Fish remains, mostly otoliths, from the non-marine early Miocene of Otago, New Zealand

Fish remains described from the early Miocene lacustrine Bannockburn Formation of Central Otago, New Zealand, consist of several thousand otoliths and one skeleton plus another disintegrated skull. One species, Mataichthys bictenatus Schwarzhans, Scofield, Tennyson, and T. Worthy gen. et sp. nov., an eleotrid, is established on a skeleton with otoliths in situ. The soft embedding rock and delicate, three−dimensionally preserved fish bones were studied by CT−scanning technology rather than physical preparation, except where needed to extract the otolith. Fourteen species of fishes are described, 12 new to science and two in open nomenclature, representing the families Galaxiidae (Galaxias angustiventris, G. bobmcdowalli, G. brevicauda, G. papilionis, G. parvirostris, G. tabidus), Retropinnidae (Prototroctes modestus, P. vertex), and Eleotridae (Mataichthys bictenatus, M. procerus, M. rhinoceros, M. taurinus). These findings prove that most of the current endemic New Zealand/southern Australia freshwater fish fauna was firmly established in New Zealand as early as 19–16 Ma ago. Most fish species indicate the presence of large fishes, in some cases larger than Recent species of related taxa, for instance in the eleotrid genus Mataichthys when compared to the extant Gobiomorphus. The finding of a few otoliths from marine fishes corroborates the age determination of the Bannockburn Formation as the Altonian stage of the New Zealand marine Tertiary stratigraphy.Werner Schwarzhans, R. Paul Scofield, Alan J.D. Tennyson, Jennifer P. Worthy, and Trevor H. Worth

The early Miocene paleolake Manuherikia: vegetation heterogeneity and warm-temperate to subtropical climate in southern New Zealand

The Manuherikia Group in southern New Zealand represents terrestrial sediments associated with a large paleolake, Lake Manuherikia, formed during a period of basin subsidence in the early Miocene, ca. 18.7–15.1 Ma. Micro- and macrofloral assemblages collected throughout the Manuherikia Group were studied to derive terrestrial climate proxies, relying on leaf physiognomy (CLAMP) and taxonomic affinity (bioclimatic analysis). The assemblages were also analyzed for the component loading of the relative abundances of different leaf morphotypes and the results were interpreted in light of stratigraphic and lateral ecological variation. Independent paleoclimate proxies from a variety of depositional environments consistently indicate warm-temperate to marginally subtropical mean annual temperatures (16.5–20 C) and high annual precipitation (1,500–2,500 mm) during the Burdigalian– Langhian of mid-latitude New Zealand. Leaf physiognomy reveals an amplified seasonal contrast in both precipitation and temperature, possibly caused by seasonal shifts in the position of the subtropical highpressure cells and westerly wind belts, causing overcast wet winters and dry summers. Regional and local vegetation variation was most likely caused by fluctuations in lake levels, which in turn may have been affected by enhanced seasonality from shortterm climate oscillations. Keywords Paleoenvironment Mid-latitudes Floral proxies Southern hemisphere SubtropicalTammo Reichgelt, Elizabeth M. Kennedy, John G. Conran, Dallas C. Mildenhall, Daphne E. Le

A new Miocene fern (Palaeosorum: Polypodiaceae) from New Zealand bearing in situ spores of Polypodiisporites

A new species of fossil fern with in situ spores, Palaeosorum waipiata (Polypodiaceae), is described and figured for a microsoroid fern frond from earliest Miocene sediments in Otago, New Zealand. The fertile frond from the Foulden Maar fossil Lagerstätte is pinnatifid with deep narrow lobes with entire margins and bears circular sori without indusia in rows on either side of the lobe midrib. Monolete spores associated with the frond are differentiated from similar, widespread dispersed spores of Polypodiisporites radiatus in possessing very small proximal verrucae/granulae around the laesurae and more rounded verrucae and the description of Palaeosorum is expanded to include information about sori and spores. This is the first confident Southern Hemisphere record for a microsoroid fern macrofossil, as well as the first with in situ spores. It is probable that this fern was epiphytic on trees or lithophytic on rocks adjacent to the Miocene maar lake.Uwe Kaulfuss, John G. Conran, Jennifer M. Bannister, Dallas C. Mildenhall and Daphne E. Le

The monocot fossil pollen record of New Zealand and its implications for palaeoclimates and environments

Published online: 19 May 2015Abstract not availableJohn G. Conran, Dallas C. Mildenhall, J. Ian Raine, Elizabeth M. Kennedy and Daphne E. Le

An Akania (Akaniaceae) inflorescence with associated pollen from the early Miocene of New Zealand

