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Angiosperms are by far the most important plant group for human beings, and numerous fossils of early angiosperms have been documented worldwide 1-14. However, the origin of angiosperms remains a focus of debate 15-19, partially due to lack of anatomically preserved fossils of related plant reproductive organs. Here we report a fossil female flower, Xilinia shengliensis gen. et sp. nov, that demonstrates angio-ovuly — the feature characteristic of angiosperms as well as cone-like morphology that is unusual in angiosperms. Its chimeric character assemblage makes Xilinia unique and informative for flower origin and evolution.

Nanjinganthus is an Early Jurassic angiosperm recognized based on the study of over 200 specimens. However, some other authors have misinterpreted these fossils. Here the authors try to remedy the problems, by pointing out the logical pitfalls in these publications and underscoring a long-used, workable criterion for early angiosperms. The paper explains the cons and pros of this criterion, hoping to bring palaeobotany and plant taxonomy back to a consistent and practical track. Nanjinganthus is an angiosperm.

Large areas of Earth’s continents were covered by temperate forests before the dramatic increase of the human population in the past two millennia. Prior to human expansion, temperate forests were more extensive in the Neogene (23–2.6 Ma) when climate at the middle latitudes was slightly warmer and more equable than at the present. These temperate forests exhibited a high diversity of plant taxa, higher than today in several geographical areas. Such high diversity in the past can be explained by two reasons. First, angiosperms originated in the Cretaceous and underwent an important phylogenetic diversification during and shortly after that period. These new plant lineages easily dispersed between North America and Eurasia, and biogeographic range expansions continued across other continents. Second, since the Eocene/Oligocene transition (c. 34 Ma), several members of tropical/subtropical lineages adapted to cooler conditions and entered the warmer temperate realm. An equable climate with abundant precipitation in widespread areas provided a suitable habitat for moisture-requiring woody plants. The higher floristic diversity in the Neogene compared to the present is best illustrated by European fossil plants and, to a lesser extent, by those in North America. The area covered by temperate forests in South America decreased consistently after the late Miocene, and the dominant woody plants of the Neogene remained only in the westernmost regions. A floristic impoverishment is not clearly documented in Australia, where there was a much higher diversity of conifers in the Oligocene-Miocene than today. Beginning some 6 million years ago, several global intervals of colder and/or drier climate reduced the habitat of those taxa that required nonfreezing temperatures and moisture, finally resulting in a large mass extirpation/extinction of thermophilous plants in western Eurasia. This turnover occurred primarily between 3.5 and 1.0 million years ago. The trend was different in eastern Eurasia where extirpation/extinction has been rather limited. In conclusion, the mid-latitudes of all the continents witnessed a triumph of the extension and diversity of temperate forests from about 34 to 3 million years ago (Oligocene-Pliocene) and, in many temperate places, these grew under wetter and warmer conditions than today.

The Upper Triassic Xujiahe and Lower Jurassic Zhenzhuchong formations of the Sichuan Basin, China, are important sources of plant fossils and windows into the intervening extinction event. However, there is an on-going debate as to whether the environment represented by the Xujiahe and Zhenzhuchong formations was continental or included an important marine component. We studied the Xujiahe–Zhenzhuchong section near Qili Town of Xuanhan County, in the east of the basin and report hummocky and swaley cross-stratification in the Xujiahe Formation. This, along with minor Skolithos and heterolithic bedding, provides strong evidence for shallow marine conditions and favours an interpretation as the deposits of a wave-dominated coast. It also suggests common and extreme storm activity, possibly hurricanes, at what was a mid-latitude (c. 34–40°N) location in the Late Triassic. Charcoal is found in most samples throughout the section. The predominant fossil wood morphology is consistent with Xenoxylon. Together, the sedimentological evidence of storms and fire suggests a highly disturbed environment.

Two types of fossil Terminalia (Combretaceae) fruits are described from warmer periods in New Zealand's past. One is represented by large “fin-winged” fruit (samara) from the Early Miocene Manuherikia Group sediments of Bannockburn and the Nevis Valley. The form and size of the fruits are entirely unknown in New Zealand today, but strongly resemble those of the genus Terminalia with which they are identified. The second are numerous fruits from the Late Pliocene drift deposit of Weymouth, Manukau Harbour. These are identified with the common drift-fruit, Terminalia catappa, the “sea almond”. The presence of Terminalia in the Miocene and Pliocene of New Zealand is consistent with warmer conditions at those times. The later extinction of the genus meant the loss of the Combretaceae from New Zealand, which is not in the current flora. Based on the current climatic range of other Terminalia around the world, and most Combretaceae, the extinction and continuing absence are probably linked to cold climate conditions.

