Hebetancylus excentricus

Hebetancylus excentricus

Secure  (NatureServe)[1]
Scientific classification
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H. excentricus
Binomial name
Hebetancylus excentricus
(Morelet, 1851)

Hebetancylus excentricus, the excentric ancylid, is a species of small, freshwater, air-breathing limpet, an aquatic pulmonate gastropod mollusc or micromollusc in the family Planorbidae, the ram's horn snails and their allies.[2][3]

Geographic distribution

H. excentricus is widely distributed across North and Central America and the Caribbean.[1] The main area of its North American range extends from Florida to Texas, but it has also been reported from scattered ponds and river backwaters along the length of the southern Atlantic Coastal Plain as far north as North Carolina. This pattern of contagious distribution suggests that the species is possibly being dispersed through the air by migratory waterfowl.[4][5]

Habitat and ecology

H. excentricus usually occurs on rocks in fast-flowing streams and occasionally on rocks and rooted aquatic vegetation in lakes and the impounded backwaters of rivers and streams.[6] It also occurs on submerged sticks, logs, and large items of organic debris.[4]

Annual, bi- and trivoltine life cycles have been reported in Louisiana[4] and Texas[6] populations of H. excentricus; however, this increased number of generations occurs without an increase in population growth rates.[6]

References

  1. ^ a b "Hebetancylus excentricus - (Morelet, 1851)". NatureServe. Retrieved 27 June 2014.
  2. ^ Roskov Y.; Kunze T.; Orrell T.; Abucay L.; Paglinawan L.; Culham A.; Bailly N.; Kirk P.; Bourgoin T.; Baillargeon G.; Decock W.; De Wever A.; Didžiulis V., eds. (2014). "Hebetancylus excentricus Morelet 1851". Species 2000 & ITIS Catalogue of Life, 2014 Annual Checklist. Species 2000: Naturalis, Leiden, the Netherlands. Retrieved 29 June 2014.
  3. ^ Bouchet, P. (2014). "Hebetancylus excentricus (Morelet, 1851)". WoRMS. World Register of Marine Species. Retrieved 29 June 2014.
  4. ^ a b c Dillon, R. T. Jr.; Watson, B.T.; Stewart, T. W. & Reeves, W. K. (2006). "Hebetancylus excentricus (Morelet 1851)". The freshwater gastropods of North America. Retrieved 29 June 2014.
  5. ^ Dillon, R. T. (2005). "Aerial Dispersal of Freshwater Gastropods". The Blog of the FWGNA Project. Retrieved 29 June 2014.
  6. ^ a b c McMahon, R. F. (1976). "Growth, reproduction and life cycle in six Texan populations of two species of fresh-water limpets". American Midland Naturalist. 95 (1). University of Notre Dame: 174–185. doi:10.2307/2424243. JSTOR 2424243.