• ChesReport (current)
  • Marine Invasions Lab
  • Partner Portals
    Nemesis California Panama Galapagos Cocos Island NP JTMD
    Archived Projects
    Chesapeake
  • Browse Species
    Taxonomic Groups All Species
  • News
  • login
You are viewing an archived site. The Chesapeake Bay Introduced Species Database project ended in 2020 and the database is no longer receiving updates. Learn more…

Bellamya japonica

Mollusks-Gastropods

Japanese 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).

Description Taxonomy Invasion History Ecology Impacts References

Description

Bellamya japonica (Japanese Mystery Snail) is synonymized with B. chinensis by some authors and considered distinct by others (Clench and Fuller 1965; Jokinen 1982; Smith 2000). Clench and Fuller (1965) have identified B. japonica from Olahoma, Michigan, and Massachusetts. Smith (2000) presented anatomical arguments for applying the genus name Bellamya to these snails.

Taxonomy

Kingdom Phylum Class Order Family Genus
Animalia Mollusca Gastropoda Monotocardia Viviparidae Viviparus

Synonyms

Cipangopaludina japonica; Viviparus japonicus

Invasion History

Chesapeake Bay Status

First Record Population Range Introduction Residency Source Region Native Region Vectors
2007 Established Unknown Introduced egular Resident North America East Asia Ornamental(Pet Release)

History of Spread

The native and introduced ranges of Bellamya japonica (Japanese Mystery Snail) are poorly known because of taxonomic confusion. This snail is native to Japan, but it is uncertain whether B. chinensis occurs in Japan also, since these species were and are sometimes lumped (Clench and Fuller 1965; Jokinen 1982; Smith 2000). Museum collections (Academy of Natural Sciences of Philadelphia 2010; Museum of Comparative Zoology 2010) list specimens of B. chinensis from Japan. Smith (2000) describes morphological features separating the two species, and lists records for shells matiching the morphology of B. japonica. Records of this species appear to be more scattered than those of B. chinensis (Clench and Fuller 1965; Jokinen 1982; Smith 2000). It has, however, been reported from 15 states (USGS Nonidigenous Aquatic Species Program 2010), but not from the western US. Molecular studies may be needed to clarify the taxonomy and distribution of these large, conspicuous snails.

Great Lakes- Bellamya japonica was collected in Jackson MI, in the interior of Michigan's lower peninsula (Clench and Fuller 1965; Museum of Caomparative Zoology 2010). Bellamya japonica was reportedly introduced to Lake Erie in the 1940s as food for Channel Catfish (Ictalurus punctatus by local fishermen (Wolfert and Hiltunen 1968). The extent of its range in the Great Lakes, as elsewhere, is uncertain owing to confusion with B. chinensis..

East Coast- Specimens of B. japonica have been identified from the Concord River, Massachusetts (Clench and Fuller 1965), and two lakes in the interior of Connecticut (Smith 2000). Estuarine records are from the tidal fresh Connecticut River in Lyme, Connecticut (Smith 2000, undated) and from the tidal Potomac River, in Arlington, Virginia (2007, USGS Nonidigenous Aquatic Species Program 2010), and Gunston Cove (Kraus 2007). Previous records of Bellamya spp. from the Potomac have been identified as B. chinensis (Dundee 1974; US National Museum of Natural History collections). Based on an informal collection of shells (2000-2009), both species appear to be present in the Potomac.

Invasion Comments

None

Ecology

Environmental Tolerances

For SurvivalFor Reproduction
Minimum Maximum Minimum Maximum
Temperature (ºC)
Salinity (‰) 0.0 0.0
Oxygen None
pH
Salinity Range fresh-oligo

Age and Growth

Male Female
Minimum Adult Size (mm)
Typical Adult Size (mm) 52.0 52.0
Maximum Adult Size (mm) 65.0 65.0
Maximum Longevity (yrs)
Typical Longevity (yrs

Reproduction

Start Peak End
Reproductive Season
Typical Number of Young
Per Reproductive Event
Sexuality Mode(s)
Mode(s) of Asexual
Reproduction
Fertilization Type(s)
More than One Reproduction
Event per Year
Reproductive Startegy
Egg/Seed Form

Impacts

Economic Impacts in Chesapeake Bay

The abundance and distribution of Bellamya japonica (Chinese Mystery Snail) in the Chesapeake Bay and its watershed is unclear, and its economic impacts are unknown.