Equisetum is described for the first time from Cenozoic deposits of New Zealand. The fossils derive from two early to earliest middle Miocene assemblages in South Island, New Zealand. The fossils are ascribed tentatively to subgenus Equisetum based on their possession of whorled branch scars, but they cannot be assigned with confidence to a formal species. The decline of equisetaleans, otherwise unknown from the Cenozoic of the New Zealand-Australian-Antarctic domain, was possibly a consequence of severe environmental changes – particularly, abrupt shifts in the temperature and soil moisture regime – experienced by this region in the Neogene, coupled with competition from opportunistic angiosperms. Additional funding from US National Science Foundation (project #1636625)

In the Late Triassic–Early Jurassic, forests dominated by Podozamites—an apparently deciduous, shoot-dropping conifer with broad, multi-veined leaves—were extensive in what were the mid-latitudes of eastern Asia. Podozamites was the only conifer in many forests of this region, and at times appeared to have formed an almost mono-specific vegetation. Podozamites appears to have been little-effected through the Triassic–Jurassic transition, but responded to climate changes later in the Jurassic. The Chinese region progressively dried through the Middle Jurassic and aridity had developed in some areas by the Late Jurassic–Early Cretaceous. The centre of distribution of Podozamites shifted north, to the Siberian region, where conditions remained wet. There, it typically coexisted with conifers having a diverse range of smaller leaf morphologies. By the late Albian angiosperms had arrived in the Siberian area and risen to dominance. Some time after this event, Podozamites became extinct. This is significant, as it represents the permanent extinction of a unique lifestyle—a deciduous, broad-leaved and multi-veined conifer. The broad history of Podozamites raises some interesting issues: 1. The existence of a large, dominantly deciduous vegetation at mid-latitudes in the Late Triassic–Early Jurassic is little discussed. 2. It is unexpected that as broad-leaved angiosperms took over, amongst the conifers it was the broad leaved, multi-veined Podozamites that became extinct. This is the morphology that might have been expected to compete with the apparently more shade-forming angiosperms. Instead, it was the smaller leaved and single-veined conifers that remained to coexist with the angiosperms.

Reliable reconstructions of atmospheric carbon dioxide concentrations (pCO2) are required at higher resolution than currently available to help resolve the relationship between mass extinctions and changes in palaeo-pCO2 levels. Such reconstructions are needed: 1, at a high temporal resolution for constraining the pre- and post-extinction atmospheres; and 2, at a sufficient spatial resolution to constrain potential inter-hemispheric differences. Here we estimate pCO2 based on fossil Lauraceae leaf cuticle specimens derived from three localities with strata spanning the latest Cretaceous to the mid-Paleocene, including a new Cretaceous–Paleogene boundary (K–Pg) locality, in New Zealand. We use two independent methods of stomatal density-based pCO2 reconstructions; a transfer function calibrated using herbarium material and the stomatal ratio method, producing three calibration sets. Our results based on the mean values of each of the three calibration methods indicate pCO2 ranging between ca. 460 and 650ppm during the latest Cretaceous, falling precipitously to average values between ca. 360 and 430ppm across the K–Pg boundary, and further to ca. 305–320ppm in the mid-Paleocene. A ‘spike’ of extremely high pCO2 at the K–Pg could not be confirmed, but our results are, nonetheless, consistent with previously published pCO2 records from the Northern Hemisphere, and show that stomatal density worldwide was responding to significant changes in pCO2 across the K–Pg.

