Jan Ove R. Ebbestad

Jan Ove R. Ebbestad
Uppsala University | UU · Museum of Evolution

PhD

About

164
Publications
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1,251
Citations
Additional affiliations
June 2007 - present
Uppsala University
Position
  • Curator

Publications

Publications (164)
Article
Full-text available
The Digermulen Peninsula in northeastern Finnmark, Arctic Norway, comprises one of the most complete Ediacaran–Cambrian transitions worldwide with a nearly continuous record of micro- and macrofossils from the interval of the diversification of complex life. Here, we report on the provenance and post-depositional alteration of argillaceous mudstone...
Article
Full-text available
New acritarch data from the Kistedalen Formation based on two sections with continuous exposure enable us to establish the most detailed Miaolingian acritarch biozonation in Baltica to date. Six interval zones previously established in Gondwana, the Eliasum llaniscum, Cristallinium cambriense, Adara alea, Timofeevia lancarae, Cristallinium dubium a...
Conference Paper
A new bradoriid fauna comprising seven taxa is introduced from the early Cambrian Skyberg Member of the Ringstrand Formation of the Mjøsa area in Norway. The fauna is compared to coeval specimens described from Sweden (Wiman 1903), which have been restudied for this study. Both faunas comprise the same, or similar, genera of the families Bradoriida...
Conference Paper
Molluscs, present and past, are second only to arthropods in abundance, diversity, morphological disparity from the shell-less to the multi-shelled, and in environmental adaptations. While monophyly of extant molluscan classes is accepted, the relationship within these are unclear and even the origin of the group itself is murky. Possible Ediacaran...
Article
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New occurrences of flask-shaped and envelope-bearing microfossils, including the predominantly Cambrian taxon Granomarginata, are reported from new localities, as well as from earlier in time (Ediacaran) than previously known. The stratigraphic range of Granomarginata extends into the Cambrian System, where it had a cosmopolitan distribution. This...
Article
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Sabellidites cambriensis is a tubular non-mineralized metazoan that appears as compressed ribbon-shaped imprints with transverse wrinkling, thick walls and an even tube diameter of up to 3 mm. The distribution of Sabellidites is investigated in three Ediacaran–Cambrian sections on the Digermulen Peninsula in Arctic Norway, spanning the Manndrapselv...
Article
An Early Ordovician fauna of linguliform brachiopods and euconodonts is described from the Alum Shale Formation in northernmost Västerbotten County, northern Sweden. The fauna was recovered from a single carbonate concretion collected at an exposure near the northern shore of Lake Storvindeln. Despite of the fragmentary and tectonized preservation...
Article
More than 30 species of tergomyan, gastropod, bivalve and cephalopod molluscs are described from the Late Ordovician of central and eastern Anti-Atlas, Morocco. For the cephalopods this represents the first systematically known taxa of the region. Tergomyans and gastropods are most common in the more shaly part of the Lower Ktaoua Formation, while...
Book
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During his nearly three years in China, the Austrian-Swedish palaeontologist Otto Zdansky (1894–1988) made pioneering discoveries of fossil faunas that greatly enhanced the understanding of the evolution of Chinese vertebrates. The most important was found in 1921 during his very first field trip in the country, to Zhoukoudian outside Beijing, wher...
Article
New information on acritarchs from the Duolbagáisá Formation, Digermulen Peninsula, Arctic Norway, enable recognition of the three Cambrian Series 2 acritarch-based zones: the Skiagia ornata – Fimbriaglomerella membranacea , Heliosphaeridium dissimilare – Skiagia ciliosa and Volkovia dentifera – Liepaina plana Assemblage z ones. Acritarchs of the S...
Article
A new occurrence of the onychochilid mollusc Pelecyogyra is reported from the late Floian Landeyran Formation (Apatokephalus incisus Biozone) in the Montagne Noire, southern France, where it is associated with the two tergomyans Carcassonnella courtessolei and Thoralispira laevis, and a mollusc indet. With a low cap-shaped shell. The Montagne Noire...
