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Dragons in the mist: origin and diversification of the austral genus Dracophyllum (Ericaceae ). Steven J. Wagstaff 1 , Murray I. Dawson 1 , S. Venter 2 , Jérôme Munzinger 3 , Darren M. Crayn 4 , Dorothy A. Steane 5 , Kristina L. Lemson 6. Dracophyllum subgenus Dracophyllum.
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Dragons in the mist: origin and diversification of the austral genus Dracophyllum (Ericaceae) Steven J. Wagstaff1, Murray I. Dawson1, S. Venter2, Jérôme Munzinger3, Darren M. Crayn4, Dorothy A. Steane5, Kristina L. Lemson6
Dracophyllum subgenus Dracophyllum About 21 species are placed in subgenus Dracophyllum; 7 of these are found only in New Zealand, 8 are confined to New Caledonia, 4 to Australia, 1 to Tasmania, and 1 to Lord Howe Island. D. fitzgeraldii D. oceanicum D. mackeeanum D. ouaiemense D. verticillatum D. fiordense
Dracophyllum subgenus Oreothamnus Some 29 species are recognized in subgenus Oreothamnus. With the exception of D. minimum found in Tasmania, they are endemic to New Zealand. D. longifolium D. pronum D. muscoides D. minimum
Dracophyllum subgenus Cordophyllum Subgenus Cordophyllum includes a single species, Dracophyllum involucratum, which is restricted to New Caledonia D. involucratum
Richea 11 species are recognized that are placed in two sections. These are restricted to Tasmania and southeastern Australia R. continentis R. sprengelioides R. scoparia R. victoriana R. pandanifolia
Sphenotoma Includes about 8 species that are restricted to Southwestern Australia S. gracile S. dracophylloides S. capitata
Distribution of Dracophyllum and its relatives Sphenotoma and Richea
Predictions • Differences in taxonomic interpretation • Fragmentation and extinction • Long-distance dispersal with prevailing westerly winds • Recent founder speciation on oceanic islands rather than greater age
New Caledonia Australia New Zealand Australia
Jordan, G.J.; Bannister, J.M.; Mildenhall, D.C.; Zetter, R.; Lee, D.E. 2010. Fossil Ericaceae from New Zealand: Deconstructing the use of fossil evidence in historical biogeography. American Journal of Botany 97: 59-70. Furness, Caroll A. 2009. Pollen evolution and development in Ericaceae, with particular reference to pseudomonads and variable pollen Sterility in Styphelioideae. International Journal of Plant Sciences 170: 476-495.
23.8 Ma Fixed age 90 Ma
“During the late Miocene-Pliocene at least 15 families and a minimum of 36 genera were lost from the New Zealand flora” Lee, D.E.; Lee, W.G.; Mortimer, N. 2001. Where and why have all the flowers gone? Depletion and turnover in the New Zealand Cenozoic angiosperm flora in relation to palaeogeography and climate. Australian Journal of Botany 49: 341-356. http://www.gns.cri.nz/Home/Learning/Science-Topics/Fossils/NZ-fossils/Fossil-Plants
Nathan, R.; Schurr, F.M.; Spiegel, O.; Steinitz, O.; Trakhtenbrot, A.; Tsoar, A. 2008. Mechanisms of long-distance seed dispersal. Trends in Ecology & Evolution 23: 638-647.
Satellite image of cyclone Larry as it was bearing down on the coast of Queensland. The storm sustained wind speeds of 185 km/hr before it came ashore. NASA image by Jeff Schmaltz
Barraclough, T.G.; Nee, S. 2001. Phylogenetics and speciation. Trends in Ecology & Evolution 16: 391-399.
Summary • Sphenotoma monophyletic; Dracophyllum paraphyletic, and Richea polyphyletic. • Species richness greatest in New Zealand and New Caledonia, but phylogenetic diversity greatest in Australia • Oligocene-early Miocene fossils in New Zealand may represent extinct lineages distantly related to extant species of Dracophyllum • Australian species of Dracophyllum remnants of older widely distributed lineages • In contrast the extant species in New Zealand and New Caledonia species radiated more recently following long-distance dispersal
Steven J. Wagstaff1, Murray I. Dawson1,Stephanus Venter2, Jérôme Munzinger3, Darren M. Crayn4, Dorothy A. Steane5, Kristina L. Lemson6 1Allan Herbarium, Landcare Research, PO Box 40, Lincoln 7640, New Zealand. 2Botanical and Environmental Consultant, PO Box 63, Trinity Beach, Queensland, 4879, Queensland, Australia. 3IRD, UMR AMAP, d’Ecologie Végétale Appliquées, Herbarium NOU, F-98848 New Caledonia. 4Australian Tropical Herbarium, James Cook University Cairns Campus, PO Box 6811, Cairns 4870, Australia. 5School of Plant Science, University of Tasmania, Private Bag 55, Hobart, Tasmania 7001, Australia. 6Centre for Ecosystem Management & School of Natural Sciences, Edith Cowan University, 100 Joondalup Drive, Joondalup, Western Australia 6027, Australia. Wagstaff, S.J.; Dawson, M.I.; Venter, S.; Munzinger, J.; Crayn, D.M.; Steane, D.A.; Lemson, K.L. 2010. Origin, diversification, and classification of the Australasian Genus Dracophyllum (Richeeae, Ericaceae). Annals of the Missouri Botanical Garden 97: 235-258. http://www.bioone.org/doi/abs/10.3417/2008130
Acknowledgments This research was supported in part by a National Geographic Society’s Committee for Research and Exploration grant 7774–05 and the New Zealand Foundation for Research, Science and Technology through the Defining New Zealand’s Land Biota OBI. The authors thank many individuals for their assistance with fieldwork, including those from Australia: Jayne Balmer and Jaz Jaynes (Tasmania); Spiro Buhagiar, Ray Moore, and Michelle Nissen (Queensland); Andrew Perkins, Muhammad Iqbal and Brendon Neilly (New South Wales); Ian Hutton and Terry Wilson (Lord Howe Island); and Michel Blanc, Daniel and Irène Létocart (New Caledonia). Mary Korver, Peter de Lange and Phil Garnock-Jones of New Zealand collected specimens of Dracophyllum from Tasmania, the Chatham, Three Kings and subantarctic islands. Earlier drafts benefited greatly from the insightful comments of Greg Jordan, Daphne Lee, Ilse Breitwieser, Thomas Buckley, Walt Judd, Kathy Kron and Ulf Swensen.