Etheosomatidae is a species rich subfamily 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 h ...

, the members of which are commonly known as the darters. The subfamily is part of the

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

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 ...

which also includes 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 Per ...

es, ruffes and pikeperches. The family is

endemic Endemism is the state of a species being found 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 found else ...

to North America. It consists of 3-5 different genera and well over 200 species.

Characteristics

Species within the Etheostomatinae are all small fish, mostly less than in length and their bodies are slightly compressed or fusiform in shape. They have two pterygiophores between the first and second

dorsal fin A dorsal fin is a fin located on the back of most marine and freshwater vertebrates within various taxa of the animal kingdom. Many species of animals possessing dorsal fins are not particularly closely related to each other, though through c ...

s which do not have spines and a reduced

swimbladder The swim bladder, gas bladder, fish maw, or air bladder is an internal gas-filled organ that contributes to the ability of many bony fish (but not cartilaginous fish) to control their buoyancy, and thus to stay at their current water depth wit ...

which may be completely lacking. The name darter becomes because these fish are seen to dart around in their habitat and these fish have benthic habits. They are

sexually dimorphic Sexual dimorphism is the condition where the sexes of the same animal and/or plant species exhibit different morphological characteristics, particularly characteristics not directly involved in reproduction. The condition occurs in most ani ...

and most species have males with bright colours and patterning, particularly when breeding and these colours and patterns are used to attract females and allow for recognition of species as the colours and patterns are particular to each species. Many species use typical sites for

spawning 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 ...

and they care for their eggs and fry. They have evolved a variety of methods of depositing eggs and these include burying them, which may be the basal habit as it is found in all genera, as well as attaching eggs to a substrate and egg clustering.

Distribution

Etheostomatinae darters are endemic to North America where they are found in the

Mississippi River The Mississippi River is the second-longest river and chief river of the second-largest drainage system in North America, second only to the Hudson Bay drainage system. From its traditional source of Lake Itasca in northern Minnesota, it fl ...

basin and the drainages of the

Great Lakes The Great Lakes, also called the Great Lakes of North America, are a series of large interconnected freshwater lakes in the mid-east region of North America that connect to the Atlantic Ocean via the Saint Lawrence River. There are five lak ...

, Hudson Bay, the seaboards of the Atlantic and the

Gulf of Mexico The Gulf of Mexico ( es, Golfo de México) is an ocean basin and a marginal sea of the Atlantic Ocean, largely surrounded by the North American continent. It is bounded on the northeast, north and northwest by the Gulf Coast of the United ...

and the Pacific coast of Mexico.

Taxonomy

Fishbase recognises 5 genera as follows: * '' Ammocrypta''

Jordan Jordan ( ar, الأردن; tr. ' ), officially the Hashemite Kingdom of Jordan,; tr. ' is a country in Western Asia. It is situated at the crossroads of Asia, Africa, and Europe, within the Levant region, on the East Bank of the Jordan Rive ...

, 1877 * '' Crystallaria'' Jordan & Gilbert, 1885 * '' Etheostoma''

Rafinesque Constantine Samuel Rafinesque-Schmaltz (; October 22, 1783September 18, 1840) was a French 19th-century polymath born near Constantinople in the Ottoman Empire and self-educated in France. He traveled as a young man in the United States, ultimat ...

, 1817 * '' Nothonotus'' Putnam, 1863 * '' Percina'' Haldeman, 1842 However, Fishbase places '' Crystallaria'' within the subfamily Percinae while the 5th Edition of '' Fishes of the World'' regard it as a subgenus of ''Ammocrypta'' and ''Nothonotus'' as a subgenus of ''Etheostoma''.

References

{{Taxonbar, from = Q21225109 Percidae Ray-finned fish subfamilies