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''Elimia virginica'', common names the Piedmont elimia or Virginia river snail, is a species of freshwater snail with an operculum, an aquatic gastropod mollusk in the family Pleuroceridae. == Shell description == ''Elimia virginica'' belongs to the family Pleuroceridae, a group of snails that have thick, elongated shells. The operculum in this species is proteinaceous, corneous, and paucispiral and is withdrawn when the snail is active. The shells are dextral and have a very high and narrow spire, with little space in the suture (the incisions between the whorls). This species has two distinct shell morphologies, one smooth and one lirate (i.e. finely lined or grooved).〔Smith, D. G. 1980. ''Goniobasis virginica (Gastropoda: Pleuroceridae) in the Connecticut River''. The Nautilus 94(2):50-54.〕 Specimens of this species often vary in coloration: in general, ''Elimia virginica'' is yellow to chestnut in hue, but it sometimes has 2 darker brown spiral bands.〔Peckarsky, B. L., P. R. Fraissinet, M. A. Penton and D. J. Conklin Jr. 1993. ''Freshwater Macroinvertebrates of Northeastern North America''. Cornell University Press, Ithaca, New York State. 442 pp.〕 Juveniles (snails with an aperture height of no more than 7 mm) display the banding more frequently than adults.〔 Shells of specimens of ''Elimia virginica'' from New York State and the Connecticut River range from 27 to 33 mm high, with an aperture height of 9–12 mm.〔 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「Elimia virginica」の詳細全文を読む スポンサード リンク
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