Reducing the uncertainty in predictions of future climate change is one of today’s greatest scientific challenges, with many significant problems unsolved, including the relationship between pCO2 and global temperature. To better constrain these forecasts, it is meaningful to study past time intervals of global warmth, such as the Eocene (56.0–33.9 Ma), serving as climatic analogues for the future. Here we reconstructed pCO2 using the stomatal densities of a large fossil Lauraceae (laurel) leaf database from ten sites across the Eocene of Australia and New Zealand. We show that mostly moderate pCO2 levels of ∼450–600 ppm prevailed throughout the Eocene, levels that are considerably lower than the pCO2 forcing currently needed to recreate Eocene temperatures in climate models. Our data record significantly lower pCO2 than inferred from marine isotopes, but concur with previously published Northern Hemisphere Eocene stomatal proxy pCO2. We argue that the now globally consistent stomatal proxy pCO2 record for the Eocene is robust and that climate sensitivity was elevated and/or that additional climate forcings operated more powerfully than previously assumed. Additional funding from the Bolin Centre for Climate Research, Stockholm University

The origin of angiosperms has been a long-standing botanical debate. The great diversity of angiosperms in the Early Cretaceous makes the Jurassic a promising period in which to anticipate the origins of the angiosperms. Here, based on observations of 264 specimens of 198 individual flowers preserved on 34 slabs in various states and orientations, from the South Xiangshan Formation (Early Jurassic) of China, we describe a fossil flower, Nanjinganthus dendrostyla gen. et sp. nov.. The large number of specimens and various preservations allow for an evidence-based reconstruction of the flower. From the evidence of the combination of an invaginated receptacle and ovarian roof, we infer that the seeds of Nanjinganthus were completely enclosed. Evidence of an actinomorphic flower with a dendroid style, cup-form receptacle, and angiospermy, is consistent with Nanjinganthus being a bona fide angiosperm from the Jurassic, an inference that we hope will re-invigorate research into angiosperm origins., eLife digest From oranges to apples, flowering plants produce most of the fruits and vegetables that we can see on display in a supermarket. While we may take little notice of the poppy fields and plum blossoms around us, how flowers came to be has been an intensely debated mystery. The current understanding, which is mainly based on previously available fossils, is that flowers appeared about 125 million years ago in the Cretaceous, an era during which many insects such as bees also emerged. But not everybody agrees that this is the case. Genetic analyses, for example, suggest that flowering plants are much more ancient. Another intriguing element is that flowers seemed to have arisen during the Cretaceous ‘out of nowhere’. Fossils are essential to help settle the debate but it takes diligence and luck to find something as fragile as a flower preserved in rocks for millions of years. In addition, digging out what could look like a bloom is not enough. It is only if the ovules (the cells that will become seeds when fertilized) of the plant are completely enclosed inside the ovary before pollination that researchers can definitely say that they have found a ‘true’ flower. Now, Fu et al. describe over 200 specimens of a new fossil flower that presents this characteristic, as well as other distinctive features such as petals and sepals – the leaf-like parts that protect a flower bud. Called Nanjinganthus, the plant dates back to more than 174 million years ago, making it the oldest known record of a ‘true’ flower by almost 50 million years. Contrary to mainstream belief, this would place the apparition of flowering plants to the Early Jurassic, the period that saw dinosaurs dominating the planet. This discovery may reshape our current understanding of the evolution of flowers.

Two relatively small tridactyl tracks from the Middle Jurassic Xintiangou Formation of northeastern Sichuan are assigned to cf. Anomoepus based on low length/width and anterior triangle ratios, and a relatively short step and inward rotation of the footprint axes. Anomoepus is typical of many Middle Jurassic dinosaur-dominated ichnofaunas from central and southern China and appears to be allied to the globally widespread Lower Jurassic tetrapod track biochron.

The origin of angiosperms has been the focus of intensive botanical debate for well over a century. The great diversity of angiosperms in the Early Cretaceous makes the Jurassic rather expected to elucidate the origin of angiosperm. Former reports of early angiosperms are frequently based on a single specimen, making many conclusions tentative. Here, based on observations of 284 individual flowers preserved on 28 slabs in various states and orientations, we describe a fossil flower, Nanjinganthus dendrostyla gen. et sp. nov., from the South Xiangshan Formation (Early Jurassic) of China. The large number of specimens and various preservations allows us to give an evidenced interpretation of the flower. The complete enclosure of ovules in Nanjinganthus is fulfilled by a combination of an invaginated and ovarian roof. Characterized by its actinomorphic flower with a dendroid style, cup-form receptacle, and angio-ovuly, Nanjinganthus is a bona fide angiosperm from the Jurassic. Nanjinganthus re-confirms the existence of Jurassic angiosperms and provides first-hand raw data for new analyses on the origin and history of angiosperms.

