there have either moved elsewhere, or are dead, leading to a decrease ...

is one of the main causes of the decline of this species. It is sensitive to alteration of its habitat, and is now extirpated from Kentucky, and close to extirpation in Georgia. A 2007 survey in north Alabama recovered flame chubs at only 19 of 53 localities that in the 1960s still had populations. Many sites were obviously degraded by forms of land use change such as putting a stream in a concrete culvert, or paving over part of a stream.

References

{{Taxonbar, from=Q600194 Chubs (fish) Plagopterinae Fish described in 1870 Freshwater fish of the United States Taxa named by David Starr Jordan Taxa named by Charles Henry Gilbert Taxonomy articles created by Polbot