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1.
    
Falling trees commonly turbate soils in primary forest, creating characteristic edaphic patterns related to pit and mound topography. Vernal ponds with associated mounds were observed in mineral soils on a treeless plain in subalpine Tasmania, Australia. The hypothesis that paired ponds and mounds on the plain originated as pit and mound features in forests that were later destroyed by fire was tested by comparing the soils and landforms caused by recent tree falls in adjacent forest with those on the plain. The soil characteristics, orientations, and dimensions of the ponds and mounds were consistent with a tree fall origin, although rare secondary ponds on the tops of mounds may derive from the burrowing activities of the medium‐sized marsupial, Vombatus ursinus (common wombat). The characteristics of pond and mound soils suggested that most were hundreds to thousands of years old, with the ponds persisting because of differences in deflation, deposition, and organic matter formation between themselves and adjacent persistently dry land.  相似文献   

2.
    
Continental deposits of the Cullen Formation (early or middle Miocene) exposed on the northeast coast of Isla Grande de Tierra del Fuego (southernmost Patagonia) are analyzed. Twenty-four taxa of algae, and bryophyte and pteridophyte spores are identified, including three new species, which are Anthocerisporis gandolfii sp. nov., Coptospora archangelskyi sp. nov. and Ophioglossisporites cullensis sp. nov. Sedimentologic and palynological data suggest a system of meandering water channels. The diverse and abundant spore assemblage reinforces the proposed paleoenvironment indicated by pollen assemblage and stratigraphy, consisting of humid temperate forests and local occurrences of bog, freshwater and near-shore lake communities.  相似文献   

3.
    
Seven species of marine bivalves, including six new taxa, are described from the Cape early Miocene Melville Formation which crops out on the Melville Peninsula, King George Island, West Antarctica. The bivalve assemblage includes representatives of the families Nuculidae, Ennucula frigida sp. nov., E. musculosa sp. nov.; Malletidae, Neilo (Neilo) rongelii sp. nov.; Sareptidae, Yoldia peninsularis sp. nov.; Limopsidae, Limopsis psimolis sp. nov.; Hiatellidae, Panopea (Panopea) sp. cf. P. regularis; and Pholadomyoida (Periploma acuta sp. nov.). Species studied come from four sedimentary sections measured in the upper part of the unit. Detailed morphologic features of nucloid and arcoid species are exceptionally well preserved and allow for the first time reconstruction of muscle insertions as well as dentition patterns of Cenozoic taxa. Known geological distribution of the species is in agreement with the early Miocene age assigned to the Cape Melville Formation. The bivalve fauna from Cape Melville Formation is the best known from Antarctic Miocene rocks, a time of complex geologic, paleogeographic and paleoclimatic changes in the continent. The new fauna introduces new taxonomic and palaeogeographic data that bear on the question of opening of sea gateways and distribution of Cenozoic biota around Antarctica.  相似文献   

4.
Vijaya, Prasad, G.V.R. & Singh, K., June, 2009. Late Triassic palynoflora from the Pranhita–Godavari Valley, India: evidence from vertebrate coprolites. Alcheringa 33, 91–111. ISSN 0311-5518.

The Upper Triassic Maleri Formation, represented by red clays and sandstones, has to date not produced any plant macrofossils or palynomorphs. Many spiral and non-spiral coprolites collected during this study from the Maleri Formation of the Pranhita-Godavari Valley were analysed for palynomorphs. Based on shape, nature of coiling and size, the Maleri coprolites are classified into seven groups. Of these, only Group-I, Type 5 (non-spiral) and amphipolar (spiral) types yielded diverse gymnospermous and pteridophytic spores, pollen, other plant debris and sparse fungal spores and algal remains. Occurrences of Antulsporites varigranulatus, Aratrisporites spp., Cadargasporites baculatus, Dubrajisporites isolatus, Enzonalasporites vigens, Foraminisporis coelatus, Grandispora spinosa, Kraeuselisporites saeptatus, Polycingulatisporites reduncus, Staurosaccites spp., Tethysispora unica and Tikisporites balmei confirm a Late Triassic age for the coprolite-bearing red clays. Records of Classopollis classoides and Callialasporites turbatus/dampieri in these assemblages more precisely suggest a Norian to Rhaetian age. The non-spiral coprolites were possibly produced by aquatic piscivorous animals whereas the spiral coprolites may have been produced by an as yet unidentified fish taxon. The coprolite-producing animals (spiral and non-spiral groups) possibly ingested gymnospermous and pteridophytic plant remains passively along with water or their herbivorous prey.  相似文献   

