Early Palaeocene through early Eocene silicoflagellate assemblages were examined from five southern subtropical
through subpolar deep-sea sites: DSDP Holes 208 and 524, and ODP Holes 700B, 752A, and 1121B. For each
site, the taxonomic composition of the silicoflagellate assemblage is documented in detail; Pseudonaviculopsis
gen. nov., Dictyocha castellum sp. nov. and Stephanocha? fulbrightii sp. nov. are proposed, along with several
new combinations. More importantly, however, these observations enable a considerable refinement to the existing
Palaeocene–Eocene silicoflagellate biostratigraphic zonation that for the first time uses datums calibrated to
the Geomagnetic Polarity Timescale. The Corbisema aspera Interval Zone occurs immediately above the K/Pg
boundary and is here described from Seymour Island. The Corbisema hastata Partial Range Zone extends from
near the K/Pg boundary to late early Palaeocene and has been observed in Hole 208. The Pseudonaviculopsis disymmetrica
Acme Zone occurs in Holes 208 and 700B. The Dictyocha precarentis Partial Range Zone, observed
in Holes 208, 700B, 752A and 1121B, is subdivided into D. precarentis, Naviculopsis primativa, N. cruciata
and Pseudonaviculopsis constricta subzones. The Naviculopsis constricta Partial Range Zone occurs in Holes
524, 700B, 752A and 1121B. This study is also the first to consider syn- and/or diachroneity in Palaeogene
silicoflagellate biostratigraphy.
The organodetritic, sandy limestones of the Treskelodden Formation (Late Gzhelian to Early Artinskian) investigated in outcrops at Treskelen Peninsula, Hyrnefjellet mount and Polakkfjellet mount of south Spitsbergen, contain rich foraminiferal assemblages. Fifty eight foraminiferal species of twenty three genera, including two new species (Hemigordius hyrnefjelleti sp. nov. and Midiella arctica sp. nov.) have been identified. Three foraminiferal zones have been defined, with ages of Late Asselian (Pseudofusulinella occidentalis), Sakmarian (Midiella ovata – Calcitornella heathi) and Early Artinskian (Hemigordius hyrnefjelleti – Midiella arctica). Sedimentary features and the biotic history of the studied succession records a Late Paleozoic cooling trend that stays in accordance with Pangaea’s shift to the north.
Planktonie foraminifera of the genera Chiloguembelina Loeblich and Tappan. Globigerina d'Orbigny and Globorolalia Cushman are reported from glacio-marine sediments of the Low Head Member (Polonez Cove Formation, Oligocene) of King George Island (South Shetland Islands). West Antarctica. The foraminifer assemblage comprises two stratigraphically important species: Globigerina angiporoides Hornibrook and Chiloguembelina cubensis (Palmer), which indicate the Upper Eocene — Lower Oligocene age. Taking into account specific composition, this planktonie assemblage may tentatively be correlated with the Globigerina angiporoides Zone of New Zealand. Australia. South Pacific and South Atlantic, which belongs to the Lower Oligocene (see Jenkins 1985).
Sparse fish microremains have been found in marine limestones from the Middle Devonian (Givetian) Skały
Formation (Sitka Coral-Crinoid Limestone Member and Sierżawy Member), Świętomarz–Śniadka section,
Bodzentyn Syncline, Łysogóry Region, northern Holy Cross Mountains, associated with conodonts of the
hemiansatus to ansatus zones. Thelodont scales referred here to Australolepis sp. cf. A. seddoni come from near
Śniadka village, from samples dated as hemiansatus to rhenanus/varcus zones. This increases the known range
for the genus from its original find in Western Australia. The presence of a thelodont in the late Middle Devonian
in Poland extends the known distribution of turiniids around the peri-Gondwana shorelines of Palaeotethys.
The Silurian fishes from north-western Hunan, China are characterised by the earliest known galeaspids
Dayongaspis Pan and Zeng, 1985 and Konoceraspis Pan, 1992, and the earliest known antiarch Shimenolepis
Wang J.-Q., 1991, as well as rich sinacanth fin spines. Shimenolepis from Lixian County in north-western
Hunan, which was dated as the Telychian (late Llandovery), has long been regarded as the oldest representative
of the placoderms in the world. As such, in addition to eastern Yunnan and the Lower Yangtze Region,
north-western Hunan represents another important area in South China that yields important fossil material
for the research of early vertebrates and related stratigraphy. Here we summarise the Silurian fishes known in
north-western Hunan so far, and classify them into three vertebrate assemblages (i.e., the Wentang, Maoshan,
and Yangtze assemblages). Based on the updated Silurian vertebrate and stratigraphic databases, the Silurian
fish-bearing strata in north-western Hunan can be subdivided into the Rongxi, Huixingshao, and Xiaoxi formations
in ascending chronological order, which can be correlated with the Lower Red Beds, the Upper Red Beds,
and the Ludlow Red Beds in South China, respectively. A new look at the Silurian strata in Lixian suggests that
the age of Shimenolepis is late Ludlow rather than late Llandovery as previously suggested. The research on
Silurian fishes and biostratigraphy in north-western Hunan not only provides morphological data of early vertebrates,
but also offers new palaeoichthyological evidence for the subdivision, correlation, and age assignment of
the Silurian marine red beds in South China. The establishment of a related high-precision Silurian stratigraphic
framework in north-western Hunan will help to elucidate the temporal and spatial distribution of Silurian fossil
fishes, deepen the understanding of the evolution of early vertebrates, and unravel the coevolution between
Silurian vertebrates and the palaeoenvironment.