Article
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A new sinistrally coiled univalved mollusk Catalanispira n. gen. is described with two species; Catalanispira reinwaldti (Öpik, 1930) from the Middle Ordovician Kõgekallas Formation (Darriwilian) of Estonia and Catalanispira plattevillensis n. gen. n. sp. from the Upper Ordovician Platteville Formation (Sandbian) of northern Illinois, USA. Morpholo...
Article
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A new rare Upper Ordovician mound dwelling palaeoloricate chiton is described as Crassaplax collicola gen. et sp. nov. from three large isolated intermediate valves from the Katian carbonate mud mounds of the Boda Limestone in the Siljan district of central Sweden. Together with the previously known Spicuchelodes? sp., also from the Boda Limestone,...
Article
Analysis of mushroom‐shaped rugose corals Schlotheimophyllum patellatum (Schlotheim, 1820) from the Silurian (Upper Visby Beds, Lower Wenlock, Sheinwoodian) of Gotland, Sweden, showed that they were colonized on both the upper (exposed) and lower (cryptic) sides by a variety of encrusting and boring (sclerobiont) biotas, represented by 10 taxa and...
Article
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Results of in situ U–Pb dating of calcite spherulites, cone-in-cone (CIC) calcite and calcite fibres from a calcareous concretion of the upper Ediacaran of Finnmark, Arctic Norway, are reported. Calcite spherulites from the innermost layers of the concretion yielded a lower intercept age of 563 ± 70 Ma, which, although imprecise, is within uncertai...
Article
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Jinonicella kolebabai Pokorný, 1978, a small problematic "mollusc" of unknown origin is described from the early Silurian (early to mid Llandovery) of east Siberia. This is the first record of Jinonicella from Siberia. Previous Silurian records of Jinonicella were from the late Llandovery (Telychian) of North America and the Wenlock to Ludlow of Eu...
Article
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Ordovician trilobites from the important sequences of the Taimyr Peninsula, Arctic Russia have been poorly studied since the work by Balashova (1959 Balashova, E. A. 1959. Middle and Upper Ordovician and Lower Silurian trilobites of eastern Taimyr and their stratigraphic significance. Sbornik Statej po Paleontologii i Biostratigrafii, 14, 17–47, 6...
Article
Phragmolites lissoni new species is described from 11 specimens found in the Sandbian Calapuja Formation near Calapuja in Peru. The deposits are part of the Central Andean Basin. This is the hitherto only systematically described Ordovician gastropod from Peru. The species is from a brachiopod-dominated siliciclastic sequence and is associated with...
Article
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Eukaryotic multicellularity originated in the Mesoproterozoic Era and evolved multiple times since, yet early multicellular fossils are scarce until the terminal Neoproterozoic and often restricted to cases of exceptional preservation. Here we describe unusual organically-preserved fossils from mudrocks, that provide support for the presence of org...
Article
Eukaryotic multicellularity originated in the Mesoproterozoic Era and evolved multiple times since, yet early multicellular fossils are scarce until the terminal Neoproterozoic and often restricted to cases of exceptional preservation. Here we describe unusual organically-preserved fossils from mudrocks, that provide support for the presence of org...
Article
Full-text available
Fine-fraction K‒Ar dating and illite crystallinity determination were applied on a peculiar pale olive green shale sample from the upper Ediacaran Indreelva Member (Stáhpogieddi Formation, Vestertana Group, Gaissa Nappe Complex) of the Digermulen Peninsula in Finnmark, Arctic Norway, to constrain the age and metamorphic conditions of tectono-therma...
Conference Paper
Full-text available
The Neoproterozoic-Cambrian succession in the remote Digermulen Peninsula of the Tanafjorden area in eastern Finnmark, northern Norway, has attracted renewed research interest because of new findings of Ediacaran- aged fossils (e.g. Jensen et al., 2018, Canadian Journal of Earth Sciences). Hitherto, the entire upper Ediacaran and Cambrian successio...