PREMISE OF THE STUDY:An Akania-like inflorescence, including flowers with in situ pollen was recovered from the remarkable Konservat-Lagerstätte lacustrine diatomite deposit at Foulden Maar, Otago indicating the presence of Akaniaceae in southern New Zealand during the early Miocene. The flowers, although slightly smaller than the sole modern Australian species, A. bidwillii, contain pollen grains that are very like that taxon. The pollen also resembles that of the monospecific sister genus Bretschneidera from Southeast Asia and India, although that taxon has flowers with very different morphology from this genus. METHODS:The floral morphology of the fossil and in situ pollen grains were compared with flowers and pollen grains from extant species of Akaniaceae and related taxa. KEY RESULTS:The fossil inflorescence and associated pollen are referred to a new, extinct species of Akania: Akania gibsonorum. The floral structures and pollen resemble those of the modern Australian Akania species. CONCLUSIONS:The discovery of fossil flowers of Akania in an early Miocene lake deposit in New Zealand, coupled with earlier recognition of Akaniaceae leaves from the Paleocene epoch and wood from the Miocene epoch in South America suggests that the genus was once widespread in former Gondwana landmasses. The extinction of Akaniaceae in New Zealand and South America, and its present relictual distribution in eastern Australia, is most likely related to post-Miocene climatic cooling.John G. Conran, Uwe Kaulfuss, Jennifer M. Bannister, Dallas C. Mildenhall and Daphne E. Le

Leaf fossils of Luzuriaga and a monocot flower with in situ pollen of Liliacidites contortus Mildenh. & bannister sp. nov. (alstroemeriaceae) from the Early Miocene

PREMISE OF THE STUDY: The Foulden Maar lake sediments in Otago, South Island, New Zealand, date to the earliest Miocene and provide an important picture of the diversity of the Australasian biota, paleoecology, and climate at a time when New Zealand had a smaller land area than today. The diverse rainforest contains many taxa now restricted to Australia, New Caledonia, or South America. The presence of Luzuriaga-like fossils in these deposits is important for understanding Alstroemeriaceae evolution and the biogeography of genera shared between New Zealand and South America. METHODS: Leaves and a flower with in situ pollen that resemble extant Luzuriaga are described and placed phylogenetically. Geographic range information and a molecular clock model for the Alstroemeriaceae were used to investigate possible biogeographic scenarios and the influence of the new fossil on inferred divergence times. KEY RESULTS: Luzuriaga peterbannisteri Conran, Bannister, Mildenh., & D.E.Lee sp. nov. represents the first macrofossil record for Alstroemeriaceae. An associated Luzuriaga-like flower with in situ fossil pollen of Liliacidites contortus Mildenh. & Bannister sp. nov. is also described. The biogeographic analysis suggests that there have been several dispersal events across the Southern Ocean for the genus, with the fossil representing a now-extinct New Zealand lineage. CONCLUSIONS: Luzuriaga was present in Early Miocene New Zealand, indicating a long paleogeographic history for the genus, and L. peterbannisteri strengthens biogeographic connections between South America and Australasia during the Oligocene and earliest Miocene.John G. Conran, Jennifer M. Bannister, Dallas C. Mildenhall, Daphne E. Lee, Juliana Chacón, and Susanne S. Renne

Palynology of the early Miocene Foulden Maar, Otago, New Zealand: diversity following destruction

Abstract not availableDallas C. Mildenhall, Elizabeth M. Kennedy, Daphne E. Lee, Uwe Kaulfuss, Jennifer M. Bannister, Bethany Fox, John G. Conra

Subtropical rainforest vegetation from Cosy Dell, Southland: plant fossil evidence for Late Oligocene terrestrial ecosystems

Published online: 31 Mar 2014A fossil flora from the basal Chatton Formation at Cosy Dell farm near Waimumu, Southland, New Zealand comprises wood, seeds, pollen and spores. A Late Oligocene age (25.4–24.4 Ma) determined from macro- and nannofossils constrains the beginning of marine transgression in this area. The palynoflora comprises more than 100 taxa, in addition to a few spores recycled from underlying Jurassic Murihiku basement. At least 16 ferns are present. Conifers include Araucariaceae and Podocarpaceae (Dacrydium, Dacrycarpus, Lagarostrobos, Microcachrys, Phyllocladus and Podocarpus). The angiosperm palynoflora comprises monocots including Arecaceae, Asparagaceae, Asteliaceae, Pandanaceae and Typhaceae and numerous dicots including Casuarinaceae, Cunoniaceae, Euphorbiaceae, Loranthaceae, Malvaceae, Myrtaceae, Nothofagaceae, Proteaceae and Strasburgeriaceae. The drift flora includes wood and seeds including the tropical legume Entada. Elongate limpets and mangrove snails provide indirect evidence for seagrasses and mangroves. The predominance of rainforest tree pollen and fern spores suggests a regional subtropical coastal forest and high rainfall.JG Conran, DC Mildenhall, DE Lee, JK Lindqvist, C Shepherd, AG Beu, JM Bannister and JK Stei