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The mimic shiner (''Notropis volucellus'') is a species of ray-finned fish in the genus ''Notropis''. The genus ''Notropis'' is commonly known as the Eastern Shiners. It is native to areas of Hudson Bay drainage, Great Lakes drainage, much of Mississippi River basin including areas of Tennessee, Virginia, North Carolina, and regions of the Gulf of Mexico extending from Mobile Bay to the drainage of Texas. However, this fish can be found in other places such as the Atlantic Coast drainage in Connecticut and Housatonic rivers. This genus is usually characterized by almost all having a complete lateral line, 8 dorsal fin rays, a premaxillae protactile, and a silvery or speckled peritoneum. As the common name indicates, this species is difficult to classify in the wild because it looks similar to many other shiners. In fact, some even hypothesize that this species is actually a complexity of many cryptic species.〔Etnier, D.A. and W.C. Starnes. 2001. The Fishes of Tennessee. Knoxville: University of Tennessee Press.〕 While this is the case, it is important to take more caution to not misidentify this species and to understand its impact on introduced areas. The diet of ''N. volucellus'' consists of some terrestrial insects, small crustaceans, and midge puppae and larvae.〔 Mimic shiners are reported to only live a total of three years, and are suspected to reach sexual maturity after one year.〔 In lakes, fish spawn in large schools located over beds of aquatic plants.〔Moyle, P.B. 1973. Ecological Segregation Among Three Species of Minnows (Cyprinidae) in a Minnesota Lake. Transactions of the American Fisheries Society 102(4):794–805.〕 When found in small streams ''N. volucellus'' are generally in clear pools over gravel substrate in moderate current but they can be seen along shorelines over gravel, sand, and mud substrates usually in slow to moderate current when found in large lakes.〔Hrabik, R. A. 1996. Taxonomic and distributional status of Notropis wickliffi in the Mississippi River drainage: a literature review. Long Term Resource Monitoring Program. Environmental Management Technical Center, Onalaska, Wisconsin, Special Report 96-S001: 15.〕 The diet of ''N. volucellus'' consists mostly of ''Daphnia'' in early spring and late fall while mostly small crustaceans, filamentous algae, and small invertebrates when ''Daphnia'' is not as abundant in the summer. This fish is suspected to have been introduced to many areas via bait bucket release.〔 Because negative impacts of the introduction of this species have not been documented and because this species is not listed as threatened,〔 there is not much immediate need for conservation efforts of this species. ==Distribution== Historically, this species has been mostly found in the southern Hudson Bay drainage, Great Lakes drainage, and much of Mississippi River basin except in the northern Great Plains region and is oddly missing from many of its tributaries. The mimic shiner is also in Atlantic Coast drainage in Connecticut, Virginia, North Carolina, and Housatonic rivers along with the region of the Gulf of Mexico extending from Mobile Bay to the drainage of Texas.〔 However, currently this species can also be found in Susquehanna River,〔Cooper, E.L. 1983. ''Fishes of Pennsylvania and the Northeastern United States''. University Park: The Pennsylvania State University Press.〕〔Malick, R.W. 1978. The mimic shiner, Notropis volucellus (Cope), in the Susquehanna River drainage of Pennsylvania. Proceedings of the Pennsylvania Academy of Science 52:199-200.〕 drainage in New York,〔Daniels, R.A., R. E. Morse, and B. R. Weatherwax. 2006. Fish, Conewango Creek, Allegheny River Drainage, New York, USA. Check List 2(1): 14-19 〕 Potomac River,〔Stauffer, J.R., Jr., J.M. Boltz, and L.R. White. 1994. The Fishes of West Virginia. PA: West Virginia Department of Natural Resources, Academy of Natural Sciences of Philadelphia.〕 East Branch of the Delaware River collected in 2002,〔Schmidt, R.E and R. Jacobs. 2005. The Mimic Shiner, Notropis volucellus (Cope), in Connecticut. Northeastern Naturalist 12(3): 20325–330.〕 Connecticut River drainage of Massachusetts,〔Schmidt, R.E. 1986. Zoogeography of the Northern Appalachians. pp. 137–159, In C.H. Hocutt and E.O. Wiley (Eds.). The Zoogeography of North American Freshwater Fishes. New York: John Wiley and Sons, Inc.〕〔Hartel, K.E., D.B. Halliwell, and A.E. Launer. 2002. Inland Fishes of Massachusetts. Lincoln: Massachusetts Audubon Society〕 low altitude, Connecticut regions such as Westhill Pond,〔 upper Nashua drainage of Massachusetts,〔 Housatonic River drainage in Massachusetts.〔〔Halliwell, D.B. 1979. 1979 Massachusetts fish list. Fauna of Massachusetts Series #4, Massachusetts Division of Fish and Wildlife, Publication #11,348-15-1,000- 5-79-CR.〕 It is suspected that the disappearance of mimic shiners in some areas may be due to a change in hydraulic regimes due to fragmentation of landscapes along with urbanization and development. Due to fragmentation of the landscape near or around riverine ecosystems, there is less available vegetation along these areas. With less vegetation, a faster flow of water pours into streams and rivers and possibly causes erosion to its banks. This influx of water and higher velocity of flow could have negative impacts on this species that lives in areas that has a relatively slow to moderate current.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Mimic shiner」の詳細全文を読む スポンサード リンク
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