Taiwanassiminea phantasma n. sp.: a terrestrial assimineid (Caenogastropoda: Truncatelloidea) from Middle Osborn Island, Kimberley, Western Australia

Abstract

A new terrestrial assimineid gastropod, Taiwanassiminea phantasma n. sp. (Truncatelloidea: Assimineidae), is described. Taiwanassiminea phantasma is characterised by its translucent, conical shell with deeply impressed sutures, spiral groove surrounding a wide umbilicus, relative lack of pigmentation and long distal penial papilla. The species differs from most assimineids in having a subcircular aperture and an operculum with a central nucleus. Taiwanassiminea phantasma has anatomical similarities to other members of Taiwanassiminea, and this relationship is supported by a partial cytochrome oxidase I mitochondrial analysis. Taiwanassiminea phantasma lives in leaf litter in vine thickets on Middle Osborn Island in northern Kimberley, Western Australia, where it is possibly endemic. No terrestrial assimineid is otherwise known from mainland Australia or its adjacent islands, including Tasmania.

http://zoobank.org/urn:lsid:zoobank.org:pub:A14ACAAE-4BAD-402D-9F9D-3BC9D928411A

Keywords:

• Assimineidae
• land snail
• Taiwanassiminea

Acknowledgements

Thanks are due to Winston Ponder for helpful and constructive comments, Alison Miller for preparing and mounting radula, and Sue Lindsay for scanning electron microscopy laboratory assistance. Vince Kessner and Roy Teale are thanked for their collection efforts, Michael Shea, Frank Köhler and Francesco Criscione for their input on the Kimberley land snail fauna, and Corey Whisson and the Western Australian Museum for kindly lending specimens. We are grateful to Des Beechey for photographic advice, and to Mandy Reid, Janet Waterhouse and Alison Miller for their assistance with collection and database materials. Furthermore, we thank two reviewers for providing comments that have improved the manuscript. Finally, we wish to acknowledge the Australian Biological Resource Study for awarding a grant to one of us (AH).