Three features of leaf physiognomy: craspedodromous venation, compound teeth and a lobed leaf outline, figure prominently in the Late Cretaceous vegetation of southern New Zealand. These make it distinctly different from typical extant, predominantly evergreen forests and some deciduous vegetation. The physiognomy of the Late Cretaceous vegetation at the assemblage level shows more similarity with predominantly deciduous forests of the Northern Hemisphere, in terms of the proportions of these characters in the flora. At the taxon level, combinations of characters found in fossils are very similar to and in some cases restricted to, widespread extant Northern Hemisphere deciduous taxa, but also to rarer components of evergreen forests. It may not be possible to categorically determine whether any one fossil was deciduous. The distinctly different assemblage-level foliar physiognomy implies a distinctly different “lifestyle” for the New Zealand forests that bordered Gondwana in the Late Cretaceous. It is highly likely that this physiognomy reflects an important deciduous component. This is unexpected as for at least part of this time New Zealand was apparently below (north of) the Polar Circle with a temperate and everwet climate.

This issue of Palaeogeography Palaeoclimatology Palaeoecology is devoted to papers on Mesozoic ecosystems and is an outcome of the International Geoscience Program (IGCP) 632. IGCP is a joint operation by UNESCO and the International Union of Geological Sciences (IUGS), which promote interdisciplinary Earth science research among scientists internationally. Since its formation in 1972, IGCP has supported over 500 projects in about 150 countries. 2015-04264 Utgör mass-utdöenden en driftkraft för evolutionen? Studier från krita-paleogengränsen Swedish Research Council 349-2007-8705 Lund University Carbon Cycle Centre (LUCCI)

A late Miocene (6–6.5 Ma; Kapitean and latest Tongaporutuan stages) fossil leaf locality is situated at Mataora in the southern Coromandel Peninsula of the North Island, New Zealand (latitude 37°S). It includes well-preserved remains of a new genus and species of conifer, Mataoraphyllum miocenicus, considered to be a phyllodinous Taxaceae. Other conifers include a new species of Phyllocladus, P. palmerii, and a small scale-leafed Podocarpaceae. There are five angiosperms, including a small-leafed Epacridaceae species, Myrsine waihiensis sp. nov., (Mysinaceae) Pseudopanax (Araliaceae), and two of unknown affinity. The relatively small leaf size, low biodiversity and taxonomic content suggest low, open vegetation under a relatively cool but wet climate; current subalpine to upper forest limit vegetation is a close analogy. The fossil assemblage indicates that mean annual temperatures may have been cooler at 37°S than today for the late Miocene.

Sapindaceae is one of the most important plant families in the warmer and, particularly, drier Australasian rainforests, but there are also representatives in more arid regions. The leaf cuticles of a representative selection of Australasian species of Sapindaceae are illustrated with transmitted light and scanning electron microscopy. The family exhibits a diverse range of characters, with no one feature being diagnostic. Four basic stomatal types can be recognized, but these grade between each other. Trichomes, glands and papillae are often present. A brief description of the epidermis of all genera in Australasia is given, and character combinations are discussed which may allow the identification of these in the fossil record. A rich cuticular fossil record in the early Miocene of New Zealand includes Alectryon and members of the tribe Cupanieae.

Mesofossil assemblages from several Cretaceous and Cenozoic units across Australia and New Zealand provide new evidence of insect and annelid behaviour. The earliest scale insects (Diaspididae, Coccoidea) from Australasia are described and represented by three scale morphotypes. The mesofossil assemblages also reveal clitellate annelid cocoon morphotypes, three morphotypes of arthropod coprolites and several insect piercement structures on gymnosperm leaf or stem fragments, possibly related to feeding or more likely oviposition. This research offers a new avenue for detecting cryptic terrestrial invertebrate groups and their interactions, particularly with plants, in the fossil record. The fossils demonstrate that insect/invertebrate activity can be preserved and identified in mesofossil suites, that such traces and exoskeleton fragments are relatively common in acid-extracted mesofossil suites, and that recognizable categories occur on multiple landmasses and at various ages.

This paper reports the discovery of three of the most iconic New Caledonian endemic genera, Amphorogyne, Paracryphia and Phelline, as dispersed leaf cuticle fossils in the early Miocene of New Zealand. New Caledonia's endemic angiosperm families have given it a reputation as one of the most interesting botanical regions in the world, but unfortunately it has no known pre-Pleistocene Cenozoic plant fossil record. A once more widespread distribution of its key plants in the context of a cooling and drying Neogene world suggests the current vegetation of New Caledonia is the result of contraction, or even a migration, from more southerly landmasses. Thus, New Zealand may have been a source of at least some of New Caledonia's plants.

