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Home , Cimoliasaurus, Cryptoclidus, Dolichorhynchops, Mauisaurus, Pachypleurosaur, Plesiosauria

Records of the Westem Australian Museum Supplement No. 57: 201-205 (1999).

Recent developments in Australasian sauropterygian palaeontology (Reptilia: )

Arthur R.I. Cruickshankl, R. Ewan Fordyce2 and John A. Long3

1 Earth Sciences Section, Leicester City Museum, New Walk, Leicester LE1 7EA, UK, and Geology Department, Leicester University, Leicester LII 7RH, UK; email: [email protected] 2 Department of Geology, Otago University, PO Box 56, Dunedin, }Western Australian Museum, Francis Street, Perth, WA 6000,

Abstract -A brief review of recent research into Australasian sauropterygians is given. The earliest record is an from South Island, New Zealand. An Early record from Queensland, hitherto included in the is shown to be the last known pachypleurosaur. A diverse record of is known from the time of the break-up of East Gondwana, in marginal rift sediments of Western Australia and South Australia, dated to the earliest . The record of the marine incursion into the Eromanga Basin, Queensland, contains -age pliosaurs and elasmosaurs. The New Zealand plesiosaurian record contains mostly members of the 'long-necked' , all from the Haumurian stage of the -. One specimen represents a unique record of a cryptoclidid in Australasia, more closely related to the European than to the other late cryptoclidids known from South America and the Antarctic Peninsula.

INTRODUCTION NEW ZEALAND MATERIAL The sauropterygians were an entirely aquatic Sauropterygians have been known for over a group of which trace their ancestry to the century from the Haumurian Stage of the Late tangasaurids of Madagascar, and Campanian-Maastrichtian in South Island, New whose intermediate evolutionary stages, the Zealand (Welles and Gregg 1971; Hiller et al. 1997). Pachypleurosauridae and the Nothosauriformes, More recently, a rich fauna, including are best displayed in the Middle of the sauropterygians and other marine reptiles, has been European Alpine (Tethyan) region (Brown 1981; recovered from horizons of much the same age Carroll 1987). The best-known of the from the Mangahouanga Stream site in the North sauropterygians are the Plesiosauria, the earliest Island by Or Joan Wiffen and her associates (Wiffen of which is , also occurring in the and Moisley 1986; Molnar and Wiffen 1994; Wiffen European Tethyan realm, and of Anisian (Middle 1996; Long 1998). Fordyce (1991) comprehensively Triassic) age. A functional progression from reviewed the New Zealand laterally undulatory swimming, through a record, and Long (1998) included an illustrated 'rowing' phase, to underwater 'flight', akin to that summary of the known New Zealand practised by living sealions, is demonstrated in the marine reptiles. sauropterygians, with the plesiosaurians showing Another recent discovery in the New Zealand full adaptation to underwater flight. The Anisian, as part of the extension of the Tethys, Plesiosauria comprises the plesiomorphic comprises remnants of a pachypleurosaur Pliosauroidea (here we follow Brown 1981 in sauropterygian (Figure 2A). The evidence is in the recognizing only a single family, the : form of a single very well preserved posterior but other classifications recognize the additional dorsal or anterior sacral , and other bone families and Brachauchenidae); and fragments, showing strong affinities with European the more derived Plesiosauroidea, obtaining three forms, except that it is much larger than the families: the Plesiosauridae, the described . and the Cryptoclididae. The last two are well The plesiosauroids (Figure 2B,C) are represented represented in the Australasian realm (Figure I, by forms in both the Australian Albian and the New overleaf). Zealand Maastrichtian. The New Zealand 202 A.R.I. Cruickshank, R.E. Fordyce, l.A. Long

Casuarina Beach Mangahouanga Stream Tuarangisaurus, pliosaurid (LK) elasmosaur. pliosaur~ Darwin

Richmond region 0 Woolungasaurus (EK) Mount Morgan 0 Coober Pedy Kabarri sp. pachypleurosaur (EJ) Leptocleidus cryptoclidid? (EK) Brisbane clemai (EK) o Haumuri t'-- Bluff (LK) Geraldton elasmosaur? (MJ) Lightning R~dge ?(EK)J Waipara River (U<) Mauisaurus, pliosaurid Adelaide Sydney a)----- Shag Point MelbOU~ cryptoclidid? Dandaragan, Andamooka (LK) Gingin elasmosaur Otway Group , \ Strzelecki elasmosaur pliosaur (EK) plesiosaur (EK) Group (LK) M V plesiosaur 500 km (EK) 250- km Figure 1 Maps showing major occurrences of sauropterygian in Australia and New Zealand. EJ = ; MJ = ; EK = ; LK =.

