Arnhemtrachia ramingining: a new genus and species of land snail from Arnhem Land, Australia (Stylommatophora: Camaenidae)

Abstract

The new, monotypic camaenid genus Arnhemtrachia is described for the new species Arnhemtrachia ramingining from Ramingining, Arnhem Land, Northern Territory, Australia with additional records from the Gove Peninsula in eastern Arnhem Land. This camaenid is characterised by a combination of distinct morphological features, such as a small, discoidal, keeled shell with regular axial ribs, open umbilicus and simple, rounded aperture as well as a reproductive system with a long epiphallus possessing a long flagellum and absence of a penial sheath, with a flap on the penial wall which transverses longitudinal pilasters, and a long, simple bursa copulatrix. Based on comparative morphology, Arnhemtrachia reveals affinities with Trozena morata Iredale, 1838 from NE Queensland.

Keywords:

• Helicoidea
• Pulmonata
• taxonomy
• Northern Territory
• Australian Monsoon Tropics
• morphology
• anatomy

Acknowledgements

This work has been made possible through financial support from the Australian Government (ABRS grants RF210-05 to FK). Special thanks are due to Morgan Laudine (Newcastle) for producing illustrations of genitalia, and to Sue Lindsay (AM) for conducting the SEM work. Two reviewers, Gary Barker and John Stanisic, and Winston Ponder, provided helpful comments on the manuscript of this paper, which are most gratefully acknowledged.