M. S. Pole comments: In a recent paper Landis et al. (2008) propose that New Zealand was completely submerged in the Late Oligocene–earliest Miocene and therefore, its distinctive terrestrial biota must date from after that time. They propose this based on an analysis of the sedimentological, geomorphological and palaeontological record.

A fluvial sequence near Cave Stream (north of Castle Hill Village, central Canterbury), New Zealand, contains organically-preserved plant macrofossils (cuticles). The almost ubiquitous presence of Araucariaceae macrofossils in the lower part of the section and their stratigraphic disappearance roughly coincident with the appearance of the angiosperm leaf Dryandra comptoniaefolia and conifer taxa only known elsewhere from sediments of Paleogene age, indicates that the section spans the Cretaceous-Paleogene (K-T) boundary. This was subsequently confirmed by a palynological study that demonstrated the disappearance of Late Cretaceous index species within the investigated exposure. The sequence supports the pattern recognized elsewhere in New Zealand where Araucariaceae macrofossils either disappear or become very rare in end-Cretaceous and the leaf Dryandra comptoniaefolia is an important component in the early Cenozoic. The Cave Stream K-T boundary is one of the very few in the world with organically-preserved plant macrofossils and confirms the dramatic turnover in macroflora, which is known from North America. (C) 2009 Elsevier Ltd. All rights reserved. (Less)

New Zealand's Jurassic plant fossils are known from non-marine settings in two terranes: the Murihiku forearc basin and from a small area on the Rakaia Terrane, an accretionary prism. These terranes lay in relatively high latitudes along the Gondwana margin but their precise location, latitude and position with respect to each other is unclear. The flora was dominated by conifers, ferns, bennettitaleans, pentoxylaleans and locally equisetaleans, but it is relatively depauperate, perhaps reflecting a high latitude position. Most climate indicators suggest a warm temperate climate with rainfall that was not especially high and that might have been seasonal at times. Revision of the New Zealand Jurassic flora is overdue, and while new genera may be discovered, species numbers may well decrease.

Pole, M., December, 2008. The record of Araucariaceae macrofossils in New Zealand. Alcheringa 32, 405–426. ISSN 0311-5518. The Araucariaceae have a long record in New Zealand, extending back to the Jurassic at least, and Araucaria extends back to at least the Late Cretaceous. This paper reviews the macrofossil record of the family and presents new information based largely on the leaf cuticle record. Agathis, which is the only genus of the family currently growing in New Zealand, has no record before the Cenozoic. All specimens previously identified from pre-Cenozoic strata clearly belong to other taxa or do not show characteristic features of the genus. Araucariaceae macrofossils are virtually ubiquitous in the Cretaceous assemblages of New Zealand but are conspicuous by their absence or rarity in Palaeocene deposits. Their demise may be an expression of events at the Cretaceous–Palaeogene boundary.

A low-diversity Early Jurassic flora preserved in floodbasin siltstones of the Marburg Subgroup at Inverleigh Quarry in the Clarence-Moreton Basin, eastern Australia, is dominated by Allocladus helgei Jansson sp. nov., a conifer with denticulate leaves tentatively attributed to Araucariaceae. The assemblage also includes Rintoulia variabilis and Caytoniales, (Caytonia cucullata McLoughlin sp. nov. and cf. Sagenopteris nilssoniana), reinforcing the wide distribution of this order in Early to Middle Jurassic floras of Gondwana. Ferns (Cladophlebis and Sphenopteris species) and isoetalean lycophytes (Isoetites sp.) constitute the herbaceous elements of the flora. The palynoflora is dominated by cheirolepidiacean (Classopollis) pollen and is attributable to the upper part of the Corollina (=Classopollis) torosa Zone of late Pliensbachian-early Toarcian age (180-185 Ma). The Inverleigh flora represents one of the few Australian assemblages dated between the major phases of floristic turnover at the end of the Triassic and the Toarcian. Sedimentological characteristics, cuticular features of the conifer leaves and the abundance of free-sporing plants indicate a relatively humid palaeoclimate for the Clarence-Moreton Basin Early Jurassic. (Less)

