Chinese Mystery Snail, Cipangopaludina chinensis malleatus

Scientific Name:
Cipangopaludina Chinensis Malleatus

Common Names:
Chinese Mystery Snail, Japanese Mystery Snail, Black Japanese Trapdoor Snail, Asian Apple Snail, Japanese Trapdoor Snail, Rice Snail and Oriental Mystery Snail


Research Summary: Maya P. and Chris B.

Maya: The Chinese mystery snail is a species people don’t know a lot about. These small animals have traveled across the world from China and Japan to the United States. A lot of information is unsure and on certain topics, like control, it was very hard to find any information.

One of the most important things I discovered about this species is that these snails can’t be chemically controlled because they can close their operculum (or trap door on their shell) until water conditions are better. This means that if you try to poison them, all you end up doing is hurting the other organisms living in that habitat.  The most surprising thing that I learned about my snail is that they are actually eaten my humans. We are their natural predators!

Chris: The Chinese mystery snail is a invasive species found across America. It is very hard to control the Chinese Mystery snail. They have been invading our native snails and taking over there space. The Chinese Mystery Snail has been introduced to America by Via buckets. The most amazing thing about the Chinese Mystery Snail is that they can be gold, black, and blue.

Identifying Characteristics

  • Can grow up to 65 millimeters. 
  • Large, smooth, olive green shell.
  • No color bands on shell.
  • White and blue inner shell.
  • 6-7 convex whorls on top of the snail's shell.
  • Black round or oval outer lip.
  • Has a operculum (trapdoor) on shell.


Taxonomy of Species

   Scientific Classification
 What That Classification Means
 Kingdom  Animalia  Is a eukaryotic, many celled organism that can move and obtain food
 from other organisms. 
 Phylum  Mollusca  Is an organism with coelom (or a case) mesoderm filled with fluid. They
 also have a strong shell and a soft body. 
 Class  Gastropodo
 A class of mollusks typically having a one piece coiled shell and flattened
 muscular foot with head baring stalked eves.
 Order  Architaenoglossa  Snails which have gills. They also have an operculum, which means a
 little door on their shell; they live primarily on land and fresh water.
 Family  Viviparidae  Animals that have live babies. (As opposed to eggs.)
 Genus  Cipangopaludina  The Chinese Mystery Snail, Japanese Mystery Snail, Black Snail, or
 Trapdoor Snail.
 Species Chinensis
 Most likely from China. Or Chinese.

Similar species include:

Location and Movement
Origin/ Native Range  Native to Burma, Thailand, South Vietnam, China, Korea, Japan, the Philippines, and Java. 


  • Chinese mystery snails were first brought to the United States in 1892 as an imported food source to San Francisco for Asian food markets. 
  • The snails were released in San Francisco and first found on the eastern coast in Boston, Massachusetts in 1915.
Spread of Species
  • They were released because people wanted a local supply.
  • Can be transported by getting tangled in plants attached to boat propellers.  It was also introduced by releases from the aquarium industry.  
  • Transported, as adults or tiny juveniles, via bait buckets and water holding areas on boats.
Where is it now invasive?
  • The Chinese Mystery Snail is invasive to 26 states in the U.S; including Maine, Massachusetts, Michigan, Indiana, Ohio and California. 
  • They also can be found in some of the Great Lakes.

Is this species in Maine?

Where has it been identified?

  • Found in over 35 different towns.
  • Mostly in southeastern Maine but you can find a few in northern Maine.
  • It has been found in these water bodies:  Alamoosook L., Annabessacook L., Anasagunticook L., Branch L., Damariscotta L., Highland (duck) L., Island P., Andrews L., Auburn L., Pennesseewassee L., Pleasant L., Sabattus P., Sand P., (Tacoma LKS), Sand P., Sebago L., Thomas P., Tricky P., and Little Wilson Pond.
How was this species introduced?
  • See above Spread of Species.

Natural Environment
  • Prefers to live near the shores of lakes, ponds or rivers.
  • Lives underwater half buried in sediment.
  • Lives in irrigation ditches, and roadside ditches.
Climate and Temperature Range
  • Thrives in 34- 80° Fahrenheit. 

Ecological Interactions Omnivore.

Obtaining food

  • Consume a lot of algae and diatoms. 
  • They also eat zooplankton and phytoplankton.
Consumed By
Humans, crows, and crabs.

  • Has made it into lakes all over the country and is upsetting food chains by competing and stealing food and space from native populations.
  • They reproduce quickly and form very dense populations.
  • It brings harmful diseases via parasites that can be passed to humans.
  • Clogs up screen of water intake pipes.
Economic  Upsetting fishing. An example of this is fishermen fishing for sein (a species of fish) in Sandusky
 Bay, Ohio hauled up "two tons of snails". 

  • Using methods used for other snails such as predators like puffers, loaches, chichlids, and other fish, as well as snail eating turtles.  Some, however, may effect the natural environment in negative ways. Loaches, for example, may get aggressive with native fish populations.
Mechanical/Manual  You can control the Chinese mystery snail by using hand and fishing nets. 
  • Missouri outlawed possession and sale of these snails.   
  • Prevention is important to controlling these snails.
  • Identifying snails, watching what you dump into the ocean, and cleaning equipment are just some of the precautions being used.
  • Most chemical control doesn't work on these snails. Some copper compounds are sold as snail killers. However these kill any and almost all snails and can do more harm than good.
  • When water conditions are unfavorable (poisonous) they can shut their operculum and survive until water conditions are better.

Interesting Facts
    • Males live an average of 3-4 years while females live an average of 5 years.
    • When Chinese mystery snails die, they omit an unpleasent odor.