by charlesr1958 » Sun Mar 30, 2008 1:44 pm
Commensal - Living together and sharing food. Not something a snail is likely to do with other organisms and is unheard of.
With thousands of species, its hard to determine what species of "cowry" that you have, that and the photo is not all that good either...lol But.. the diets of most snails are unknown although the cowry groups are known more for their members being predators with few strict herbivores, many species are switch hitters, meaning that they will eat algae but if they come across something meaty, they can switch to eating that.
In the case of your snail, if they are found to always be on or around a specific coral type, they are most likely feeding upon the coral, either the coral's mucus or on the coral itself.
Chuck
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