Shallow−marine deposits of the Krabbedalen Formation (Kap Dalton Group) from Kap Brewster, central East Greenland, yielded rich dinoflagellate cyst and pollen− −spore assemblages. Previously, this formation yielded also rich mollusc and foraminifer age−diagnostic assemblages. A Lower Oligocene age of the Krabbedalen Formation seems to be supported by the dinoflagellate cyst assemblage analysis, while the pollen−spore as− semblages point to a wider stratigraphic age range within Oligocene–Middle Miocene.
The lower (but not lowermost) part of the Upper Cretaceous Anaipadi Formation of the Trichinopoly Group in the area between Kulatur, Saradamangalam and Anaipadi, in the south-western part of the Cauvery Basin in southeast India yielded rich inoceramid and ammonite faunas. The ammonites: Mesopuzosia gaudama (Forbes, 1846), Damesites sugata (Forbes, 1846), Onitschoceras sp., Kossmaticeras (Kossmaticeras) theobaldianum (Stoliczka, 1865), Lewesiceras jimboi (Kossmat, 1898), Placenticeras kaffrarium Etheridge, 1904, and Pseudoxybeloceras (Schlueterella) sp., are characteristic of the Kossmaticeras theobaldianum Zone. The absence of Peroniceras (P.) dravidicum (Kossmat, 1895) indicates the presence of only lower part of this zone, referred to the nominative Kossmaticeras theobaldianum Subzone at the localities studied. The inoceramids present are Tethyoceramus madagascariensis (Heinz, 1933) and Cremnoceramus deformis erectus (Meek, 1877), recorded for the first time from the region. The latter dates the studied interval as early early Coniacian, and allows, for the first time, direct chronostratigraphic dating of the Tethyoceramus madagascariensis Zone, and consequently also of the Kossmaticeras theobaldianum Subzone. As inoceramids occur in the middle part of the ammonite-rich interval, the Kossmaticeras theobaldianum Subzone may be as old as latest Turonian and not younger than early early Coniacian. The base of the Coniacian lies in the lower, but not lowermost part of the Anaipadi Formation. Both inoceramids and ammonites represent taxa known from Madagascar and South Africa.
Triceratium barbadense Greville, 1861a, T. brachiatum Brightwell, 1856, T. inconspicuum Greville, 1861b and
T. kanayae Fenner, 1984a, are among the most common diatoms reported worldwide from lower to middle Eocene
biosiliceous sediments. Due to complicated nomenclatural histories, however, they are often confused. A morphometric
analysis performed herein indicates that T. brachiatum is conspecific with T. inconspicuum, and that both
were previously often misidentified as T. barbadense. Triceratium barbadense sensu stricto is a distinct species
similar to Triceratium castellatum West, 1860. Triceratium brachiatum and T. kanayae are transferred herein
to a new genus, Fenneria, for which a close phylogenetic relationship with Medlinia Sims, 1998 is proposed.
A review of the geographic and stratigraphic distribution of Fenneria shows that the best constrained records of
its occurrences are found at DSDP Site 338, and ODP Sites 1051 and 1260. The ages of the base (B) and top (T)
of each species’ stratigraphic range are calibrated here to the Geomagnetic Polarity Timescale either directly or
inferred via correlation with dinocyst biostratigraphy. Latitudinal diachroneity of ~7 million years is documented
for F. brachiata, which disappears earlier in tropical and mid-latitude sites than in the northern high latitudes. These
observations, coupled with a preliminary compilation of the Chron C20n taxonomic composition of pelagic diatom
assemblages for Sites 338, 1051 and 1260, indicate that diatoms diversified palaeobiogeographically considerably
earlier than the Eocene−Oligocene Transition, as commonly believed. This study also emphasizes the importance
of the detailed examination of specimens from both museum collections and deep-sea cores as a step toward enhancing
the utility of Palaeogene diatoms in palaeoceanographic and palaeoenvironmental reconstructions.
The radiolarian biostratigraphy of the Middle–Upper Jurassic pelagic siliceous sediments (Czajakowa Radiolarite
Formation) in the Niedzica succession of the Pieniny Klippen Belt (Carpathians) is interpreted in terms of their
age in a stratotype section, and facies equivalents in other tectonic-facies units of this region. The siliceous sediments
are represented by radiolarian cherts and silicified limestones which are underlain and overlain by red nodular
limestones, equivalents of the Rosso Ammonitico facies. The radiolarian association includes thirty-seven
taxa belonging to twenty one genera which represent the Northern Tethyan Palaeogeographic Province. Key radiolarians
recorded provide a means of correlation with zonation schemes based on Unitary Associations defined
for the Jurassic Tethyan sediments. The age of the Czajakowa Radiolarite Formation in the stratotype section
is determined as U.A.Z.9 to U.A.Z.11 corresponding to middle Oxfordian up to Kimmeridgian. Comparison of
radiolarian biozones from the stratotype section with other facial equivalent sections in the Pieniny Klippen Belt
reveals a significant diachronism for both the lower and the upper limits of the Jurassic pelagic siliceous facies.
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