Sphaeriidae

Definition

Sphaeriidae (also known as pea clams or fingernail clams) is a family of small, freshwater bivalves in the order Sphaeriida and consist of 10 genera with 154 species. They are both hermaphrodites and ovoviviparous, giving birth to young that resemble miniature versions of adults [1].

Habitat

In North America, native species of sphaeriid have a broad distribution often ranging from the Atlantic to Pacific coast. Introduced species, such as Corbicula fluminea which originates from southeast Asia, also exhibit widespread distribution [2]. Many of these species occur in ephemeral ponds, small, variable flow streams, and profundal regions of lakes [3]. The preference of sphaeriids for these regions of low water flow, high silt, and large organic loads may reflect their lifestyle of sediment detritus feeding (Lopez and Holopainen, 1987). Species diversity in the genus Pisidium has also been shown to increase with decreasing particle size, indicating substrate preferences among sphaeriids possibly linked to their sediment feeding mechanisms (Kilgour and Mackie, 1998). Many sphaeriids are tolerant to air exposure which they achieve through unique emersion adaptations (Byne and McMahon, 1994).

References

1. Allaby, Michael. A Dictionary of Zoology, Oxford University Press, Incorporated, 2020. ProQuest Ebook Central, https://ebookcentral-proquest-com.gate.lib.buffalo.edu/lib/buffalo/detail.action?docID=6230105.
2. McMahon, Robert. (2000). Invasive characteristics of the freshwater bivalve Corbicula fulminea. Nonindigenous Freshwater Organisms: Vectors, Bilogy, and Impacts (2000), pp 315-343.
3. Burky, A. J. 1983. Physiological ecology of freshwater bivalves. in: Russell-Hunter, W. D., Ed. The Mollusca. Vol. 6 : Ecology. Academic Press, New York, pp. 281 – 327.
4. Lopez, G. R., Holopainen, I. J. 1987. Interstitial suspension-feeding by Pisidium sp. (Pisididae: Bivalvia): a new guild in the lentic benthos? American Malacological Bulletin 5:21 – 30..