The terrestrial biogeography of Gondwana during Jurassic-Early Cretaceous times is poorly resolved, and the flora is usually considered to have been rather uniform. This is surprising given the size of Gondwana, which extended from the equator to the South Pole. Documenting Gondwanan terrestrial floristic provincialism in the Jurassic-Early Cretaceous times is important because it provides a historical biogeographic context in which to understand the tremendous evolutionary radiations that occurred during the mid-Cretaceous. In this paper, the distribution of Jurassic-Early Cretaceous fossil wood is analysed at generic level across the entire supercontinent. Specifically, wood assemblages are analyzed in terms of five climatic zones (summer wet, desert, winter wet, warm temperate, cool temperate) established on the basis of independent data. Results demonstrate that araucarian-like conifer wood was a dominant, cosmopolitan element, whereas other taxa showed a greater degree of provincialism. Indeed, several narrowly endemic morphogenera are recognizable from the data. Finally, comparisons with Laurasian wood assemblages indicate strong parallelism between the vegetation of both hemispheres. (C) 2004 Elsevier B.V. All rights reserved.

The 40 km of coastline from Fortrose to Chaslands Mistake (southeastern South Island, New Zealand) comprises sediments that are part of the Early‐Middle Jurassic of the Murihiku Terrane. The sediments are dominantly fluvial with some marine beds and alluvial fan deposition, and display an evolution of fluvial style which progresses from perennial flow to seasonal flow. The McPhee Cove Conglomerate is a prominent unit to the north. It has been used to separate two formations which would otherwise, on inherent lithological grounds, be difficult to distinguish. This paper discusses several similar conglomerates which occur in the south, but which are separated from the type area of the McPhee Conglomerate by major tectonic disruption. Hence, the existing lithostratigraphic nomenclature to the north, including the McPhee Cove Conglomerate, cannot be simply extended southwards. The Fortrose‐Chaslands area appears to consist of two tectonic blocks, the Slope Point Block and the Brothers Block, which ar...

New Zealand has a good Neogene plant fossil record. During the Miocene it was without high topography and it was highly maritime, meaning that its climate, and the resulting vegetation, would be controlled dominantly by zonal climate conditions. Its vegetation record during this time suggests the climate passed from an ever-wet and cool but frostless phase in the Early Miocene in which Nothofagus subgenus Brassospora was prominent. Then it became seasonally dry, with vegetation in which palms and Eucalyptus were prominent and fires were frequent, and in the mid-Miocene, it developed a dry-climate vegetation dominated by Casuarinaceae. These changes are reflected in a sedimentological change from acidic to alkaline chemistry and the appearance of regular charcoal in the record. The vegetation then changed again to include a prominent herb component including Chenopodiaceae and Asteraceae. Sphagnum became prominent, and Nothofagus returned, but mainly as the subgenus Fuscospora (presently restricted to temperate climates). This is interpreted as a return to a generally wet, but now cold climate, in which outbreaks of cold polar air and frost were frequent. The transient drying out of a small maritime island and the accompanying vegetation/climate sequence could be explained by a higher frequency of the Sub-Tropical High Pressure (STHP) cells (the descending limbs of the Hadley cells) over New Zealand during the Miocene. This may have resulted from an increased frequency of 'blocking', a synoptic situation which occurs in the region today. An alternative hypothesis, that the global STHP belt lay at a significantly higher latitude in the early Neogene (perhaps 55degreesS) than today (about 30degreesS), is considered less likely because of physical constraints on STHP belt latitude. In either case, the difference between the early Neogene and present situation may have been a response to an increased polar-equatorial temperature gradient. This contrasts with current climate models for the geological past in which the latitude of the High Pressure belt impact is held invariant though geological time. (C) 2003 Elsevier Science B.V. All rights reserved.

Known Early-Middle Miocene terrestrial strata of southern New Zealand are represented by alluvial plain and lacustrine sediments. A vertebrate fauna including fish, ducks, and crocodiles populated Lake Manuherikia, with abundant mussels, gastropods, and stromatolites occupying the near-shore areas of the lake. A diverse vegetation covered the surrounding broad fluvial plains that extended to the coastal margins. Initially this was largely rainforest, which varied according to habitat and to changing climate. In particular, the climate and ecology appear to have fluctuated across the two major thresholds of fire/no-fire and of peat accumulation and no-peat. A major climate change, possibly the sharp global deterioration in conditions at about 14 Ma, profoundly changed the vegetation. Rainforest continuity fragmented, and herblands became widespread. Leaf fossils effectively disappear from the record at this time.