Article
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The olenellid trilobite Holmia cf. mobergi, known from a single cephalon in the upper lower Cambrian strata from a river section in Flagstadelva, Hamar, has played a significant stratigraphic role in interpreting the lower Cambrian informal Series 2, Stage 3 in the Mjøsa area, Norway, since its discovery in the early 1950s. It was considered one of...
Conference Paper
Full-text available
Climatic variations that significantly impact weathering rates are directly reflected in the Os istopic composition of seawater, either locally or globally. Thus, 187Os/188Os ratios preserved in organic-rich sedimentary rocks archive climatic variations in the geologic record. The lower Paleozoic has relatively few constraints, despite the importan...
Conference Paper
Important occurrences of Late Ordovician trilobites of the Taimyr Peninsula, Arctic Russia have been known for nearly 70 years through the work of Balashova (1959/1960) but have been neither well-understood nor revised. A study and revision of 56 Sandbian-Katian species from the Peninsula, including new and previous described material, gives a clea...
Article
The strata of Gotland, Sweden, provide one of the richest records of Silurian gastropod faunas in the world. Recent re‐evaluation of museum collections revealed for the first time the presence of gastropods of the superfamily Porcellioidea (Archaeogastropoda) in the Silurian strata of Gotland (Baltica). Additionally, the porcellioideans from Gotlan...
Article
The Taimyr Peninsula is rich in Ordovician trilobites, some of which were described by E. A. Balashova nearly sixty years ago; these have now been supplemented by new collections. We here describe the Ordovician formations from which trilobites have been recovered in the light of much subsequent fieldwork elucidating the regional geology. Late Ordo...
Article
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Centropleurid trilobites include five genera of which Centropleura Angelin, Anopolenus Salter, Clarella Howell and Luhops Šnajdr are known from eight species in the traditional middle Cambrian (Miaolingian Series, Drumian Stage) of Sweden and Denmark (Bornholm). Beishanella Xiang & Zhang has not been recorded in Scandinavia so far, and no centrople...
Conference Paper
Full-text available
The remote Digermulen Peninsula by the Tanafjorden of north-eastern Finnmark, Arctic Norway, contains an almost complete sedimentary record across the Ediacaran–Cambrian transition as well as microfossils, macrofossils and trace fossils for studying the Ediacaran biota and the Cambrian radiation. It is one of the few localities worldwide and the on...
Article
We report on new occurrences of the late Ediacaran problematicum Palaeopascichnus (Protista?) from the Stáhpogieddi Formation, Arctic Norway. The stratigraphically lowest occurrences are in beds transitional between the Lillevannet and Indreelva members: the highest in the second cycle of the Manndrapselva Member, stratigraphically close to the low...
Article
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Scratch circles – bedding plane parallel sedimentary structures formed by the passive rotation of a tethered organism into the surrounding sediment – are relatively rare in the geological record. Here new occurrences of scratch circles are described from the Ediacaran–Cambrian Stáhpogieddi Formation, Digermulen Peninsula, Arctic Norway, and from th...
Conference Paper
The thick Late Ordovician (Katian) succession on the Taimyr Peninsula, Arctic Russia is divided into three regions showing a transition from a southern carbonate dominated facies, a central transitional facies, and a siliciclastic dominated northern facies. All regions are rich in trilobites but hitherto only the southern fauna was described. New c...
Conference Paper
Full-text available
The lower Cambrian sequence on the Digermulen Peninsula (Finnmark, Arctic Norway) is the northernmost extension of the Cambrian deposits along the Caledonian front. It is exceedingly thick compared to cratonal successions typical of most of Baltica. The Duolbagáisá Formation represents the youngest lower Cambrian unit on the peninsula with the firs...
Article
Full-text available
The small enigmatic mollusc Jinonicella kolebabai Pokorný, 1978 is described from the upper Silurian Cardiola Formation at the Rauchkofel Süd section of the Carnic Alps, Austria. The associated conodonts suggest a late Ludlow (Ludfordian) Polygnathoides siluricus conodont Zone. Previous Silurian records of Jinonicella are known from the Wenlock to...
