> Habitat & Distribution

This is primarily a species of the American interior, widespread in the Mobile, Mississippi, and other Gulf drainages from Texas to Minnesota (Clench & Fuller 1965).  Our surveys have found V. intertextus populations not uncommon in the lowest, slowest sections of the main Ohio and Wabash Rivers.  We are aware of but a single population in the Tennessee/Cumberland drainage, a 1991 museum record from Wheeler Lake in North Alabama.

The occurrence of V. intertextus in Atlantic drainages, from Georgia to southern North Carolina, seems peripheral.  Atlantic-drainage populations typically inhabit swamps and slow-moving rivers of the Coastal Plain, often in shallow, isolated, or even ephemeral habitats.  Although the waters of such environments typically carry some dark stain, it is our impression that they are not excessively acidic.  FWGNA incidence rank I-4.

> Ecology & Life History

Cook (1949) has documented filter feeding (or perhaps “ciliary feeding” is more descriptive) in the European V. viviparus.  The sedentary, burrowing behaviour reported for the European animals closely matches that displayed by V. intertextus in swamps of the US Interior and Coastal Plain.  Nothing is known regarding the life cycle of V. intertextus.  Some concern has been expressed regarding the conservation status in South Carolina (Fuller et al. 1976), but the general inhospitality of its preferred environment (mosquito and alligator-infested swamps) makes undercollection a distinct possibility.

> Taxonomy & Systematics

Viviparus intertextus is taxonomically well-characterized and systematically stable (Clench & Fuller 1965).

> Maps and Supplementary Resources

• Viviparus distribution in the drainage of The Ohio (2019)
• Viviparus distribution in Atlantic drainages (2023)
• Viviparus in the Tennessee/Cumberland (2022)

> References

Clench, W. (1962)  A catalogue of the Viviparidae of North America with notes on the distribution of Viviparus georgianus, Lea. Occas. Pprs. on Mollusks, Mus. Comp. Zool. Harvard, 2, 261-87.  
Clench, W. & Fuller, S. (1965)  The genus Viviparus in North America. Occas. Pprs. on Mollusks, Mus. Comp. Zool. Harvard, 2, 385-412.  
Cook, P. (1949)  A ciliary feeding mechanism in Viviparus viviparus (L).  Proc. Malacol. Soc. Lond. 27: 265-271.  
Fuller, S. L. H., F. W. Grimm, T. L. Laavy, H. J. Porter, & A. H. Shoemaker (1976)  Status Report: Fresh Water and Terrestrial Mollusks.  Pp 55 – 59 in Proceedings of the First South Carolina Endangered Species Symposium (D. M. Forsythe & W. B. Ezell, eds.).