The bluehead shiner (''Pteronotropis hubbsi'')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 ...

, the shiners, daces and minnows. It is

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

to the central United States, where it is found in

Arkansas Arkansas ( ) is a landlocked state in the West South Central region of the Southern United States. It borders Missouri to the north, Tennessee and Mississippi to the east, Louisiana to the south, Texas to the southwest, and Oklahoma ...

Louisiana Louisiana ( ; ; ) is a state in the Deep South and South Central regions of the United States. It borders Texas to the west, Arkansas to the north, and Mississippi to the east. Of the 50 U.S. states, it ranks 31st in area and 25 ...

Texas Texas ( , ; or ) is the most populous U.S. state, state in the South Central United States, South Central region of the United States. It borders Louisiana to the east, Arkansas to the northeast, Oklahoma to the north, New Mexico to the we ...

, and

Oklahoma Oklahoma ( ; Choctaw language, Choctaw: , ) is a landlocked U.S. state, state in the South Central United States, South Central region of the United States. It borders Texas to the south and west, Kansas to the north, Missouri to the northea ...

. It was also once known from

Illinois Illinois ( ) is a U.S. state, state in the Midwestern United States, Midwestern United States. It borders on Lake Michigan to its northeast, the Mississippi River to its west, and the Wabash River, Wabash and Ohio River, Ohio rivers to its ...

.Ranvestel, A. W. and B. M. Burr
Conservation Assessment for Bluehead Shiner (''Pteronotropis hubbsi'').
USDA Forest Service, Eastern Region. June 15, 2002. In 2014, the status changed from

Data Deficient A data deficient (DD) species is one which has been categorized by the International Union for Conservation of Nature (IUCN) as offering insufficient information for a proper assessment of conservation status to be made. This does not necessaril ...

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 ...

. It is threatened by draining, filling, farming and flooding of backwater swamp habitat and overcollection for the aquarium trade.

Description

This minnow grows up to about 60 millimeters in maximum length. It is a dusky reddish orange along the back with a lighter belly. The chin is black and the top of the head is blue with a green

iridescence Iridescence (also known as goniochromism) is the phenomenon of certain surfaces that appear gradually to change colour as the angle of view or the angle of illumination changes. Iridescence is caused by wave interference of light in microstru ...

. The larger males have some iridescence on the dark dorsal fin. There is a broad, dark lateral stripe from the chin to the tail base. The mouth is upturned. The

lateral line The lateral line, also called the lateral line organ (LLO), is a system of sensory organs found in fish, used to detect movement, vibration, and pressure gradients in the surrounding water. The sensory ability is achieved via modified epithelia ...

is incomplete. This species is closely related to '' Pteronotropis welaka'', and the two form a

monophyletic group In biology, a clade (), also known as a monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach to taxonomy ...

Distribution

This fish lives in several drainages emptying into the

Mississippi River The Mississippi River is the main stem, primary river of the largest drainage basin in the United States. It is the second-longest river in the United States, behind only the Missouri River, Missouri. From its traditional source of Lake Ita ...

, including the Ouachita and

Atchafalaya River The Atchafalaya River () is a distributary of the Mississippi River and Red River of the South, Red River in south central Louisiana in the United States. It flows south, just west of the Mississippi River, and is the fifth largest river in N ...

s. It has not been collected in Illinois since the 1970s and is likely

extirpated Local extinction, also extirpation, is the termination of a species (or other taxon) in a chosen geographic area of study, though it still exists elsewhere. Local extinctions are contrasted with global extinctions. Local extinctions mark a chan ...

there.

Biology

The species is

sexually dimorphic Sexual dimorphism is the condition where sexes of the same species exhibit different Morphology (biology), morphological characteristics, including characteristics not directly involved in reproduction. The condition occurs in most dioecy, di ...

, with females lacking the iridescent blue coloration of the males. The males change in appearance as they age. In its "non-flag" or "initial" phase, a male is small with a shiny blue head and fins. When it enters its "flag" or "terminal" phase the following year, the male is larger with a deeper body and dark vertical bars along its sides, and its blue coloration fades. The terminal males are aggressive and

territorial A territory is an area of land, sea, or space, belonging or connected to a particular country, person, or animal. In international politics, a territory is usually a geographic area which has not been granted the powers of self-government, ...

. Females are sexually mature at one year of age and spawn in May through July, probably producing multiple clutches. The yellow-orange eggs are up to 1.2 millimeters wide and are adhesive on the substrate. Spawning activity has not been observed in nature. This species sometimes shares nesting sites with sunfishes such as the

warmouth The warmouth (''Lepomis gulosus'') is a freshwater fish of the sunfish family (biology), family (Centrarchidae) that is found throughout the eastern United States. Other local names include molly, redeye, goggle-eye, red-eyed bream, and strawber ...

(''Lepomis gulosus''). The male minnow may defend the nest site. The life span of the fish is generally less than two years. Adults of this species eat mainly tiny

crustacean Crustaceans (from Latin meaning: "those with shells" or "crusted ones") are invertebrate animals that constitute one group of arthropods that are traditionally a part of the subphylum Crustacea (), a large, diverse group of mainly aquatic arthrop ...

s such as water fleas and

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 ...

s, as well as chironomid fly larvae. Juvenile minnows may also eat

rotifer The rotifers (, from Latin 'wheel' and 'bearing'), sometimes called wheel animals or wheel animalcules, make up a phylum (Rotifera ) of microscopic and near-microscopic Coelom#Pseudocoelomates, pseudocoelomate animals. They were first describ ...

nematode The nematodes ( or ; ; ), roundworms or eelworms constitute the phylum Nematoda. Species in the phylum inhabit a broad range of environments. Most species are free-living, feeding on microorganisms, but many are parasitic. Parasitic worms (h ...

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 ...

s, and

algae Algae ( , ; : alga ) is an informal term for any organisms of a large and diverse group of photosynthesis, photosynthetic organisms that are not plants, and includes species from multiple distinct clades. Such organisms range from unicellular ...

. The fish lives in slow-moving and stagnant waters in muddy and sandy well-vegetated habitat types where there are hiding spots.

References

External links

* {{Authority control Pteronotropis Fish described in 1978 Taxa named by Reeve Maclaren Bailey Fish of the United States Taxonomy articles created by Polbot