The South American ampullarid Pomacea canaliculata is classified under the canaliculata complex. This is a groups af very closely related species which are very variable in size and appearance.

Shell: The shell of this apple snail species is globose and relatively heavy (especially in older snails). The 5 to 6 whorls are separated by a deep, indented suture (hence the name 'canaliculata' or 'channeled'). The shell opening (aperture) is large and oval to round. Males are known to have a rounder aperture than females. The umbilicus is large and deep. The overal shell shape is similar to that of Pomacea lineata, except the deeper sutures and more globose shape in canaliculata.
The size of these snails varies from 40 to 60 mm wide and 45 to 75 mm high depending on the conditions.
The colour varies completely yellow and green (cultivated forms) to brown with or without dark spiral bands (wild form). The shell growth of this species occurs mainly in spring and summer, while it stagnates in fall and winter.

Interactive 3D-models (Java):
- Pomacea canaliculata shell

Operculum: The operculum is moderately thick and corneous. The structure is concentric with the nucleus near the centre of the shell. The colour varies light (in young snails) to dark brown. The operculum can be retracted in the aperture (shell opening). 

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