Palynodinium | |
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Bright-field photomicrograph of Palynodinium grallator produced by Sandy McLachlan, University of Victoria from the Oyster Bay Formation of eastern Vancouver Island. | |
Scientific classification | |
Kingdom: | Chromista |
Superphylum: | Alveolata |
Phylum: | Myzozoa |
Superclass: | Dinoflagellata |
Class: | Dinophyceae |
Order: | Gonyaulacales |
Family: | † Areoligeraceae |
Genus: | † Palynodinium H.Gocht, 1970 |
Palynodinium is an extinct genus of organic-walled dinoflagellate cyst (or dinocyst). It is a fossil species of dinoflagellate cyst used to demarcate the K/Pg boundary, which marks the terminal Cretaceous and the extinction of the dinosaurs. [1] Palynodinium grallator was among the microfossils which lead to the recent discovery of the K/Pg event record in marine sediments of the northeast Pacific.
Dinoflagellate cysts are estimated to be produced by 10–16% of living dinoflagellates [2] [3] as a dormant, zygotic stage of their life cycle, which can accumulate in marine sediments as microfossils. Organic-walled dinoflagellate cysts are noted for their resistance to degradation owing to their composition of dinosporin, a biopolymer similar to sporopolinin characteristic of many terrestrial palynomorphs. [4] [5] Their abundance, cosmopolitan distribution, and quality of preservation in the fossil record since the Middle Triassic [6] [7] make dinoflagellate cysts excellent indicators of primary productivity [8] [9] as well as tools for biostratigraphy and paleoenvironmental reconstructions. [10] [11] The scope of dinoflagellate cyst applications has resulted in ongoing collaborative efforts between industry and academia to refine their taxonomic classification [12] and enhance their utility through database organization. [13]
Acritarchs are organic microfossils, known from approximately 1800 million years ago to the present. The classification is a catch all term used to refer to any organic microfossils that cannot be assigned to other groups. Their diversity reflects major ecological events such as the appearance of predation and the Cambrian explosion.
Palynology is the "study of dust" or of "particles that are strewn". A classic palynologist analyses particulate samples collected from the air, from water, or from deposits including sediments of any age. The condition and identification of those particles, organic and inorganic, give the palynologist clues to the life, environment, and energetic conditions that produced them.
Micropaleontology is the branch of paleontology (palaeontology) that studies microfossils, or fossils that require the use of a microscope to see the organism, its morphology and its characteristic details.
Chitinozoa are a group of flask-shaped, organic walled marine microfossils produced by an as yet unknown organism. Common from the Ordovician to Devonian periods, the millimetre-scale organisms are abundant in almost all types of marine sediment across the globe. This wide distribution, and their rapid pace of evolution, makes them valuable biostratigraphic markers.
A microfossil is a fossil that is generally between 0.001 mm and 1 mm in size, the visual study of which requires the use of light or electron microscopy. A fossil which can be studied with the naked eye or low-powered magnification, such as a hand lens, is referred to as a macrofossil.
The Campanian is the fifth of six ages of the Late Cretaceous Epoch on the geologic timescale of the International Commission on Stratigraphy (ICS). In chronostratigraphy, it is the fifth of six stages in the Upper Cretaceous Series. Campanian spans the time from 83.6 to 72.1 million years ago. It is preceded by the Santonian and it is followed by the Maastrichtian.
Dinocysts or dinoflagellate cysts are typically 15 to 100 µm in diameter and produced by around 15–20% of living dinoflagellates as a dormant, zygotic stage of their lifecycle, which can accumulate in the sediments as microfossils. Organic-walled dinocysts are often resistant and made out of dinosporin. There are also calcareous dinoflagellate cysts and siliceous dinoflagellate cysts.
The Sobral Formation is a palaeontological formation located in Antarctica. It dates to the Danian stage of the Lower Paleocene period.
Large ornamented Ediacaran microfossils are microscopic acritarchs, usually over 100 μm in diameter, which are common in sediments of the Ediacaran period, 635 to 538.8 million years ago. They largely disappear from the Ediacaran period fossil record before 560 million years ago, roughly coeval with the origin of the Ediacara biota. They differ from Palaeozoic microfossils in many respects; they are larger, often have internal contents, have a differently-constructed cell wall, and differ in shape.
Lingulodinium polyedra is a species of motile photosynthetic dinoflagellates. L. polyedra are often the cause of red tides in southern California, leading to bioluminescent displays on beaches at night.
Dinosporin is a macromolecular, highly resistant organic compound which forms or partly forms, the enclosing wall of fossilizable organic-walled dinoflagellate cysts.
Calcareous dinoflagellate cysts or calcareous dinocysts are dinoflagellate cysts produced by a group of peridinoid dinoflagellates, called calcareous dinoflagellates.
A hypnozygote is a resting cyst resulting from sexual fusion; it is commonly thick-walled. A synonym of zygotic cyst.
The Bull Run Formation is a Late Triassic (Norian) stratigraphic unit in the eastern United States. Fossil fish bones and scales have been found in outcrops of the formation's Groveton Member in Manassas National Battlefield Park. Indeterminate fossil ornithischian tracks have been reported from the formation.
Francisca Oboh-Ikuenobe is a geologist from Ubiaja in Esan South East Local Government Area of Edo State. She specialises in palynology and sedimentology, and is Professor of Geology in the Department of Geosciences and Geological and Petroleum and Engineering, and Associate Dean of Academic Affairs in the College of Engineering and Computing, Missouri University of Science and Technology.
The Cumnock Formation is a Late Triassic-age geologic formation in North Carolina. It is found in the of the Sanford sub-basin of the Deep River Basin, the southernmost of the large Mesozoic basins forming the Newark Supergroup. It is the middle unit of the Chatham Group, overlying the Pekin Formation and underlying the Sanford Formation. Both of these encompassing formations are primarily red sandstone. The Cumnock Formation, on the other hand, represents a sequence of darker lacustrine (lake) or paludal (swampy/marshy) sediments deposited in a tropical climate. These primarily include shales and coal, with some thin layers of coarser sediment such as siltstone and sandstone.
Circulisporites is a genus of plants. It is known from Triassic spores and pollen grains from the Ipswich coalfield in Queensland, Australia.
Dinosterane is a steroidal alkane, also known as 4α,23,24-trimethylcholestane. It is used in geochemistry as a biomarker, interpreted as an indication of dinoflagellate presence due to its derivative dinosterol high occurrence in extant dinoflagellate species and its rarity in other taxa, although it has been shown to be produced by a single species of marine diatom as well.
The Marne di Monte Serrone is a geological formation in Italy, dating to roughly between 181 and 178 million years ago, and covering the early and middle Toarcian stage of the Jurassic Period of central Italy. It is the regional equivalent to the Toarcian units of Spain such as the Turmiel Formation, units in Montenegro, such as the Budoš Limestone and units like the Wazzant Formation and the Azilal Formation of Morocco.
A protist is any eukaryotic organism that is not an animal, plant, or fungus. While it is likely that protists share a common ancestor, the last eukaryotic common ancestor, the exclusion of other eukaryotes means that protists do not form a natural group, or clade. Therefore, some protists may be more closely related to animals, plants, or fungi than they are to other protists. However, like algae, invertebrates and protozoans, the grouping is used for convenience.