University of Wollongong Research Online University of Wollongong Thesis Collection University of Wollongong Thesis Collections 2006 Systematics of the Australasian Lymnaeidae Louise Puslednik University of Wollongong Recommended Citation Puslednik, Louise, Systematics of the Australasian Lymnaeidae, PhD thesis, School of Biological Sciences, University of Wollongong, 2006. http://ro.uow.edu.au/theses/815 Research Online is the open access institutional repository for the University of Wollongong. For further information contact the UOW Library: [email protected] Systematics of the Australasian Lymnaeidae A thesis submitted in fulfilment of the requirements for the degree DOCTOR OF PHILOSOPHY from UNIVERSITY OF WOLLONGONG by Louise Puslednik SCHOOL OF BIOLOGICAL SCIENCES 2006 i CERTIFICATION I, Louise Puslednik, declare that this thesis, is submitted in fulfilment of the requirements for the award of Doctor of Philosophy, in the School of Biological Sciences, University of Wollongong, is wholly my own work unless otherwise referenced or acknowledged. The document has not been submitted for qualifications at any other academic institution. ii Abstract The Lymnaeidae Rafinesque, 1815 are one of the most widespread groups of freshwater snails, however, they are characterised by a long and confused systematic history largely due to problems associated with shell plasticity. Recent molecular studies that have utilised DNA sequences have failed to adequately represent the Australasian lymnaeids. The aim of this study was to understand the systematics of the Australasian Lymnaeidae, using 16S and ITS-2 sequences in tandem with a anatomical and shell studies. The native Australian and New Zealand lymnaeids are currently attributed to Austropeplea Cotton, 1942 and Kutikina Ponder and Waterhouse 1997, which are thought to be represented by three and one species, respectively. Results of this study indicate there are 5 distinct species across three genera. Phylogenetic analyses of the A. tomentosa (Pfeiffer, 1855) complex recovered two distinct species, A. tomentosa in New Zealand and A. huonensis (Tenison-Woods, 1876) in southern Australia. There was however incongruence between the anatomical and molecular phylogenies. Kutikina hispida was suggested to be closely related to the A. tomentosa complex, however, molecular phylogenies genes resolved K. hispida as sister to A. huonensis, with A. tomentosa being resolved as sister to the A. huonensis + Kutikina clade. Kutikina was therefore synonymised into Austropeplea based on the molecular phylogenies. Based on molecular and anatomical phylogenies, the more northern complex, A. lessoni (Deshayes, 1830) was more appropriately placed in the Peplimnea (Iredale, 1943), and was found to be represented by two distinct taxa, P. lessoni and P. affinis (Küster, 1862). Phylogenetic analysis of 16S, ITS-2 and anatomical characters recovered A. viridis (Quoy and Gaimard, 1832) as relatively divergent from other members of Austropeplea. Therefore, A. viridis was placed into Viridigalba Kruglov and Starobogatov, 1985. iii Using 16S sequences and anatomical characters, a phylogeny of the Lymnaeidae was produced. The Australasian lymnaeids represented one of the most derived groups within the family in both the 16S and anatomical phylogenies. The North American and European lymnaeids were resolved at the base of the lymnaeid phylogeny, suggesting that these taxa represent the older groups within the family. Phylogenies based on molecular sequences suggest that the Austropeplea lessoni complex is more closely related to lymnaeids from South East Asia than to other Australian lymnaeids. Furthermore, based on molecular and anatomical phylogenies, A. viridis is suggested as sister to the A. tomentosa complex. Therefore it is highly likely the A. lessoni complex and A. tomentosa complex have separate derivations. The monophyly of Radix Montfort, 1810 remains however unresolved. Two theories of biogeography of the Australasian Lymnaeidae have been recently proposed and were examined in light of the new phylogeny. While it seems certain that the Austropeplea lessoni complex had a South East Asian origin, the origin of the A. tomentosa complex is still unclear. The close relationship of the A. tomentosa complex with Asian A. viridis plus the derived position of the group in the family, suggest a second invasion of Australia by lymnaeids from South East Asia. However, the basal position of the New Zealand A. tomentosa would suggest the group occurred here first and moved into Australia, thus suggesting a Gondwanan radiation of the A. tomentosa complex. The discovery of a lymnaeid fossil in Antarctica lends further weight to this theory. iv ACKNOWLEDGEMENTS There are a number of people I would like to acknowledge for their assistance and support throughout this project. Firstly my supervisors, Dr. Winston Ponder at the Australian Museum, Associate Professor Andy Davis and Dr Mark Dowton at the University of Wollongong, not only for their advice and comments relating to this project and earlier drafts of this thesis, but also their continual support and encouragement throughout my project. I would also like to thank my other committee member Dr. James Wallman. A special thankyou to Dr. Joe Boray, for his insights into these species and for his immense enthusiasm for this project. The Australian Museum was essential to this project. I would like to especially like to thank the staff of the Malacology, Ian Loch, Alison Miller, Janet Waterhouse and Holly Barlow, for all their assistance in helping me in numerous aspects of this project. Images of the radulae were produced using the Scanning Electron Microscope at the Australian Museum, with the help of Sue Lindsay. Statistical advise was provided by Prof. David Steel from the School of Mathematics and Applied Statistics, University of Wollongong. This project involved the collection of fresh material from numerous areas in Australia, New Zealand and South East Asia. For the Australian collections, I am very grateful to my volunteers, Melissa Thompson, Terry O’ Dwyer, Dave McKenna, Tanya Strevens, and Adrian Ferguson, who spent many hours looking for snails. I would also like to thank the Tasmanian National Parks for providing me with equipment to sample the Franklin River. I am very appreciative to Bob Hamilton- Bruce and Brian Smith for allowing me access to the South Australian Museum and Queen Victoria Museum, respectively. For the New Zealand collections I would like to thank the Dr. John Harding, Prof. Mike Winterbourn and Morgan Sproul from the Department of Biological Sciences, University of Christchurch, for equipment and field support. In the Philippines, Dr. Ayolani V. de Lara and Dr. Bobby Pagulayan provided invaluable logistics and support for collecting material. Thankyou to Christian Albrecht for supplying material from Indonesia. Additional funding in the form of small grants was provided by the Australian Museum, the New South Wales Linnaean Society, Australian Biological Resources Study, the Malacological Society of London, the Malacological Society of Australasia, and the Institute of Conservation Biology. v Table of Contents Chapter 1 Introduction...........................................................................................................1 1.1 Importance of the Lymnaeidae ..............................................................................................2 1.1.1 Parasite host interactions ..................................................................................................2 1.1.2 Conservation status...........................................................................................................5 1.2 Lymnaeidae biogeography and classification .......................................................................7 1.2.1 Classification of Lymnaeidae ...........................................................................................7 1.2.2 Lymnaeidae biogeography and evolution.........................................................................8 1.3 Previous systematic studies of the Lymnaeidae...................................................................13 1.3.1 Shell plasticity ................................................................................................................13 1.3.2 Anatomical variation ......................................................................................................15 1.3.3 Genetic studies................................................................................................................16 1.4 Australian lymnaeids...........................................................................................................18 1.4.1 Key gap in biogeography................................................................................................18 1.4.2 History of Austropeplea..................................................................................................18 1.4.3 Testing current taxonomy ...............................................................................................19 1.5 Methodology and Aims........................................................................................................21 1.5.1 Methodological approach ...............................................................................................21 1.5.2 Aims and objectives........................................................................................................21 1.5.3 Structure of Thesis..........................................................................................................22