The South American ampullarid Pomacea insularum 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 thick (especially in older snails) with a low spire. The 4 to 5 whorls are separated by a sligthly indented suture. The shell opening (aperture) is large and oval to round, sometimes ligthly reflected. The umbilicus is large and deep. The size of these shell varies from 25 to 40 mm wide and 30 to 47 mm high depending on the conditions.
The shell is yellow-brown to yelow-live in colour with a dark banding pattern.
Operculum: The operculum is moderately thick and corneous. The structure is concentric with the nucleus near the centre of the shell. The operculum can be retracted in the aperture (shell opening). 
Body: The body has a grey-brownish colour with dark pigment spots.
Pomacea insularum.
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Pomacea insularum.
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Pomacea insularum.
(picture not licenced under creative commons)
Pomacea insularum.
(picture not licenced under creative commons)
Pomacea insularum ...

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