This species is locally abundant throughout its native distribution (NatureServe 2009), and occasionally reaches densities of 15,000 to 28,000 individuals per m2 in introduced parts of its range (Verween et al. 2009).
This species is unlikely to be impacted by any major threats, although because of its bio-fouling abilities (causing huge economic damage to industry) it is targeted by biocides and other control measures (Global Invasive Species Database 2005).
Global Range: (20,000-200,000 square km (about 8000-80,000 square miles)) This species is native from Chesapeake Bay southward through the Gulf of Mexico but was introduced into the Hudson River, New York, as early as 1937 and later to the lower Charles River, Massachusetts, according to Rehder (1937), Jacobson (1953) and Carlton (1992). Benson et al. (2001) cite invasions in Alabama, Florida, Kentucky, and Tennessee.
This species is highly adaptible has broad ecological tolerances, inhabiting freshwater through to oligohaline habitats. It has spread from its native range via ship ballast water and through canals (Therriault et al. 2004). It can also be found in coastal and estuarine habitats, riparian zones and wetlands, even occurring in cooling water conduits of power stations (Global Invasive Species Database 2005).
It can look very similar to the zebra mussel, with similar stripes, but it can be distinguished from it by an apophysis or projection on the inside of the shell near the umbo. Shell length ranges between <1 and 2 cm, with an average length of 1 cm.
Mytilopsis leucophaeata is found in brackish water, at salinities ranging from 0.5 psu to about 12 psu, although its upper salinity limit is usually about 5–6 psu. It attaches to hard substrates, including oyster and true mussel shells and cages for them, rocks, boats, and pilings, and also to ropes.
^ abHeiler, K. C. M.; Nahavandi, N.; Albrecht, C. (2010). "A new invasion into an ancient lake — The invasion history of the dreissenid mussel Mytilopsis leucophaeata (Conrad, 1831) and its first record in the Caspian Sea". Malacologia 53: 185–192. doi:10.4002/040.053.0112.