5.
Peng, J., Li, J., Slater, S.M., Li, W., Zhu, H. & Vajda, V. October 2017. Triassic palynostratigraphy and palynofloral provinces: evidence from southern Xizang (Tibet), China. Alcheringa 42, 67–86. ISSN 0311-5518.

Palynological analysis was carried out on Middle to Upper Triassic strata from Tulong, Nyalam County, southern Xizang (Tibet), China. Well-preserved miospore (pollen and spore) assemblages and sparse acritarch occurrences were identified. We recognized four formal and one informal biozones based on stratigraphically important taxa and compositional changes through the succession, in ascending order: the Triplexisporites Interval Zone (Anisian), the Staurosaccites quadrifidus Taxon-range Zone (upper Anisian to lower Norian), the Striatella Interval Zone (lower Norian), the Craterisporites rotundus Taxon-range Zone (middle to upper Norian) and the informal ‘Dictyophyllidites harrisii zone’ (Rhaetian). The zonation was supported by marine fossils (e.g., ammonoids and conodonts), and compositional similarity between the zones was examined using non-metric multidimensional scaling (NMDS). Correlation with other representative palynological sequences across Gondwana was also conducted. The presence of miospore taxa not previously recovered from the Late Triassic North and South China palynofloral provinces (e.g., Ashmoripollis reducta, Craterisporites rotundus, Enzonalasporites vigens, Minutosaccus crenulatus, Samaropollenites speciosus and Staurosaccites quadrifidus) calls for a new province in southwestern China, i.e., the Southern Xizang Province. It is proposed here that the modern expression of the northern boundary runs along the Yarlung Zangbo Suture, the remnant of the Tethys that separated the Indian Plate (southern Xizang) and the Lhasa Block during the Late Triassic. This new palynofloral province comprises typical elements of the Onslow Microflora, indicating the need for an extension of this microflora in southern Xizang, China.

Jungang Peng [], Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China, University of Chinese Academy of Sciences, Beijing 100049, China, Department of Palaeobiology, Swedish Museum of Natural History, Stockholm 104 05, Sweden; Jianguo Li* [], Key Laboratory of Economic Stratigraphy and Palaeogeography, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China; Wenben Li [], Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China; Sam M. Slater [], Vivi Vajda [], Department of Palaeobiology, Swedish Museum of Natural History, Stockholm 104 05, Sweden; Huaicheng Zhu [], State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China.  相似文献   


6.
    
Fossil Elaeocarpus species with spherical fruits are redescribed and compared with extant species. Information on the distribution of E. mackayi (F. Muell.) Kirchheimer and E. spackmaniorum Rozefelds is provided. Additional notes on the morphology of E. spackmaniorum Rozefelds are also included; and collections from Guildford, in Victoria, are considered conspecific. Elaeocarpus occultus sp. nov. is described from the Haddon deep leads in Victoria; it has a spherical inner mesocarp, bastionate ornamentation, foraminae in the mesocarp wall and mesosutural ridges, which represent a combination of characters unique within extant Australian Elaeocarpus species. The fossil fruit record of Elaeocarpus is systematically significant because it demonstrates that the genus was morphologically diverse by the Miocene in Australia. Biogeographically, the genus also had a different, or more widespread distribution in Australia during the Cenozoic.  相似文献   

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