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1.
The Maslin Bay flora of South Australia is of lower Middle Eocene age and contains diverse, well preserved angiosperm assemblages. It has yielded 2700 specimens belonging to approximately 200 leaf taxa.

Physiognomic analysis (sensu Webb, 1959; Wolfe 1970) indicates greatest similarity to extant Simple Mesophyll Vine Forest and Complex Notophyll Vine Forest found currently in Queensland.

Preliminary taxonomic studies have confirmed the presence of taxa closely resembling Podocarpus (Podocarpaceae), Agathis (Araucariaceae), Fatsia (Araliaceae) and Banksia (Proteaceae). Microfloral analysis of the deposit confirms the presence of the latter three families, but suggests far greater occurrence of Proteaceae than the number of leaf specimens of this family indicates. Nothofagus pollen is the dominant type, although leaves of this genus are absent from collections. Based on sedimentation, physiognomy and systematic studies of leaves and fungi (Lange, 1969) it is concluded that the Maslin Bay region supported tropical to subtropical rain forest during the lower Middle Eocene.  相似文献   

2.
The Oligocene vegetation at Pioneer was closed temperate rainforest dominated by Nothofagus johnstonii Hill, which probably produced N. menziesii-type pollen. However, other angiosperms (Quintinia, Cupaniae, Ilex, Cunoniaceae, Myrtaceae, Proteaceae and Winteraceae) were also present, as well as several conifers (Athrotaxis, Phyllocladus, Podocarpus, Dacrydium, Dacrycarpus and Araucariaceae). This rainforest was floristically more complex that the modern Tasmanian Nothofagus cunninghamii rainforests but contained many taxonomically related elements. One major difference was that a fern similar to extant Cyathea filled the riparian niche now largely occupied by the tree-fern Dicksonia antarctica. There is indirect evidence that species producing Nothofagus brassii-type pollen may have occurred upstream of the site of deposition, suggesting that the Nothofagus species were altitudinally zoned or edaphically restricted. The current absence of many of these Nothofagus species in Tasmania may be due to their inability to survive the low temperatures of the Quaternary glaciations. The high degree of similarity of the Pioneer palynoflora to that recorded in Oligocene sediments in onshore (Partridge, 1971) and offshore (Stover &; Partridge, 1973; Stover &; Evans, 1973) Gippsland Basin strongly suggests that there was little regional differentation in southeastern Australia at that time.  相似文献   

3.
Four taxa of fossil leaves from Eocene strata at Maslin Bay, South Australia, are described with particular reference to architectural and epidermal features. Comparisons with extant and fossil taxa indicate that the families Podocarpaceae (Decussocarpus maslinensis sp. nov.), Proteaceae (Banksieaephyllum incisum sp. nov., Maslinia grevilleoides gen. et sp. nov.) and Araliaceae (Parafatsia subpeltata gen. et sp. nov.) are represented. The taxonomic affinities of the fossils support the interpretation of a wet, subtropical climate during the Middle Eocene in the Maslin Bay region.  相似文献   

4.
Examples of an undescribed species of the trilobite Redlichia from the Emu Bay Shale (Early Cambrian), Kangaroo Island, South Australia, show damage to the exoskeleton attributed to the action of predators. Injury was probably not lethal. The identity of the predators is unresolved, notwithstanding soft-part preservation within the fossil assemblage. Possible culprits include either a rare and presumably large animal such as an arthropod or conceivably cannibalism by Redlichia itself. This report provides new data on the occurrence of Cambrian predators, and casts further doubt on earlier suggestions that macrophagous predation was insignificant at this time. Aspects of trilobite predation during the Palaeozoic are reviewed, with emphasis placed on their ability to withstand substantial injuries and the possible repair mechanisms that promoted wound healing and survival.  相似文献   

5.
Microfossils which are hollow, possess a two-layered vesicle wall, and occur as single elements or, more rarely, as compound forms, have been recovered from the Early Cambrian Heatherdale Shale, on the Fleurieu Peninsula, South Australia. The microfossils, which range in size from 4 to 14.5 μm, are informally and tentatively assigned to the genus Sphaerocongregus Moorman 1974. Superficially they resemble forms assigned to Pyritosphaera Love 1958 and its probable junior synonym, Bavlinella Shepeleva 1962. Topotypes of these genera, however, have yet to be studied using SEM techniques, and their morphologic details remain uncertain. The organic composition of the present microfossils is supported by energy-dispersive X-ray analyses. Samples of the Heatherdale Shale were also analysed using pyrolysis techniques; the organic matter is, however, over-mature with respect to petroleum generation, and no geochemical assessment of original kerogen type is possible.  相似文献   

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This paper demonstrates and evaluates two different but complementary methodologies of small area forecasting in a rural area some 80 km north of Adelaide. The first approach forecasts overall population trends using a sector-by-sector appraisal of the growth/decline prospects of each economic sector based on detailed field surveys carried out in 1968 and 1970. The second approach was to use the readily available 1971 census and corresponding vital statistics data to project the population of the study area using a simple cohort-component projection methodology. Both approaches made forecasts of expected population levels by 1980, and in that year the authors conducted a resurvey of the same study area. The article demonstrates the need for, and results of, regular updating of the assumptions on which population forecasts are made, for the period 1968–1980 includedan unexpected revival of the farm economy as well as the onset of the international urban-rural migration flow of the ‘population turnaround’. Neither of these trends had been foreseen in the initial forecasts; their effects are shown in the results of the 1980 resurvey, and the utility of the forecasting methodologies is discussed in the light of these findings.  相似文献   

