New Tudivasum Rosenberg & Petit, 1987 (Mollusca: Vasidae) from the Coral Sea, Australia

A new Tudivasum endemic to the Saumarez Reef system of the Queensland coast is described. Tudivasum gracelumwanae is a shallow water lagoon and reef dwelling mollusc that can be differentiated from others within that genus by its golden-coloured aperture and distinctively flared posterior columella. The species is described based on morphological differences and compared to others in the genus, both in terms of their morphology and distributions. The recognition of this new species further enables an understanding of the relationships between other Tudivasum species to be explored with reference points for the known biographically and morphologically distinctive taxa.