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Pomacea maculata Perry, 1810

Overview

Origin

Pomacea maculata is a species of large, globular, freshwater snail native to tropical and sub-tropical South America. The thin fragile shells can reach up to 6 in. (15 cm) high and are higher than they are wide. Color can range from pale to darker olive green often with a faint dark band. Their name comes from the dark spots on the inside of their shell. P. maculata feeds on a large variety of aquatic plants in freshwater ponds, lakes, swamps and other wetlands. This species can easily be mistaken for other related snail species such as Pomacea canaliculata and Pomacea lineata. A recent study shows P. canaliculata and P. maculata can hybridize.

Life Cycle

In P. maculata the sexes are separate. Females lay clusters of bright pink eggs above the water line. They are attached to emergent vegetation or any dry emergent surface. Within 7-15 days the eggs usually hatch. Each mass of eggs can contain over 2000 eggs. Females can live up to 4 years and lay eggs as often as once a week during the growing season. Sexual maturity is reached when the snail reaches a certain size.

Distribution

P. maculata range from sub-tropical to tropical zones, but cannot tolerate temperatures below 50° F. They have been reported in Florida, Alabama, Arizona, Georgia, Texas, Louisiana, Mississippi, South Carolina and Puerto Rico. They are considered a serious crop pest of rice in Asia.

Control Efforts

Preventive measures that enforce strict quarantine should help reduce or prevent the spread or introduction of Pomacea to new areas. Handpicking can remove both snails and eggs. Other animals, including some birds, also eat these snails.

Resources

• Snail Busters Blog -

Selected Images

Maps

Invasive Listing Sources

• Everglades Cooperative Invasive Species Management Area
• Florida Invasive Species Partnership
• Invasive Species of Concern in Georgia
• Southwest Florida Cooperative Invasive Species Mgmt. Area