An illustrated inventory of the sea slugs of New South Wales, Australia (Gastropoda: Heterobranchia)

Abstract

Although the Indo-Pacific is the global centre of diversity for the heterobranch sea slugs, their distribution remains, in many places, largely unknown. On the Australian east coast, their diversity decreases from approximately 1000 species in the northern Great Barrier Reef to fewer than 400 in Bass Strait. While occurrence records for some of the more populated sections of the coast are well known, data are patchy for more remote areas. Many species have very short lifecycles, so they can respond rapidly to changes in environmental conditions. The New South Wales coast is a recognised climate change hot-spot and southward shifts in distribution have already been documented for several species. However, thorough documentation of present distributions is an essential prerequisite for identifying further range extensions. While distribution data are available in the public realm, much is also held privately as photographic collections, diaries and logs. This paper consolidates the current occurrence data from both private and public sources as part of a broader study of sea slug distribution in south-eastern Australia and provides an inventory by region. A total of 382 species, 155 genera and 54 families is reported from the mainland coast of New South Wales.