''Percina roanoka'', the Roanoke darter, is a species of freshwater
ray-finned fish
Actinopterygii (; ), members of which are known as ray-finned fishes, is a class of bony fish. They comprise over 50% of living vertebrate species.
The ray-finned fishes are so called because their fins are webs of skin supported by bony or hor ...
, 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 subfamily botanical names with "-oideae", and zoologi ...
Etheostomatinae
Etheosomatidae 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 i ...
, part of the
family
Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...
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 more than ...
, which also contains the
perch
Perch is a common name for fish of the genus ''Perca'', freshwater gamefish belonging to the family Percidae. The perch, of which three species occur in different geographical areas, lend their name to a large order of vertebrates: the Percif ...
es,
ruffes and
pikeperches. It isnative to
Virginia
Virginia, officially the Commonwealth of Virginia, is a state in the Mid-Atlantic and Southeastern regions of the United States, between the Atlantic Coast and the Appalachian Mountains. The geography and climate of the Commonwealth ar ...
,
West Virginia
West Virginia is a state in the Appalachian, Mid-Atlantic and Southeastern regions of the United States.The Census Bureau and the Association of American Geographers classify West Virginia as part of the Southern United States while the Bur ...
and
North Carolina
North Carolina () is a state in the Southeastern region of the United States. The state is the 28th largest and 9th-most populous of the United States. It is bordered by Virginia to the north, the Atlantic Ocean to the east, Georgia and So ...
in the United States. It is found in the
Roanoke,
Tar
Tar is a dark brown or black viscous liquid of hydrocarbons and free carbon, obtained from a wide variety of organic materials through destructive distillation. Tar can be produced from coal, wood, petroleum, or peat. "a dark brown or black bit ...
, and
Neuse river systems, typically in small to medium size rivers. It is a colorful species with an average length of . It feeds on insect larvae and other small invertebrates, and spawns in late May and June. It is a common fish with a very wide range and the
International Union for Conservation of Nature
The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natu ...
has classified its conservation status as being of "
least concern
A least-concern species is a species that has been categorized by the International Union for Conservation of Nature (IUCN) as evaluated as not being a focus of species conservation because the specific species is still plentiful in the wild. T ...
".
Description
Breeding males have black heads and red or orange jaws. They have black spinal fins with orange bands. Their anal, pelvic and pectoral fins are white with transparent membranes. They have sides whose coloration ranges from dark brown to back, with blue, yellow or green highlights. Females and nonbreeding males are colored similarly, although their colors are less intense than those of breeding males.
The darter has from nine to twelve dorsal fin spines, seven to nine anal fins and nine to twelve dorsal fin rays. The darter has an average length of , although the maximum reported length of a specimen of ''P. roanoka'' is . The darter has a maximum life span of three years.
Distribution and habitat
The darter lives in the
drainage basin
A drainage basin is an area of land where all flowing surface water converges to a single point, such as a river mouth, or flows into another body of water, such as a lake or ocean. A basin is separated from adjacent basins by a perimeter, t ...
of the
Roanoke,
Tar
Tar is a dark brown or black viscous liquid of hydrocarbons and free carbon, obtained from a wide variety of organic materials through destructive distillation. Tar can be produced from coal, wood, petroleum, or peat. "a dark brown or black bit ...
, and
Neuse rivers in
Virginia
Virginia, officially the Commonwealth of Virginia, is a state in the Mid-Atlantic and Southeastern regions of the United States, between the Atlantic Coast and the Appalachian Mountains. The geography and climate of the Commonwealth ar ...
and
North Carolina
North Carolina () is a state in the Southeastern region of the United States. The state is the 28th largest and 9th-most populous of the United States. It is bordered by Virginia to the north, the Atlantic Ocean to the east, Georgia and So ...
. It is also found in the northern sections of the
James River
The James River is a river in the U.S. state of Virginia that begins in the Appalachian Mountains and flows U.S. Geological Survey. National Hydrography Dataset high-resolution flowline dataThe National Map , accessed April 1, 2011 to Chesapea ...
in Virginia and the
New River in West Virginia and Virginia.
The darter prefers to live in small to medium-sized rivers. Adults and juvenile ''Percina roanoka'' tend to live in
stream
A stream is a continuous body of water, body of surface water Current (stream), flowing within the stream bed, bed and bank (geography), banks of a channel (geography), channel. Depending on its location or certain characteristics, a stream ...
s and
riffle
A riffle is a shallow landform in a flowing channel. Colloquially, it is a shallow place in a river where water flows quickly past rocks. However, in geology a riffle has specific characteristics.
Topographic, sedimentary and hydraulic indica ...
s with gravel level
substrate. Younger juveniles tend to live in pools near the riffles.
Behavior
The darter
spawns
Spawn is the eggs and sperm released or deposited into water by aquatic animals. As a verb, ''to spawn'' refers to the process of releasing the eggs and sperm, and the act of both sexes is called spawning. Most aquatic animals, except for aquat ...
from late May to late June. In the New River, the darter has been observed reproducing with the
sharpnose darter to produce
hybrids.
The darter is a carnivore. It primarily consumes
chironomids
The Chironomidae (informally known as chironomids, nonbiting midges, or lake flies) comprise a family of nematoceran flies with a global distribution. They are closely related to the Ceratopogonidae, Simuliidae, and Thaumaleidae. Many species s ...
,
mayflies
Mayflies (also known as shadflies or fishflies in Canada and the upper Midwestern United States, as Canadian soldiers in the American Great Lakes region, and as up-winged flies in the United Kingdom) are aquatic insects belonging to the orde ...
and
black flies
A black fly or blackfly (sometimes called a buffalo gnat, turkey gnat, or white socks) is any member of the family Simuliidae of the Culicomorpha infraorder. It is related to the Ceratopogonidae, Chironomidae, and Thaumaleidae. Over 2,200 speci ...
.
Conservation status
The darter is ranked as
least-concern
A least-concern species is a species that has been categorized by the International Union for Conservation of Nature (IUCN) as evaluated as not being a focus of species conservation because the specific species is still plentiful in the wild. T ...
by the
International Union for Conservation of Nature
The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natu ...
. Reasons for this ranking include the darter's large habitat range, stable population size, large number of sub-populations and lack of major threats to its survival.
References
{{Taxonbar, from=Q3755744
roanoka
Fish of the United States
Fish described in 1889