Purple Gibbus Snail (Gibbus lyonetianus)
This species was described in 1780.
The Purple Gibbus Snail was endemic to the island of Mauritius, it had a conspicuous, strangely compressed shell and probably was a predatory species.
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It appears to have been a quite colorful species.:
“The sole of the foot in this species is yellow; the anterior part of the upper surface varies from reddish claret to purple, and the posterior is yellow, dotted with minute purplish spots; the tentacles are dull purple.” [1]
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References:
[1] Geoffrey Nevill: Notes on some of the species of land Mollusca inhabiting Mauritius and the Seychelles. Proceedings of the Zoological Society of London 257-261. 1868
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(public domain)
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edited: 06.11.2017