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Palynofacies analyses from Bonyere Well No. 1 in the Tano basin, western Ghana has revealed five palynofacies associations (I – V) based on the percentage relative abundances of the sedimentary organic matter (SOM). The palynofacies associations reflect deposition in a fluvio-deltaic (oxic) environment, a distal dysoxic-anoxic shelf environment, a proximal dysoxic-suboxic environment, nearshore (oxic) and a fluvio-deltaic/nearshore environment with high oxygen levels and low preservation rates respectively. Based on marker palynomorphs, Campanian – Maastrichtian age has been assigned to sediments within the interval (1800-10 ft) – (90-100 ft), Turonian – Lower Senonian (Santonian) age between (3160-70 ft) – (1980-90 ft) and Aptian age between the interval (8140-50 ft) – (3340-50 ft). The absence of the elater-bearing pollen which are typical Africa-South America (ASA) elements for the Albian – Cenomanian age is indicative of an unconformity between the Aptian and Turonian sediments.
In the classic section across the Silurian–Devonian boundary at Dnistrove (Podolia, Ukraine) the brachiopod fauna has never been studied in detail. This paper presents results of research on brachiopods from this important locality and time interval. Bed−by−bed collecting has enabled the detailed distribution of brachiopod taxa through the boundary beds to be revealed. Generally, the reference section at Dnistrove yields rather scarce but often well preserved brachiopods. Dayia bohemica and Dnestrina gutta can be regarded as characteristic species for the uppermost Silurian. A relatively high−diversity but low−abundance brachiopod fauna occurs in the lowest 1.8 m of the earliest Devonian. Only three forms have been found to cross the Silurian–Devonian boundary: the strophomenide Plectodonta (Plectodonta) mariae pantherae subsp. nov., the atrypide Gracianella (Sublepida) paulula sp. nov., and the spiriferide Howellella (Howellella) latisinuata. A relatively narrow brachiopod−rich interval at 5.5 m above the Silurian–Devonian boundary yields 16 brachiopod species which probably indicate a setting near the lower limit of the photic zone equivalent to the Benthic Assemblage 3–4 boundary. Two new species and one new subspecies are described: Skenidioides tatyanae, Plectodonta (Plectodonta) mariae pantherae, and Gracianella (Sublepida) paulula.
Fragmentary long bone material from fossil Carnivora is rarely considered to support palaeoenvironmental reconstructions. Here, we use morphometry of the radius in extant carnivorans of the dog family (Canidae) to reconstruct the palaeobiology of extinct canids from Olduvai Gorge, Tanzania (Bed I and II) and Koobi Fora, Kenya. We use radius mor-phometrics to predict adaptation to prey size and introduce a new method for quantifying canid habitat adaptations based on the geographic distributions of the extant species sampled. Linear Discriminant Function Analyses (DFA) and cluster neighbour-joining algorithms are employed to investigate radial morphometrics as described by 29 linear measurements. Results of our analyses suggest that a phylogenetic signal is present in radial morphometrics, even if it does not allow us to accurately discriminate among genera. A binary prey size categorisation of "small-medium" versus "large" prey can be more accurately predicted than a habitat categorisation scheme (Open, Mixed, Closed). The East African fossil specimens examined show morphometric affinities with the golden jackal (Canis aureus) and coyote (Canis latrans) and are likely attributable to the genus Canis. Fragmentary fossil specimens from Olduvai Gorge are predicted as habitat generalists (Open for Bed I and Mixed for Bed II) adapted for hunting small-medium prey, whereas the specimen from Koobi Fora was predicted as inhabiting mixed habitats and adapted for killing large prey. This study supports the inclusion of fossil Canidae in palaeoecological analyses attempting to clarify the palaeoenvironment of early hominin fossil sites.
Trace fossils Lockeia siliquaria James, Ophiomorpha nodosa Lundgren, Para- taenidium seymourensis isp. n., Protovirgularia rugosa (Miller and Dyer) and Rhizo- corallium jenense Zenker have been described for the first time from the Eocene La Meseta Formation of Seymour (Marambio) Island, Antarctic Peninsula. Determinations of some trace fossils formerly described from this formation have been revised. The whole trace fossils association from the La Meseta Formation points to foreshore-offshore environment as indicated by presence of the Skolithos and Cruziana ichnofacies, and to at least temporal normal salinity.
We describe the first dinosaur skeletal remains found in the Czech Republic, consisting of one complete femur and indeterminable bone fragments. They were recovered from the upper Cenomanian near−shore marine sediments deposited on the slopes of an ancient archipelago, several kilometres north of the larger Rhenish−Bohemian Island that was situated in what is now the middle of Europe. Sediments yielding dinosaur remains are of late Cenomanian age, Inoceramus pictus–I. pictus bohemicusinoceramid zone of the local lithostratigraphic unit, the Peruc−Korycany Formation. These are the first uncontested dinosaurian fossils reported from this formation and also the first Cenomanian dinosaur record in Central Europe. They document a small ornithopod belonging to an iguanodontid species comparable with similar Late Cretaceous European forms. The herbivorous dinosaur lived among a vegetation transitional between salt marsh flora, with abundant halophytic conifer Frenelopsis alata; and an alluvial plain assemblage dominated by lauroid angiosperms.
Silurian land plants from the Holy Cross Mts. are described for the first time. The fossil assemblage occurs in a nearshore, marine, terrigenous deposit of Ludlowian/Pridolian age. It contains Cooksonia sp., Cooksonia−related species, and some problematical forms. The flora, which needs further study, is of importance to our understanding of early vascular plants and Late Silurian palaeogeography.
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Here we describe the first record of a chalicothere from the Miocene of Myanmar. The chalicothere, documented by a partial mandible, was unearthed from the lower portion of the Irrawaddy Formation in the region of Magway, Central Myanmar. The Burmese material belongs to an early late Miocene fauna which recently yielded hominoid remains attributed to Khoratpithecus. The specimen, which is attributed to a chalicotheriine, does not reliably match with any described Miocene Eurasian species of this subfamily, suggesting the possibility it belongs to a new taxon. The discovery of a chalicotheriine in the surroundings of Magway contributes to the hypothesis that closed habitats were an important component of the paleoenvironment of Khoratpithecus.
The radial trace fossil Dactyloidites peniculus occurs in a deep tier in totally bioturbated shoreface sediments of Pliocene age in the Stirone Valley, N Italy, together with Thalassinoides isp. and Ophiomorpha nodosa. Long, narrow shafts running from centre of the radiating structure and abundant faecal pellets in the radial structure were discovered. The trace maker of D. peniculus, probably a polychaete, deposited the pellets deeply in the sediment, probably for reinforcement of the tubes and a gardening of microbes for feeding. This trace fossil exclusively occurs within a narrow horizon at the top of a shallowing−up section interpreted as a high−stand system tract, below a discontinuity surface capped by finer sediments. D. peniculus was formed in soft sandy sediments under stable conditions related to the latest phases of the highstand system tract. Therefore, it is a candidate for indication of similar environmental situations having a soft sandy, but stable sea floor.
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