Economic Impacts Outside of Chesapeake Bay

Bellamya spp. are attractive and popular aquarium and fishpond snails as well as a food item once sold in Chinese markets in the United States (Jokinen 1982). These species are abundant in some regions and may have had local impacts on fisheries, either as food or by interfering with fishing. In Sandusky Bay, Lake Erie, 'fishermen often made seine hauls containing '2 tons' of snails' (Mills et al. 1993). However, they have been regarded as relatively benign invaders, with little known about their ecological impacts.

Ecological Impacts on Chesapeake Native Species

The abundance and distribution of Bellamya japonica (Japanese Mystery Snail) is unclear, and its impacts on native species are unknown, in Chesapeake Bay. Howver, in feld and laboratory studies in Wisconsin, the very similar B. chinensis was found to compete with native snails and affect the abundance of periphyton (Johnson et al. 2009).

Ecological Impacts on Other Chesapeake Non-Native Species

The abundance and distribution of Bellamya japonica (Chinese Mystery Snail) is unclear, and its impacts on other exotic species are unknown, in Chesapeake Bay and elsewhere. Competition with the similar snails B. chinensis and Viviparus georgianus are possible, as is hybridization with B. japonica.

References

2002-2024a Malacology Collection Search. http://clade.ansp.org/malacology/collections/

Clench, William J.; Fuller, Samuel L. H (1965) The genus Viviparus in North America, Occasional Papers on Mollusks, Museum of Comparative Zoology, Harvard University 2: 385-412

2006-2024 The freshwater gastropods of North America. http://www.fwgna.org

Fretter, Vera; Graham, Alastair (1962) British prosobranch molluscs: their functional anatomy and ecology, In: (Eds.) . , London. Pp.

2008-2021 Museum of Comparative Zoology Collections database- Malacology Collection. http://www.mcz.harvard.edu/collections/searchcollections.html

Johnson, Pieter T. J.; Olden, Julian D.; Solomon, Christopher T.; Vander Zanden, M. Jake (2009) Interactions among invaders: community and ecosystem effects of multiple invasive species in an experimental aquatic system, Oecologia 159: 161-170

Jokinen, Eileen H. (1982) Cipangopaludina chinensis (Gastropoda: Viviparidae) in North America, review and update, Nautilus 96: 89-95

Mills, Edward L.; Leach, Joseph H.; Carlton, James T.; Secor, Carol L. (1993) Exotic species in the Great Lakes: a history of biotic crises and anthropogenic introductions., Journal of Great Lakes Research 19: 1-54

Smith, Douglas G. (2000) Notes on the taxonomy of introduced Bellamya (Gastropoda: Viviparidae) species in northeastern North America., Nautilus 114: 31-37

Stanczykowska, Anna, Magnin, Etienne, Dumouchel, André (1971) Etude de trois populations de Viviparus malleatus (Reeve) de la region de Montreal. 1. Croissance, fecondite, biomasse, et production annuelle., Canadian Journal of Zoology 49: 1431-1441

2003-2024 Nonindigenous Aquatic Species Database. Gainesville, FL. http://nas.er.usgs.gov

Wolfert; David R.; Hiltunen, Jarl K. (1968) Distribution and abundance of the Japanese snail, Viviparus japonicus, and associated macrobenthos in Sandusky Bay, Ohio, Ohio Journal of Science 68: 32-40

Direct questions and comments to chesnemo@si.edu.

©