The grotto sculpin (''Cottus specus)'' 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 h ...

belonging to 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 ...

Cottidae The Cottidae are a family of fish in the superfamily Cottoidea, the sculpins. It is the largest sculpin family, with about 275 species in 70 genera.Kane, E. A. and T. E. Higham. (2012)Life in the flow lane: differences in pectoral fin morphology ...

, the typical sculpins. It is found in the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., federal district, five ma ...

where it only inhabits the Bois Brule drainage (although not recorded from the main stream itself) in

Perry County Perry County may refer to: United States *Perry County, Alabama *Perry County, Arkansas *Perry County, Illinois *Perry County, Indiana *Perry County, Kentucky *Perry County, Mississippi *Perry County, Missouri *Perry County, Ohio *Perry Coun ...

of southeastern

Missouri Missouri is a U.S. state, state in the Midwestern United States, Midwestern region of the United States. Ranking List of U.S. states and territories by area, 21st in land area, it is bordered by eight states (tied for the most with Tennessee ...

. It reaches a maximum

standard length Fish measurement is the measuring of individual fish and various parts of their anatomies. These data are used in many areas of ichthyology, including taxonomy and fisheries biology. Overall length * Standard length (SL) is the length of a fish ...

of . This

cavefish Cavefish or cave fish is a generic term for fresh and brackish water fish adapted to life in caves and other underground habitats. Related terms are subterranean fish, troglomorphic fish, troglobitic fish, stygobitic fish, phreatic fish and h ...

lives in underground streams and their resurgences. It was formerly confused with the more widespread '' C. carolinae'', but can be separated by (among others) its smaller eyes and various degrees of reduced pigmentation. It is one of only three known cases of

troglomorphism Troglomorphism is the morphological adaptation of an animal to living in the constant darkness of caves, characterised by features such as loss of pigment, reduced eyesight or blindness, and frequently with attenuated bodies and/or appendages. The ...

in the sculpin family, the others also involving U.S. '' Cottus'' ('' C. bairdi— cognatus'' species complex in

Pennsylvania Pennsylvania (; (Pennsylvania Dutch: )), officially the Commonwealth of Pennsylvania, is a state spanning the Mid-Atlantic, Northeastern, Appalachian, and Great Lakes regions of the United States. It borders Delaware to its southeast, Ma ...

, and ''C. carolinae'' in

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 ...

References

{{Taxonbar, from=Q29385875 Cave fish Cottus (fish) Fish described in 2013 ESA endangered species Perry County, Missouri