FWGNA > Species Accounts > Viviparidae > Lioplax subcarinata
Lioplax subcarinata (Say 1817)
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> Habitat & Distribution

The range of Lioplax subcarinata historically extended through Atlantic drainages from South Carolina to the Hudson River (Clench & Turner 1955, Clench 1965, Vail 1979).  Jokinen (1992) reported that this species seems to have been extirpated from New York, however, and we ourselves are aware of only a single modern record anywhere north of the Potomac.  Our surveys have found populations of L. subcarinata distributed in patchy fashion through coastal plain portions of the Lynches, Waccamaw, Lower Neuse, Tar/Pamlico, and Chowan Rivers.  There are older records from the Potomac (Clench & Turner 1955).  Our limited observations suggest that the animal burrows in flocculent silt.  FWGNA incidence rank I-4. click map to view larger

> Ecology & Life History

The ecological literature contains few studies specifically addressing Lioplax. But judging from its biological similarity to Campeloma, one might infer that Lioplax has the ability to filter feed or suspension feed on fine organic particles. Unlike Campeloma, however, there is no evidence of parthenogenesis in Lioplax, as far as we are aware (Vail 1977). Vail (1978) reported a perennial, iteroparous life cycle for the population of Lioplax pilsbryi she studied in north Florida (Hi of Dillon 2000), animals requiring two years to mature.

> Taxonomy & Systematics

Six nominal species of Lioplax are listed in Burch, but only L. subcarinata occurs in Atlantic drainages. The genus attracted considerable attention in the mid -20th century, first from Clench (Clench & Turner 1955, Clench 1962) then from V. A. Vail, and has subsequently enjoyed a period of taxonomic stability. Vail (1977) has published a nice set of anatomical observations on her Lioplax pilsbryi population.

> Supplementary Resources [PDF]

> Essays

  • I published an essay reporting the rediscovery of Lioplax in South Carolina on 26Aug04. Photos of the habitat and the living animal are available from that page.
  • The sad fate of the Waccamaw population of Lioplax subcarinata was mentioned in my post of 16July10, "Crisis at Lake Waccamaw."

> References

Burch, J. B. (1989)  North American Freshwater Snails.  Malacological Publications, Hamburg, MI.  365 pp.
Dillon, R. T., Jr. (2000)
The Ecology of Freshwater Molluscs. Cambridge University Press, United Kingdom. 509 pp.
Clench, W. (1962) New records of the genus Lioplax. Occas. Pprs. on Mollusks, Mus. Comp. Zool. Harvard, 2(27): 288.
Clench, W. (1965) Supplement to the North American genus Lioplax. Occas. Pprs. on Mollusks, Mus. Comp. Zool. Harvard, 2(34): 426.
Clench, W. & Turner, R. D. (1955)
The North American genus Lioplax in the family Viviparidae. Occas. Pprs. on Mollusks, Mus. Comp. Zool. Harvard 2(19): 1 – 20.
Jokinen, E. (1992) The freshwater snails (Mollusca: Gastropoda) of New York State. New York State Museum Bulletin 482: 1-112.
Vail, V.A. (1977) Comparative reproductive anatomy of 3 viviparid gastropods. Malacologia 16: 519-520.
Vail, V.A. (1978) Seasonal reproductive patterns in 3 viviparid gastropods.  Malacologia 17: 73-97.
Vail, V.A. (1979)
A preliminary revision of Florida Lioplax (Gastropoda: Viviparidae) with a description of Lioplax talquinensis sp. nov. Malacol. Rev. 12: 87 – 88.