The Roanoke logperch (''Percina rex'') is a

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

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 ...

, a darter from the

subfamily In biological classification, a subfamily (Latin: ', plural ') is an auxiliary (intermediate) taxonomic rank, next below family but more inclusive than genus. Standard nomenclature rules end botanical subfamily names with "-oideae", and zo ...

Etheostomatinae Etheostomatinae is a species-rich subfamily of freshwater ray-finned fish, the members of which are commonly known as the darters. The subfamily is part of the family Percidae which also includes the perches, ruffes and pikeperches. The family ...

, part of 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 ...

Percidae The Percidae are a family of ray-finned fish, part of the order Perciformes, which are found in fresh and brackish waters of the Northern Hemisphere. The majority are Nearctic, but there are also Palearctic species. The family contains nearly 250 ...

, which also contains the

perch Perch is a common name for freshwater fish from the genus ''Perca'', which belongs to the family Percidae of the large order Perciformes. The name comes from , meaning the type species of this genus, the European perch (''P. fluviatilis'') ...

es, ruffes and pikeperches. It is found in the Roanoke and Chowan drainages in

Virginia Virginia, officially the Commonwealth of Virginia, is a U.S. state, state in the Southeastern United States, Southeastern and Mid-Atlantic (United States), Mid-Atlantic regions of the United States between the East Coast of the United States ...

and

North Carolina North Carolina ( ) is a U.S. state, state in the Southeastern United States, Southeastern region of the United States. It is bordered by Virginia to the north, the Atlantic Ocean to the east, South Carolina to the south, Georgia (U.S. stat ...

in the

United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...

. It inhabits low and moderate-gradient streams and rivers in warm, clear water in mostly unsilted gravel and rubble in runs, pools, and riffles. It is primarily

insectivorous A robber fly eating a hoverfly An insectivore is a carnivorous animal or plant which eats insects. An alternative term is entomophage, which can also refer to the human practice of eating insects. The first vertebrate insectivores we ...

. This fish is a federally listed endangered species.

Description

As an adult the Roanoke logperch is between

standard length Fish measurement is the measuring of individual fish and various parts of fish anatomy, their anatomies, for data used in many areas of ichthyology, including Taxonomy (biology), taxonomy and fishery biology. Overall length Standard length (SL) is ...

, with a total length up to . The light-colored body is somewhat stocky and elongated. There are dark, rounded, and vertically elongated blotches on the side. The fish has a long, cone-shaped snout with a bulbous or blunt tip. There are two dorsal fins, which are both very tall on adult males. The first dorsal fin has an orange band bordered on both sides by black bands. The end of the tail fin is almost straight. The fins have black or brown dark marks on them. The large eyes are near the top of the head of the fish. The fish's upper jaw is longer than its lower jaw.

Distribution and habitat

The Roanoke logperch is known only from the upper reaches of the Roanoke, Dan and Chowan river systems in Virginia, with a small population in North Carolina. It inhabits gravel and boulder runs of slow-moving, warm, small to medium-sized rivers where it is found in riffles, runs and pools with sandy, stony or boulder-strewn bottoms.

Behavior

''P. rex'' is

sexually mature Sexual maturity is the capability of an organism to reproduce. In humans, it is related to both puberty and adulthood. ''Puberty'' is the biological process of sexual maturation, while ''adulthood'', the condition of being socially recognized as ...

by about two to three years of age.

Spawning Spawn is the Egg cell, eggs and Spermatozoa, sperm released or deposited into water by aquatic animals. As a verb, ''to spawn'' refers to the process of freely releasing eggs and sperm into a body of water (fresh or marine); the physical act is ...

occurs from mid-April to early May in water . Each female may produce from 200 to 650 eggs. The eggs are adhesive to surfaces and found on the bottom of the stream or pool. The Roanoke logperch uses its conical snout to turn over gravel and feed on exposed invertebrates. This enables it to reach prey sheltered beneath rocks that may be unavailable to other benthic fishes; however, this feeding behavior relies on the availability of loosely embedded

substrate Substrate may refer to: Physical layers *Substrate (biology), the natural environment in which an organism lives, or the surface or medium on which an organism grows or is attached ** Substrate (aquatic environment), the earthy material that exi ...

. In an

ecosystem An ecosystem (or ecological system) is a system formed by Organism, organisms in interaction with their Biophysical environment, environment. The Biotic material, biotic and abiotic components are linked together through nutrient cycles and en ...

, the Roanoke logperch can be an indication that the

river A river is a natural stream of fresh water that flows on land or inside Subterranean river, caves towards another body of water at a lower elevation, such as an ocean, lake, or another river. A river may run dry before reaching the end of ...

lake A lake is often a naturally occurring, relatively large and fixed body of water on or near the Earth's surface. It is localized in a basin or interconnected basins surrounded by dry land. Lakes lie completely on land and are separate from ...

has very low

turbidity Turbidity is the cloudiness or haziness of a fluid caused by large numbers of individual particles that are generally invisible to the naked eye, similar to smoke in air. The measurement of turbidity is a key test of both water clarity and wa ...

Conservation status

The Roanoke logperch is rated by the

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 ...

as being " vulnerable". The threats it faces are from

urbanization Urbanization (or urbanisation in British English) is the population shift from Rural area, rural to urban areas, the corresponding decrease in the proportion of people living in rural areas, and the ways in which societies adapt to this change. ...

, the impoundment of water resulting in the silting of waterways, and industrial and

agricultural pollution Agricultural pollution refers to biotic and abiotic byproducts of farming practices that result in contamination or degradation of the environment and surrounding ecosystems, and/or cause injury to humans and their economic interests. The po ...

. Nevertheless, the population seems fairly stable and may be increasing slightly in the

Pigg River The Pigg River is a river in south-west Virginia in the United States. It is a tributary of the Roanoke River, which flows to the Atlantic Ocean via Albemarle Sound. The Pigg River rises on Fivemile Mountain in western Franklin County and flows ...

In popular culture

In 2023 the Roanoke logperch was featured on a

United States Postal Service The United States Postal Service (USPS), also known as the Post Office, U.S. Mail, or simply the Postal Service, is an independent agencies of the United States government, independent agency of the executive branch of the federal governmen ...

Forever stamp as part of the ''Endangered Species'' set, based on a photograph from Joel Sartore's ''Photo Ark''. The stamp was dedicated at a ceremony at the National Grasslands Visitor Center in

Wall, South Dakota Wall (Lakota language, Lakota: ''Makȟóšiča Aglágla Otȟuŋwahe'', "Town alongside the Badlands National Park, Badlands") is a town in Pennington County, South Dakota, Pennington County, South Dakota, United States. The population was 699 at ...

References

{{Taxonbar, from=Q3755366 Percina Fish described in 1889 Endemic fish of the United States Taxa named by David Starr Jordan Taxa named by Barton Warren Evermann