Origin

Cipangopaludina chinensis, Chinese mystery snail is native to Eastern Russia and Asia. It is a large freshwater snail that may reach a shell length of up to 2.76 in. (7 cm). The shell is globose and has 6 to 7 whorls that are convex and have a clear suture. The colors of the shell are variable. Beginning with light coloration as a juvenile, later as an adult, their color darkens to olive green, greenish brown, brown or reddish brown. The inner coloration is white to pale blue and the lip is a black color. Adults are typically found on surfaces or partially buried under mud or silt, while juveniles are often found in crevices or under rocks.

Life Cycle

C. chinensis is a filter feeder of inorganic-organic debris and microalgae. They do not generally feed on plants. C. chinensis is viviparous. Females give birth to about 65 live offspring per year. C. chinensis males can be identified by the presence of a modified right tentacle that acts as a penis.

Distribution

C. chinensis has been introduced to North America, Hawaii, and the Netherlands. It has been stocked in waterways as a food for humans. It may have been dumped into waterways from aquariums or washed into waterways from ornamental ponds during flood events. It can also be transported by boats from one water body to another. C. chinensis prefers still or slow-moving rivers, streams, ponds, lakes, grass beds, rice paddies, roadside ditches or irrigation canals. They prefer freshwater bodies with soft, muddy or silty bottoms ranging from 1.5-15 ft. (0.5-4.5 m) in depth.

Control Efforts

Cipangopaludina chinensis can reach very high densities in a short period of time. It can survive for extended periods out of the water. C. chinensis has a thick outer shell and a hard operculum flap covering the shell opening that protects the snail from predators and unfavorable environmental conditions. These characteristics may allow the snail to be successful in invading new habitats. For example, allowing the snail to survive movement from one body of water to another while attached to the bottom of a boat. Very little is known about the negative effects on native snail species and ecosystems caused by B. chinensis in North America. More studies need to be done. Molluscicides have been shown to be effective. Always be sure to use only approved products and follow all instructions on the label.

Selected Images

Maps

Invasive Listing Sources

• Alberta Fisheries Act
• Idaho Invasive Species Act
• Invasive Species of Concern in Georgia
• Maryland Aquatic Nuisance Species Plan
• Maryland Invasive Species Council - Invasive Species of Concern in Maryland
• Minnesota DNR invasive species list
• New Jersey Invasive Species Strike Team 2017 Invasive Species List
• New York Regulated and Prohibited Invasive Species - Prohibited
• Ontario’s Invading Species Awareness Program Tracked Species List
• Pennsylvania's Field Guide to Aquatic Invasive Species
• West Virginia Invasive Species Strategic Plan and Volunteer Guidelines 2014
• Wisconsin's Invasive species rule – NR 40

References