10.
The presence of two types of xiphodont crocodiles is reported for the first time from Australia. Crocodiles with this xiphoid type of tooth morphology were previously unknown anywhere in the world since the Miocene except for isolated xiphoid teeth noted by Plane (1967) from a Pliocene deposit in New Guinea.  相似文献   

11.
A monocotyledonous leaf macrofossil taxon from Golden Grove in Adelaide, South Australia is recognised as being close to several extant Australasian species of Cordyline, especially those in the C. stricta (Sims) Endl. / C. fruticosa (L.) A. Chev. complex. The fossil is assigned to the form genus Paracordyline, known previously from the Oligocene Kerguélen Islands. However, as the Golden Grove taxon differs markedly from the Kerguélen species, it is considered to be a new species, P. aureonemoralis Conran & Christophel.  相似文献   

12.
Zhuravlev, A. Yu., & Gravestock, D. I., 1994:03:28. Archaeayaths from Yorke Peninsula, South Australia and archaeocyathan Early Cambrian zonation. Alcheringa 18, 1–54. ISSN 0311-5518.

Two assemblages of archaeocyaths are documented from Lower Cambrian outcrops and drillholes on Yorke Peninsula. South Australia. The older assemblage (11 species) occurs in the uppermost Kulpara Formation and conformably overlying basal Parara Limestone, and is equivalent to Lower Faunal Assemblage II in the Flinders Ranges. The younger assemblage (28 species plus Acanthhcyathus and Rodiocyathus) occurs in the Koolywurtie Member near the top of the Parara Limestone. Equivalent taxa are widespread in the Flinders Ranges, western New South Wales and Antarctica. Archaeocyathan distribution is now sufficiently well known to propose three assemblage zones and two informal assemblages for regional correlation. No new taxa have been added, but Erugatocyathus scutatus (Hill) and Pycnoidocyathus latiloculatus (Hill), hitherto known only from Antarctica, are found in the upper assemblage on Yorke Peninsula. Irregular archaeocyathan systematics are discussed, the ontogeny of Archaeopharetra irregularis (Tylor) clarified, and Kruseicnema Debrenne. Gravestock & Zhuravlev, represented by K. gracilis (Gordon), is fully described.  相似文献   

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New forms of late Precambrian stromatolites are described from the Amadeus and Georgian Basins and additional information is given on Minjaria pontifera Walter from the Bitter Springs Formation. Tesca stewartii gr. et f. nov. is described from the Boord Formation, Elleria minuta gr. et f. nov. from the Pioneer Sandstone, and Tungussia julia f. nov. from the Julie Formation. The latter is compared with Tungussia cf. T. julia from the Wonoka Formation, South Australia. Acaciella australica Walter has been recognised in the Yackah Beds of the Georgina Basin, supporting a correlation with the Bitter Springs Formation. The stromatolites described were selected because of their potential regional and global stratigraphic significance.  相似文献   

15.
Hypolithic plants, plants growing under rocks, have been found from a number of climatically extreme, mostly arid sites from the poles to the equator, but there are limited reports from temperate zones. A brief survey in the Kosciuszko Alpine Area of New South Wales, Australia, revealed four species of moss and one liverwort growing beneath diaphanous quartz pebbles in feldmark vegetation communities. The probable restricted nature of this phenomenon and the likely impact of global warming, tourists and recreation management activities raise concerns for its conservation.  相似文献   

16.
Fossil eggshell fragments from a sand dune near Port Augusta are attributed to the extinct dromornithid, Genyornis newtoni Stirling & Zietz. Shell curvature measurements show that the eggs were larger than those of the Emu, Dromaius novaehollandiae. Radiocarbon dates indicate an age in excess of 40,680 BP. Holes pierced through some fragments are attributed to the action of predators.  相似文献   

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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.  相似文献   

19.
Yates, A.M., December, 2008. Two new cowries (Gastropoda: Cypraeidae) from the middle Miocene of South Australia. Alcheringa 32, 353–364. ISSN 0311-5518.

The South Australian specimens of the cypraeids Umbilia leptorhyncha (McCoy, 1877) and Lyncina (Austrocypraea) contusa (McCoy, 1877) are re-examined. Umbilia caepa sp. nov. differs from U. leptorhyncha in its smaller size, more strongly pyriform shape, weaker and less extensive apertural dentition, plate-like columellar margin of the posterior canal and more extensive basal flanges. True U. leptorhyncha is also recorded from the Cadell Formation of South Australia, demonstrating that the two species were sympatric in the Murray Basin. The specimens originally referred to Cypraea contusa var. from the Cadell Formation have had a confusing taxonomic history and they are here named as a new species Lyncina (Austrocypraea) cadella sp. nov. The new species differs from true L. (A.) contusa in its smaller size, less extensive malleations of the dorsal surface, fewer apertural teeth and a projecting internal margin of the fossula. These two new species boost a small but growing list of species that were endemic to the Murray Basin during the middle Miocene.  相似文献   

20.
Three new species of the Araucariaceae are described from leaf remains, Araucaria readiae from the Early Eocene Regatta Point flora, A. hastiensis from the Middle-Late Eocene Hasties flora, and Agathis tasmanica from the Early Oligocene-Early Miocene Little Rapid River flora. Additionally, emended diagnoses are presented for Araucarioides linearis and A. annulata. A. readiae is the first organically preserved species in the section Eutacta described from Tasmania, A. hastiensis is the first record of a species not in section Eutacta in Tasmania, and A. tasmanica is the first record of Agathis in Tasmania. These species, along with other records from south-eastern Australia indicate the presence of a high diversity of araucarian species in the region in the Early-Middle Tertiary, although no species survive there today. Climatic change and competition from angiosperms may have led to their demise in that region.  相似文献   

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