elasmosaurs are historically important, having been large southern cryptoclidids in the Late Cretaceous reported from the earliest days of geological Palaeopacific, which, alongside the numerical exploration of that country (Long 1998). Two genera importance of the elasmosaurs, indicates an ocean of predominate in these faunas; , the more than minimal productivity at that time. historically important taxon, and Tuarangisaurus, Pliosauroids are also present in the Late collected by Joan Wiffen and colleagues (Wiffen and Cretaceous of New Zealand, based on generically Moisley 1986). The former is not well defined, being indeterminate postcranial material from Waipara based on a quantity of dissociated limb and other River and Haumuri Bluff districts described by postcranial material, whereas the latter is known Welles and Gregg (1971), and from the from a single and some uncertainly-associated Mangahouanga Stream site (Wiffen and Moisley vertebrae. Unfortunately there is no overlap of 1986). this material. However, re-examination of holdings in the Canterbury Museum and further collection of new specimens may solve this problem AUSTRALIAN MATERIAL (Hiller et al. 1997). A review of the Mount Morgan 'plesiosaur' Whereas elasmosaurids (Figure 2C) are the (Bartholomai 1966; Molnar 1991) has been apparently common plesiosaurian group found in undertaken by one of us (A.R.I.c.). This difficult New Zealand, a recently recognized cryptoclidid material consists of negative moulds in a from Shag Point, North Otago, presents a novel set ferruginous sandstone, and comprises remains of of adaptations (Cruickshank and Fordyce 1996, several individuals. The age is constrained as Early 1998). The specimen is from very near the top of the Jurassic (Playford and Cornelius 1967). A close Maastrichtian sequence, and at 6.5 m overall length examination of the material indicates that it has is among the largest of known cryptoclidids. The pachypleurosaur affinities, and is not plesiosaurian. skull is proportionally larger than normal for a The redescription will indicate that in the plesiosauroid and has relatively large orbits and Australasian Tethys there was an early temporal openings. Cladistic analysis shows it to be representative of the Sauropterygia and (if the closer to Cryptoclidus (Figure 2B) than to the other above identification is correct), the latest known two austral genera reported to date and pachypleurosaur. Turneria (Cabrera 1941; Chatterjee and Small 1989). It Although the plesiosaurs are taken to be a typical appears that there were at least two radiations of component of marine faunas, several Jurassic and Australasian sauropterygians 203

A ~I.._---

B

c

E

Figure 2 Representative skeletons of Mesozoic sauropterygian groups discussed in the text. The scale bar for A = 10 cm; for B-E = 1 m. A, a pachypleurosaur Pachyplelirosalirlls, Family Pachypleurosauridae. B, a short-necked plesiosaur Cryptoclidlis, Family Cryptoclididae. C, a long-necked plesiosaur HydrotherosalirllS, Family Elasmosauridae. D, a long-necked pliosaur , Family Pliosauridae. E, a short-necked pliosaur KrOnOSalirllS, Family Pliosauridae. A-C, E are after Carroll (1987), D is after Williston (1902). 204 A.R.I. Cmickshank, R.E. Fordyce, J.A. Long

