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The Tennessee dace (''Chrosomus tennesseensis'') is a species of ray-finned fish in the Cyprinidae family. It is found only in the United States; particularly in northeast Tennessee and southwest Virginia,〔 and parts of extreme northwest Georgia.〔http://www.cumberlandhcp.org/files/natureserve/Fish_10.23.08/Tennessee_Dace_10.13.08.pdf〕 Until recently, they were considered a subspecies of mountain redbelly dace.〔 They are commonly found in East Tennessee in spring fed first-order streams, often in silt and fine gravel pools, or undercut banks.〔Hamed, K. 2008. Life History Traits of the Tennessee Dace (''Phoxinus tennesseensis'') in Northeast Tennessee. ''The American Midland Naturalist''. 160: 289–299.〕 These streams usually do not exceed two meters in width.〔Etnier, D. 1993. ''Fishes of Tennessee''. 243–248.〕 Like all Tennessee species in the genus ''Chrosomus'', Tennessee dace have tiny scales and scaled breasts.〔 They usually have scarlet bellies, and are considered one of the most beautiful native fish in Tennessee.〔 Tennessee dace are considered nest associate spawners, using central stoneroller (''Campostoma anomalum'') and common creek chub (''Semotilus atromaculatus'') nests as spawning grounds.〔 There is evidence to suggest that the Tennessee dace can interbreed with the common creek chub.〔Eisenhour, D. 1997. Two New Intergeneric Hybrids Involving ''Semotilus atromaculatus'' and the Genus ''Phoxinus'' with Analysis of Additional ''Semotilus atromaculatus'': ''Phoxinus'' Hybrids. American Society of Ichthyologists and Herpetologists. 1: 204–209.〕 Spawning for Tennessee dace starts in April and extends into July.〔 Both males and females gain even more coloration during the breeding season.〔 Their diet is similar to that of other dace species, consisting mainly of attached algal growth.〔 Historically, Tennessee dace have only been found in 62 locations. Due to limited distribution and other factors, they are considered "in need of management" in Tennessee.〔Hamed, K. 2001. Distribution of the Tennessee dace, ''Phoxinus tennesseensis'', in northeast Tennessee. 80: 1–5.〕 Future threats include human development and climate change. ==Systematics and etymology== ''Chrosomus tennesseensis'' is a member of the same monophyletic group that contains ''Chrosomus cumberlandensis'' (mountain blackside dace), ''Chrosomus oreas'' (mountain redbelly dace) and ''Phoxinus saylori'' (laurel dace).〔 Until recently, the Tennessee dace was thought to be a variant of the mountain redbelly dace. However, morphological characteristics distinguish the two similar species. The Tennessee dace has a break in the dark lateral stripe that runs down the side of the body. Also, the Tennessee dace's eye pupil diameter is larger than the diameter of the dark spots above the lateral stripe,〔 while the spots of ''oreas'' are larger than the pupil.〔 The ''oreas'' is a more robust minnow with fewer scales in the lateral series.〔 The species name "''tennesseensis''" means "of Tennessee," which is a reference to the Tennessee River drainage encompassing much of its native range.〔 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「Tennessee dace」の詳細全文を読む スポンサード リンク
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