Article
The hyolith assemblage from the early Cambrian of Bornholm, Denmark, shows a higher diversity than contemporary assemblages in Baltoscandia. The most common species in the Green Shales (Læså Formation, Norretorp Member, Cambrian Stage 3), is Hyolithes [=Hyolithus] (Orthotheca) johnstrupi Holm, 1893. A specimen of this species shows a well-preserved...
Article
The Lower Ordovician Bjørkåsholmen Formation at Flagabro, Scania, southern Sweden, consists of a 0.8 m thick succession of carbonates with three siliciclastic mudstones, 5, 1 and 100 mm thick, intercalated in the central part of the unit. Carbonate and siliciclastic mudstone beds show both normal and inverse grading. The carbonates are mud-rich and...
Article
Four teeth of Peking Man from Zhoukoudian, excavated by Otto Zdansky in 1921 and 1923 and currently housed in the Museum of Evolution at Uppsala University, are among the most treasured finds in palaeoanthropology, not only because of their scientific value but also for their important historical and cultural significance. It is generally acknowled...
Article
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This paper describes 3 species of ribeirioid and 2 species of conocardiid rostroconchs from fluvially transported erratic in the Dutch-German border area. The material probably stems from Ordovician deposits of the North Estonian Confacies Belt. The ribeirioid specimens from the Haljala group of erratics (Sandbian 2) are represented by Tolmachovia...
Conference Paper
Lower Cambrian holmiid olenelloids are used for biozonation of lower Cambrian (Series 2) strata in Baltoscandia. About a dozen species have been named since the description of Holmia kjerulfi (Linnarsson, 1868), but except for the classical area in Mjøsa, Norway, the species traditionally occur in small numbers, are variably preserved, occur at one...
Conference Paper
Ordovician and Silurian trilobites from the Taimyr Peninsula were described by Balashova (1959, 1960), who identified 31 genera and 60 species through the Middle and Upper Ordovician part of the succession. New material from the Ordovician succession was collected during a multidisciplinary expedition arranged by the Swedish Polar Research Institut...
Conference Paper
Full-text available
The Digermulen Peninsula, Arctic Norway, contains one of the most complete Ediacaran–Cambrian sedimentary rock successions on Baltica. The boundary interval spans the Manndrapselva Mbr of the Stáhpogieddi Fm. and the Lower Mbr of the Breidvika Fm. Abundant organic-walled microfossils (OWM) and organic fossils (OF) in the second and third cycles of...
Conference Paper
Full-text available
The Digermulen Peninsula, Arctic Norway, contains one of the most complete Ediacaran–Cambrian sedimentary rock successions on Baltica. The boundary interval spans the Manndrapselva Mbr of the Stáhpogieddi Fm. and the Lower Mbr of the Breidvika Fm., consisting of several coarsening upward cycles, each less than 100 meters thick, dominated by mudston...
Conference Paper
Full-text available
Exposed on the Digermulen Peninsula in northernmost Norway is possibly the most complete Ediacaran–Cambrian succession in Baltica, as well as being the only Scandinavian locality preserving Ediacara-type fossils. The Peninsula exhibits a late Neoproterozoic to Lower Ordovician succession consisting of roughly 3000 m of siliciclastic deposits formed...
Article
Ei internasjonal forskergruppe har gjennom fem sesonger arbeidet på Digermulhalvøya i Vestertana, Finnmark og gjort oppsiktsvekkende fossilfunn. Dette dreier seg om intet mindre enn fossiler fra dyrerikets spede begynnelse og vil være med på å bidra til forståelsen av dyrerikets opprinnelse og evolusjon. Noen av de tidligste, flercellede organismen...
