Shell Description
These gastropods are large, with shells up to 9 cm across (Powelliphanta superba prouseorum).
Their striking delicately patterned shells come in an array of shades, from brown or red to yellow or black. The structure of these shells is very delicate, with a very thin layer of calcium carbonate, covered by a thicker chitinous outer layer. These snails need moist surroundings, otherwise the outer layer (periostracum) dries, shrinks and cracks. This happens often in museum shells of this genus which are stored dry; when they dry too much, the shell shatters explosively into fairly small pieces.
Read more about this topic: Powelliphanta
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