Early Cretaceous specimens have been recovered vertebra, plus smaller elongate vertebrae belonging from 'non-marine' horizons (Cruickshank 1997). In to elasmosaurs are also known from the early Late the Early Cretaceous (/) of Cretaceous Molecap , at Dandaragan, Western Australia a new species, Leptocleidus clemai, Western Australia, and have recently been has recently been described from sediments described by Long and Cruickshank (1998). Other containing fossilized wood and a vertebra South Australian elasmosaurs include the (Long and Cruickshank 1996; Cruickshank and 'Andamooka ' (Rich and Rich 1985) and Long 1997). The Leptocleidus is known from a more unassigned opalized specimens, as well as close-inshore deposit in , and from a several occurrences reported and figured by Long non-marine 'Wealden' locality in England (1998) from isolated finds over many . (Andrews 1911, 1922). Another closely related specimen is the famous 'Eric', an almost complete opalized skeleton from the Maree Formation, a CONCLUSIONS near-shore marine deposit at Coober Pedy in South The Australasian realm seems to have been an Australia, which has been the subject of a thesis important area for the evolution of leptocleidid recently submitted by Schroeder (1998). Other pliosaurs in the shallow seas which resulted from fragmentary plesiosaurian material from the first rifting of the breakup of East Gondwana; it 'freshwater' deposits has been recorded from was also possibly the place where the early Andamooka in South Australia, as part of the radiation of polycotylids took place. It has at least sedimentary history of the marine incursion when one Triassic pachypleurosaur, and probably the and Australia broke apart. very last of them, in a freshwater refuge in what is Leptocleidids are relatively small plesiosaurs now Queensland. The Central Australian seaway which possibly fed on and cephalopods in the was host to one of the largest pliosaurs ever to surf-zone, or estuaries, and seem to be related to inhabit Mesozoic seas, as well as to its own large the 5 m long Early Jurassic genus . elasmosaur. They are also of interest in seeming to form an New Zealand has a wealth of Late Cretaceous intermediate stage towards the other, relatively plesiosauroids, indicating a rich marine fauna. small-sized, plesiosaur group, the polycotylids, a Finally, at the end of the Cretaceous, the entire common component of the Late Cretaceous Great spectrum of marine , with the exception of American Seaway (Figure 2D). 'Eric' is the youngest the Chelonia, became extinct. The first of the whales of known Leptocleidus species (Albian) and seems to did not appear until the early Eocene, after a gap of be the closest to the polycotylids of all the known 10 million years. The Cretaceous/Tertiary sequence species. A very early polycotylid is under study in is almost unbroken in many parts of New Zealand Brisbane by Drs Thulborn and Wade - the and it would be of great interest to analyse the 'Richmond pliosaur', known from a complete faunas of the Paleocene to see whether there were articulated skeleton almost 5 m in length (figured in any top tetrapod predators after the plesiosaurs and Long 1998: 146-147). , and before the advent of the whales. Historically important pliosaurid material has also been known from the Queensland Albian for many years, including Kronosaurus (Figure 2E), one REFERENCES of the largest sauropterygians ever described Andrews, C.W. (1911). Description of a new plesiosaur (Longman 1924). Kronosaurus queenslandicus is a (Plesiosaunls capensis sp. nov.) from the Uitenhage giant form reaching nearly 14 m, as shown by the Beds of Cape Colony. Annals of the South African reconstructed skeleton on display at the Harvard Museum 1: 309-322. University Museum of Comparative Zoology Andrews, C.W. (1922). Description of a new plesiosaur (Romer and Lewis 1959), although much of this from the of Berwick (Sussex). Quarterly reconstruction comprises plaster reconstructions of Journal ofthe Geological Society ofLondon 78: 285--295. missing pieces. Kronosaurus is now known from Bartholomai, A. (1966). The discovery of plesiosaurian remains in freshwater sediments in Queensland. almost a dozen specimens and is the subject of a Australian Journal ofScience 28: 437-438. doctoral dissertation by Colin McHenry of the Brown, D.5. (1981). The English Upper Jurassic University of Queensland. Plesiosauroidea (Reptilia) and a review of the Several elasmosaurs have been reported from phylogeny and classification of the Plesiosauroidea. Australia, but only one has been named. This is the Bulletin of the British Museum (Natural History) genus Woolungasaurus from the Albian of (Geology) 35: 253-347. Queensland (Persson 1982). The type is of Cabrera, A. (1941). Un plesiosauria nuevo del Cretacea additional interest as it shows clear evidence of how del Chabut. Revista Museo de la Plata (Paleontologia) 2: it met its demise: there are tooth marks on the side 113-130. of the skull and the skull has been crushed flat Carroll, R.L. (1987). Vertebrate paleontology and evolution: (Thulborn and Turner 1993). A very large dorsal i-xiv, 1'-{'98, Freeman, Chicago, n., U.5.A. Australasian sauropterygians 205