Conference Paper
The late Neoproterozoic Nyborg Formation is exposed in the Tanafjord area, Finnmark, Arctic Norway, on Digermulen and Varanger Peninsulas. The succession is composed of ~400 m of interbedded shales, siltstone and purple to grey sandstone, deposited between Neoproterozoic low latitude glacial deposits. The Nyborg Fm. lies on top of the Smalfjord dia...
Article
The small problematic mollusc Jinonicella kolebabai Pokorný, 1978 is described from the lower Silurian Laketown Dolostone at Barn Hills in Utah, USA. The associated conodonts suggest a late Telychian age for the assemblage, which makes this the oldest occurrence of this species. Previous Silurian records of Jinonicella were known from the Sheinwood...
Article
Pterotheca hispanica nov. sp. is described from the basal beds (Stimulograptus sedgwickii graptolite Zone) of the Formigoso Fm., in the Cantabrian Zone of the Iberian Massif, north-western Spain. This specialized bellerophontoid gastropod is for the first time recorded in the Silurian of peri-Gondwana; it is the only Aeronian species known so far....
Article
The Late Ordovician Period witnessed the second largest mass extinction in the Phanerozoic Eon and the Hirnantian glaciation. To infer ocean redox conditions across the Ordovician-Silurian transition, we measured the U (as δ²³⁸U relative to standard CRM145 = 0‰) and Mo (as δ⁹⁸Mo relative to standard NIST SRM 3134 = + 0.25‰) isotope compositions of...
Article
Pengia Geyer & Corbacho is a Cambrian burlingiid trilobite with fused trunk segments devoid of any articulation in the anamorphic and epimorphic phases of development. The type species is Pengia fusilis (Peng et al.) from the Wanshania wanshanensis Zone of China. Here we describe a second species, Pengia palsgaardia sp. nov., from the Lejopyge laev...
Conference Paper
Fossils record evolutionary processes, biotic turnovers and major transitions in the Earth system history. Transitions may be abrupt or gradual, but their study depends often on the quality and extension of the material or sections available. The Digermulen Peninsula is one of few places in the world where a more or less continuous succession recor...
Article
The near planispiral euomphaloid gastropod Lesueurilla prima (Barrande in Perner) is a typical part of the cold water Mediterranean fauna in the Lower and Middle Ordovician. It is a signature species in strata of this age in the Prague Basin in the Czech Republic, Montagne Noire in France, and Central Morocco. The species is reported for the first...
Article
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This paper describes the morphology and discusses the taxonomy of the paradoxidid trilobites present in the moult ensemble described by Ebbestad et al. (2013) from a huge limestone concretion of the Alum Shale Formation collected at Östnår, Jämtland. Two species, both represented by numerous but small complete holaspid specimens are described as ne...
Article
A previously undocumented diversity of Cambrian palaeoscolecids is described from localities in Sweden, Norway and Denmark. The material described here includes isolated sclerites as well as the first macroscopic specimens reported from the palaeocontinent Baltica. The sclerites are all of early middle Cambrian age (Ptychagnostus gibbus Biozone) an...
Conference Paper
Full-text available
The Digermulen Peninsula in northern Norway is the only fossiliferous site in Scandinavia with sedimentation across the Ediacaran–Cambrian transition without a significant hiatus. Furthermore, it is the only locality in Scandinavia where Ediacara-type fossils have been found. The site is located at the edge of Baltica during the Ediacaran–Cambrian...
Article
Late Ordovician mud-mounds in the Boda Limestone, Siljan area, central Sweden, consist mainly of massive spiculitic stromatactis limestone similar to other well-known Paleozoic mud-mounds. The mound cores are predominantly formed by spiculite and ostracod-rich mudstone and/or wackestone, and networks of spar-filled syndepositional cavities. The mou...
Article
In 1908, Carl Wiman of Uppsala University, Sweden, discovered rich horizons with Triassic vertebrate remains in Spitsbergen on Svalbard, Norway. This marked the beginning of vertebrate palaeontology as a science in Sweden, subsequently developed mainly through the collection and study of non-Swedish fossil remains. Wiman's accomplishments, resolute...