genus includes several hundred fossil forms, mostly Paleozoic.
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It is one of the oldest gastropod genera, commencing in the Cambrian.
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After taking a considerable hit during the Cretaceous–Paleogene extinction event, they have been restricted to deeper waters through the Cenozoic.
The group took quite a hit at the Cretaceous–Paleogene boundary (K–T boundary), with only the Pleurotomariidae surviving the Cretaceous–Paleogene extinction event – and then only in deep waters.