Chinese Mystery Snail

Species of the genus Cipangopaludina can be identified by their relatively large globose shells and concentrically marked opercula. The shell is conical and thin but solid, with a sharp apex and relatively higher spire and distant body whorl. This species has a small and round umbilicus and the spire is produced at an angle of 65–80°. Cipangopaludina chinensis exhibits light coloration as a juvenile and olive green, greenish brown, brown or reddish brown pigmentation as an adult. The inner coloration is white to pale blue.

The surface of the shell is smooth with clear growth lines. The shell has 6.0–7.0 whorls.

Though native to East Asia from the tropics of Indochina to northern China, this species has established itself in North America.

The native range is from Southeast Asia to East Asia. This species is widely distributed in China including the Chinese Loess Plateau.

Cipangopaludina chinensis feeds non-selectively on organic and inorganic bottom material as well as benthic and epiphytic algae, mostly by scraping, but diatoms are probably the most nutritious food it ingests at sites in eastern North America.

This species is primarily an algae eater in an aquarium context. These snails are popular in freshwater aquariums because they do not eat fish eggs or plants, they do not overpopulate the aquarium, and they close up if there is a water problem, giving people an indication that something is wrong a few weeks before the fish die.

This species prefers freshwater lakes with soft, muddy or silty bottoms, reservoirs, slow-moving freshwater rivers, streams, paddy fields, and ponds with aquatic grass, creeping at the bottom of the water or on aquatic grasses. It prefers lentic water bodies with silt, sand, and mud substrate in eastern North America, although it can survive in slower regions of streams as well. It can tolerate conditions in stagnant waters near septic tanks.

This species has been found in waters in eastern North America with pH 6.5–8.4, calcium concentration of 5–97 ppm, magnesium concentration of 13–31 ppm, oxygen concentration of 7–11 ppm, depths of 0.2–7m, conductivity of 63–400 μmhos/cm, and sodium concentration of 2–49 ppm.

The optimal water temperature for it to grow and develop is between 20 and 28 °C. It will hibernate while water temperature is lower than 10-15 °C or higher than 30 °C.

Reproduction is initiated sexually. This species is ovoviviparous. Females live up to 5 years, while males live up to 3, occasionally 4 years. Female fecundity is usually greater than 169 young in a lifetime, and may reach up to 102 for any given brood. All females generally contain embryos from May to August and young are born from June through October in eastern North America in shallow water, then females begin migrating to deeper water for the winter in the fall. Females bear more young in their 4th and 5th years than in other years.

This species constitutes one of the three predominant freshwater snails found in Chinese markets. This snail is extensively used as part of the human diet in most places in China because the meat of the snail is considered delicious, being rich in nutrition, with high protein and low fat content. Moreover, in China it is also used as a medicine for treatment of digestive disease.

Its shells are abundant in archaeological sites in the Guanzhong Basin of Northwestern China from the Mid-Late Neolithic age. These are remains of prehistoric meals. The flesh was eaten mainly as subsidiary food.

This snail is also one of the rice field snail species traditionally eaten in Thailand.