The oldest fossil Hydrocenidae found in mid-Cretaceous Burmese amber (Gastropoda: Cycloneritida)

摘要

A newly-discovered fossil gastropod belonging to the family Hydrocenidae is studied using classic light microscopy and modern micro-CT scans with 3D computer reconstructions. ?Hydrocena praecursor sp. nov. is the oldest known member of the Hydrocenidae and the only Mesozoic representative of the family in Asia. The present finding supports previous assumptions of a Mesozoic origin of the family and indicates that Hydrocenidae have become fully terrestrial at least by the mid-Cretaceous. Moreover, our discovery implies a much wider fossil distribution of Hydrocenidae than previously assumed.