Chatterjee, S. and Small, B.). (1989). New plesiosaurs Vickers-Rich, P., Monaghan, ).M., Baird, R.F. and from the Upper Cretaceous of Antarctica. Geological Rich, T.H. (eds), Vertebrate palaeontology of Australasia: Society of London Special Publication 47: 197-215. 605-702, Pioneer Design Studio, Lilydale, Victoria. Cruickshank, A.R.I. (1997). A Lower Cretaceous Molnar, RE. and Wiffen, ). (1994). A Late Cretaceous pliosauroid from South Africa. Annals of the South polar dinosaur fauna from New Zealand. Cretaceous African Museum 105: 207-226. Research 15: 689-706. Cruickshank, AR.I. and Fordyce, R.E. (1996). A late Persson, P.O. (1982). Elasmosaurid skull from the Lower Cretaceous plesiosaur (Plesiosauria, Cryptoclididae?) Cretaceous of Queensland (Reptilia: Sauropterygia). from Shag Point, North Otago, New Zealand. Memoirs of the Queensland Museum 20: 647-655. Geological Society of New Zealand Miscellaneous Playford, G. and Cornelius, K.D. (1967). Palynological Publication 91a: 62. and lithostratigraphic features of the Razorback Beds, Cruickshank, A.R.I. and Fordyce, R.E. (1998). High Mount Morgan district, Queensland. University of latitude late Cretaceous plesiosaurs in Gondwana. Queensland Papers, Department ofGeology 6: 81-94. Journal ofAfrican Earth Sciences 27: 50-51. Rich, P.V. and Rich, T.H. (1985). Plesiosauridae. The Cruickshank, ARI. and Long, ).A (1997). A new species Andamooka sea monster. In Rich, P.V. and van Tets, of pliosaurid from the Early Cretaceous G.F. (eds), Kadimakara. Extinct vertebrates of Australia: Birdrong Sandstone of Western Australia. Records of 143-146, Pioneer Design Studio, Lilydale, Victoria. the Western Australian Museum 18: 263-276. Romer, AS. and Lewis, AD. (1959). Mounted skeleton of Fordyce, RE. (1991). A new look at the fossil vertebrate the giant plesiosaur Kronosaurus. Breviora 112: 1-15. record of New Zealand. In Vickers-Rich, P., Sehroeder, N. (1998). A review of order Pliosauria, and Monaghan, ).M., Baird, RF. and Rich, T.H. (eds), the description of a new, opalised pliosauroid, [name Vertebrate palaeontology of Australasia: 1191-1316. deleted], from the Early Cretaceous of Coober Pedy, Pioneer Design Studio, Lilydale, Victoria. South Australia. Unpublished M.Se. thesis, Monash Hiller, N., Mannering, A. and )ones, CM. (1997). University, Clayton, Victoria. Mauisaurus haasti - a new look at an old species of Thulborn, AR. and Turner, S. (1993). An elasmosaur plesiosaur. Abstracts, Conference on Australasian bitten by a pliosaur. Modern Geology 18: 489-511. Vertebrate Evolution, Palaeontology and Systematics, Welles, S.P. and Gregg, D.R (1971). Late Cretaceous Perth 7-11 July 1997: 31. marine reptiles of New Zealand. Records of the Long, ).A (1998). of Australia and New Zealand Canterbury Museum 9: I-Ill. and other of the Mes020ic Era: 1-188, University Wiffen, ). (1996). Dinosaurian palaeobiology: a New of New South Wales Press, Sydney, NSW. Zealand perspective. Memoirs of the Queensland Long, ).A and Cruickshank, ARI. (1996). First record of Museum 39: 725-731. an Early Cretaceous theropod dinosaur bone from Wiffen, ). and Moisley, W.L. (1986). Late Cretaceous Western Australia. Records of the Western Australian reptiles (families Elasmosauridae, Pliosauridae) from Museum 18: 219-221. the Mangahouanga Stream, North Island, New Long, ).A. and Cruickshank, A.R.I. (1998). Further Zealand. New Zealand Journal ofGeology and Geophysics records of plesiosaurian reptiles of )urassic and 29: 205-252. Cretaceous age from Western Australia. Records of the Williston, S.W. (1902). Restoration of Dolichorhynchops Western Australian Museum 19: 47-55. osborni, a new Cretaceous plesiosaur. Kansas Longman, H. (1924). A new gigantic from University Science Bulletin 1: 241-244. the Queensland Cretaceous, Kronosaurus queenslandicus, new genus and species. Memoirs of the Queensland Museum 8: 26-28. Manuscript received 11 February 1998; accepted 10 November Molnar, R.E. (1991). Fossil reptiles in Australia. In 1998.