Chesapeake Bay Introduced Species Database

Bellamya chinensis

Common name(s):
Chinese Mystery Snail
What?s so mysterious about mystery snails? Mystery snails are the largest freshwater snails in the region (max 3 inches). They have spiral shells with a door (operculum) used to seal themselves inside. Unlike most freshwater snails, they give birth to live young. The sudden appearance of baby snails surprised agriculturalists, hence the name mystery snails. The identification of these snails has been confused many times and there was debate about whether or not Japanese Mystery Snails (Bellamya japonica) and Chinese Mystery Snails (Bellamya chinensis) are actually the same species. A recent study shows that they are different species, but here they are lumped together. Mystery snails are native to Asia where they are a common food item. In 1892 they were imported to Chinese markets in San Francisco and by 1911 had established around San Jose and San Francisco. Over time the snails moved from the Chinese food markets into the aquarium trade and were transported across the country for use in aquarium and ornamental ponds. They are now widespread in ponds, lakes, and reservoirs from California to British Columbia and Florida to Quebec. The first reports of the snails in the Chesapeake region were in the 1960s when they were found in the Susquehanna and Potomac Rivers. They are now common in the Potomac and Susquehanna, but elsewhere in Chesapeake their abundance and distribution is unknown. Their shells are large and conspicuous, so let us know if you find them in a new river (443-482-2467).
Image courtesy of Oregon Department of Fish & Wildlife.


Bellamya chinensis


Paludina malleata; Viviparus malleatus; Viviparus chinensis malleatus; Cipangopaludina chinensis; Cipangopaludina chinensis malleata

Potentially Misidentified As:

Viviparus georgianus; Cipangopaludina japonica

Common Names:

Asian Mystery Snail; Chinese Mystery Snail; Chinese Apple Snail; Asian Apple Snail


Potentially Misidentified Species - B. japonica (Japanese Mystery Snail) is synonymized by some authors and considered distinct by others (Clench and Fuller 1965; Jokinen 1982). Clench and Fuller (1965) have identified B. japonica from OK, MI, and MA. V. georgianus is native to the Mississippi Basin and southeast United States and introduced in the Potomac (Clench 1962). Smith (2000) presented anatomical arguments for applying the genus name Bellamya to these snails, and described differences between the two species Based on these descriptions, and an informal collection of shells, both species are present in the Chesapeake Bay watershed.

This data was last modified on Wednesday, July 17th, 2013.
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