During the Middle Jurassic, the regional environment of Curio Bay, southeast South Island, New Zealand, was a fluvial plain marginal to volcanic uplands. Intermittent flashy, poorly-confined flood events buried successive conifer forests. With the termination of each flood, soils developed and vegetation was reestablished. In most cases, this developed into coniferous forest. In approximately 40 m of vertical section, 10 fossil forest horizons can be distinguished, highlighting a type of fluvial architecture which is poorly documented. Flood-basin material is minimal, but a short-Lived floodbasin lake is inferred to have developed within the interval of study. Paleocurrent indicators suggest enclosure of the basin on more than one side. Sedimentation style suggests a relatively dry (less than humid but not arid) climate with seasonal rainfall. (C) 2001 Elsevier Science B.V. All rights reserved.

Cycadophytes and ginkgophytes are frequent components of maceration residues in mid Cretaceous (Late Albian-Cenomanian) samples derived from bore cores within the Eromanga Basin, central Queensland, Australia. The material, from the Winton, Mackunda, and Allaru Formations, is in dispersed, fragmentary form, although some nearly intact leaves occur. Coniferous leaves dominate most samples. Bennettitaleans are represented by at least two species of Ptilophyllum, including P. boolensis and P. fasciatum. The Bennettitales documented are close to the end of their range in Australia. There is also one species of Pterostoma (Cycadales), P. hirsutus. Bennettitales were much more numerically important than Cycadales. Three species of Ginkgo are present: G. cf. G. wintonensis las abundant fragments), G. cf. G. australis, and G. cf. G. multiloba. A further cuticle type is suggested to belong to the Caytoniales or Cycadales. Chi-squared tests of association did not suggest any mutual exclusiveness amongst the taxa, but the Bennettitales showed a correlation with the presence of charcoal (suggesting fire-tolerance or pioneers after burning). (C) 1999 Academic Press.

A tidal platform at Curio Bay near the southernmost point of the South Island, New Zealand, preserves the petrified remains of an in situ Middle Jurassic forest. The forest grew close to the palaeo-polar circle, but data are not precise enough to tell on which side it lay. A mapped portion of the forest floor provides data on tree density and population structure, allowing comparison with recent forests and with records of other fossil forests. The forest has tree densities similar to many forests growing in low to mid-latitudes today; it appears to have had emergents projecting through a low canopy, and a well-developed undergrowth of smaller gymnosperms and osmundaceous ferns. No aspect of the forest structure uniquely distinguishes it from that of non-polar latitude forests. An extended discussion is given on reconstructing tree height from stump diameter. On the basis of this, a reinterpretation of the structure of an Early Cretaceous fossil forest from Alexander Island, Antarctica, is offered.

Two forms of monocotyledon macrofossil are documented from latest Albian-earliest Cenomanian sediments of the Eromanga Basin, central Queensland, Australia. One form is preserved as strap-shaped leaves with cross-linked parallel venation and epidermal features characteristic of monocots. Its affinities are suggested to be with the Areciflorae and it dominated a community lying between a coastal coal swamp and open marine conditions. A second form is found only as thin, dispersed cuticle, with poor detail, but is most likely also a monocot. It dominated a more inland community. These appear to be the currently known, oldest, organically preserved monocotyledonous macrofossils.

Twenty-seven angiosperm taxa and two conifers are described from the Van Diemen Sandstone of Melville Island, Northern Territory. The angiosperms include Brachychiloll, Grevillea, Melaleuca, and probable Cunoniaceae. The conifers are Araucaria and an unidentified genus of the Cupressaceae. Floristics and physiognomy suggest the climate was neither megathermal nor microthermal but that rainfall may have been seasonal. Two distinct assemblages are present, one from clay-rich mud, the other from sandier lithologies. The age of the Van Diemen Sandstone, which was probably deposited by a perennial sinuous river, is not known more precisely than Tertiary, but is suggested here to be Paleogene.

