Astelia

Abstract: The modern New Zealand flora has a relatively low number of families and genera in relation to land area, but well-preserved macrofossils and pollen from three sites in southern New Zealand suggest that the floras in Eocene, Oligocene and Miocene times were much more diverse at the generic level. At Pikopiko, Southland, a late Eocene in situ forest with fern understory was dominated by conifers, Casuarinaceae, Lauraceae, Nothofagus, Proteaceae, and mesothermal angiosperms including palms (aff. Calamus), Sapindaceae: Cupaniae and Picrodendraceae. At Newvale Mine, Southland, a leaf bed within a thick lignite seam represents leaf fossils preserved in a late Oligocene oligotrophic bog. This site demonstrates that Agathis, Dacrycarpus, Dacrydium, Halocarpus, Microcachrys, Podocarpus and Phyllocladus coexisted with diverse angiosperms including Nothofagus, Gymnostoma, Cunoniaceae, Ericaceae, Sapindaceae and several Proteaceae. Pollen data add Meliaceae, Myrtaceae, Onagraceae and Rubiaceae to the flora. At Foulden Maar, Otago, mummified leaves and flowers, including several with in situ pollen, demonstrate the existence of a diverse flora surrounding an Early Miocene lake. This site contains numerous monocot macrofossils including Astelia, Cordyline, Ripogonum and Typha, as well as the oldest fossils known for Orchidaceae and Luzuriagaceae. This flora was dominated by Lauraceae with affinities to Cryptocarya and Litsea, but other families include Araliaceae, Cunoniaceae, Elaeocarpaceae, Euphorbiaceae sensu lato, Menispermaceae, Myrsinaceae, Myrtaceae, Onagraceae, Proteaceae and Sterculiaceae. Many ferns, conifers, and Nothofagus are from lineages with Gondwanan ancestors, whereas other taxa show links to Australia (e.g., Gyrostemonaceae), New Caledonia (e.g., Beauprea) and South America (e.g., Luzuriaga, Fuchsia). Many of these taxa are now extinct in New Zealand, and therefore indicate much wider biogeographic ranges for many families and genera in the past.

Abstract: The relatively simple flora and structure of Nothofagus cunnirzghantii cool temperate rainforest in Tasmania is widely accepted to be the result of repeated glaciation during the Pleistocene. Plant macrofossils, spores and pollen preserved at Regatta Point, western Tasmania, indicate that several gymnosperms and subcanopy angiosperms with warm temperate affinities had survived one to several episodes of cold, possibly glacial climates, before becoming extinct in the early to middle Pleistocene: Callitris/Actirzostrobus, Dacrycarpus, Austromyrtus, Eucalyptus spathulata-type, Haloragodendron-type, Loranthaceae, Quintinia and Symplocos. These co-existed in Nothofagus-Lagarostrobos franklinii rainforest with a number of taxa that are now restricted to upper subalpine-alpine habitats in Tasmania, such as Astelia, Gunnera and Microcachrys. The community is difficult to interpret in terms of modem species and we propose that either extinct taxa are being concealed by essentially modem pollen morphologies, that ecological preferences have altered since the early-middle Pleistocene, or both. Patterns of extinctions in Tasmania (and New Zealand) suggest that Pleistocene climatic change at middle-high latitudes presented an environmental stress not previously experienced during the Cenozoic, perhaps through widespread periglacial conditions, but also provided ecological and evolutionary opportunities for rainforest species tolerant of a wide range of conditions experienced during the late Pleistocene.

Abstract: Monocot cuticle is an uncommon component of dispersed cuticle samples in the New Zealand Miocene, a fact most likely due to its generally fragile nature. Nevertheless, 120 fossiliferous samples from two regions, the interior Manuherikia Basin in Central Otago, and the paleo-coastal delta of the Southland Coalfield, have produced 17 morphological types of cuticle, 15 of which are clearly monocot. These are described as parataxa and are regarded as including Astelia, Arecaceae, Rhipogonum, Pandanaceae, and Typhaceae. Most of the fossils remain unidentified, but are probably semiaquatic swamp plants. Six forms of fossil Typha seeds are also illustrated.