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DISPERSED LEAF CUTICLE FROM THE EARLY MIOCENE OF SOUTHERN NEW ZEALAND
ABSTRACT
This paper describes 115 parataxa of dispersed leaf fossil cuticle from 120 samples from the Early Miocene of Central Otago (the fluvial-lacustrine Manuherikia Group) and Southland (the coastal deltaic East Southland Group), New Zealand. The modern affinities include Argophyllaceae (Argophyllum), Atherospermataceae, Casuarinaceae (Gymnostoma), Cunoniaceae-Elaeocarpaceae, Ericaceae, Gnetaceae, Grisseliniaceae (Grisellinia), Meliaceae, Menispermaceae, Monimiaceae (Hedycarya), Myrsinaceae, Proteaceae (incl. Lomatia and Placospermum), Santalaceae (Notothixos), Sapindaceae, Strasburgeriaceae (Strasburgeria), and Winteraceae. The records of Argophyllaceae, Menispermaceae, Placospermum and Notothixos are the first of these families and genera for New Zealand. For the Argophyllaceae and Notothixos at least, these are the first known fossil records. With the exception of Cunoniaceae-Elaeocarpaceae, Ericaceae, Grisseliniaceae, Myrsinaceae, and Winteraceae, which occur in the south of New Zealand today, the fossils indicate a more southerly range extension in the Early Miocene than today. This evidence of extended range along with a previously published high diversity of Lauraceae and conifers is probably the result of warmer conditions despite the fossil localities lying at about 50šS in the Early Miocene – about 5 degrees further south than today. Argophyllum and Strasburgeria are evidence of a biogeographical link with New Caledonia, where they are now restricted. The plants were components of rainforest vegetation growing in microthermal to mesothermal temperatures.
Mike Pole. Queensland Herbarium, Brisbane Botanic Gardens Mt Coot-tha, Mt Coot-tha Rd, Toowong QLD 4066, Australia
KEY WORDS: Early Miocene, cuticle, stomata, epidermis, biogeography, biodiversity
PE Article Number: 11.2.15A
Copyright: Palaeontological Association October 2008
Submission: 12 January 2008. Acceptance: 10 September 2008
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