A quantitative palynostratigraphy is presented for the Manuherikia Group, New Zealand Six stratigraphic sections were studied from the northern Manuherikia basin where the relative proportions of six pollen taxa were compared Nothofagus ‘brassu type’, Nothofagus ‘fusca type’, Casuannaceae, Myrtaceae, Arecaceae, Asteraceae, and Chenopodiaceae A consistent order of dominance is apparent and zone boundaries are erected based on dominance of the latter five taxa over that of Nothofagus ‘brassu type’ Four new zones are proposed the Nothofagus ‘brassu type’ Zone, the Arecaceae‐Myrtaceae Zone, the Casuannaceae Zone, and the Asteraceae‐Chenopodiaceae Zone The latter is essentially a redefinition of the Chenopodipolhs chenopodiaceoides Zone of Mildenhall and Pocknall Correlation with the International time scale is attempted the N ‘brassu type’ Zone is Early Miocene, while the base of the Casuannaceae Zone or the Asteraceae‐Chenopodiaceae Zone may correlate with major global cooling recognised at approximately 14 Ma

Thirteen conifer macrofossils and a gymnospermous leaf of uncertain affinity are documented from the early‐mid Paleocene of the Mount Somers coal mine, Canterbury, New Zealand Podocarpaceae are prominent and diverse Two taxa are formally described as new genera of Podocarpaceae, Mumu somerensis gen et sp nov and Tiotio imbricatus gen et sp nov A second species of Kakahuta K drinnanu, is described There are also two species of Prumnopitys, P limaniae sp nov and P sp ‘Mt Somers’ A further five taxa of Podocarpaceae are informally described Shoots with decussately‐arranged scale leaves are identified as Libocedrus cf L bidwillii (Cupressaceae) Paahake papillatus gen et sp nov is compared with Sciadopitvs (Taxodiaceae) and Torreya (Taxaceae) A single small piece of cuticle belongs in the Araucanaceae and is tentatively identified as Araucana An additional new genus and species, Hoiki mcqueenu gen et sp nov , has an unusual epidemial morphology with transversely oriented stomates but is of unknown affinity The...

Eight genera of conifers in two or three families are documented from Miocene sediments of the Manuherikia Group, Central Otago, New Zealand They include Acmopyle masonu sp nov , Dacrycarpus dacrydioides Lepidothamnus intermedius, Podocarpus sp ‘Mata Creek’, Prumnopitys taxifoha, and Retrophyllum vulcanense in the Podocarpaceae, an indeterminate genus in either the Podocarpaceae or Taxaceae, and a single representative of the Cupressaceae Seven species occur in one deposit

A fish fossil of Miocene age from the Manuherikia group, from a site near Bannockburn in Central Otago, New Zealand, is described and identified as a galaxiid, probably genus Galaxias. The fish was large, estimated at 383 mm, and thus larger than all extant New Zealand Galaxias except G. argenteus, which is known to reach 580 mm. However, it appears to have been of quite slender form. There was, therefore, in Miocene times, a large, slender, perhaps lacustrine Galaxias in Palaeo‐lake Manuherikia in Central Otago.

An incomplete indeterminate crocodilian angular from the Miocene Bannockburn Formation, Central Otago, South Island, New Zealand is described. The fossil (probably a new taxon) represents the first undoubted occurrence of a crocodilian in New Zealand. Local palaeoclimatic indicators suggest the crocodilian lived in a temperate climate.

A new species of the mangrove palm Nypa, N. australis, is formally described from Lower Eocene sediments from near Strahan, western Tasmania. Fossil material comprises fronds (with cuticle), fruits, and pollen. Coming from a paleolatitude of approximately 65°S, it is the most polar Nypa known.

Twenty eight taxa of angiosperm fossils are described from the Early Miocene (c. 20 Ma) Foulden Hills Diatomite, not far from Dunedin, New Zealand. Some leaves include cuticle, and this has sometimes facilitated identification. Families confidently identified include Euphorbiaceae, Lauraceae, Myrsinaceae, Myrtaceae, Sapindaceae, and Smilacaceae, and, less confidently, Cunoniaceae and/or Elaeocarpaceae, Hernandiaceae, Leguminosae, Meliaceae or Rutaceae, Sterculiaceae, Tiliaceae, and Winteraceae. There is a notable absence of Nothofagus macrofossils, and only a single conifer, a broad‐leaved Podocarpus. The original community was probably moderately diverse and growing on a nutrient‐rich substrate. Floristics and climate were probably similar to northern New South Wales and southern Queensland today.