uu.seUppsala University Publications
Change search
Refine search result
1 - 31 of 31
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 1.
    Agić, Heda
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Moczydłowska, Małgorzata
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Yin, Leiming
    Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences.
    Affnity, life cycle, and intracellular complexity of organic-walled microfossils from the Mesoproterozoic of Shanxi, China2015In: Journal of Paleontology, ISSN 0022-3360, E-ISSN 1937-2337, Vol. 89, no 1, p. 28-50Article in journal (Refereed)
    Abstract [en]

    Light microscope and scanning electron microscope observations on new material of unicellularmicrofossils Dictyosphaera macroreticulata and Shuiyousphaeridium macroreticulatum, from the MesoproterozoicRuyang Group in China, provide insights into the microorganisms’ biological affinity, life cycle and cellularcomplexity. Gigantosphaeridium fibratum n. gen. et sp., is described and is one of the largest Mesoproterozoicmicrofossils recorded. Phenotypic characters of vesicle ornamentation and excystment structures, properties ofresistance and cell wall structure in Dictyosphaera and Shuiyousphaeridium are all diagnostic of microalgalcysts. The wide size ranges of the various morphotypes indicate growth phases compatible with the development ofreproductive cysts. Conspecific biologically, each morphotype represents an asexual (resting cyst) or sexual (zygotic cyst)stage in the life cycle, respectively. We reconstruct this hypothetical life cycle and infer that the organism demonstrates areproductive strategy of alternation of heteromorphic generations. Similarly in Gigantosphaeridium, a metabolicallyexpensive vesicle with processes suggests its protective role as a zygotic cyst. In combination with all these charactersand from the resemblance to extant green algae, we propose the placement of these ancient microorganisms in the stemgroup of Chloroplastida (Viridiplantae). A cell wall composed of primary and secondary layers in Dictyosphaera andShuiyouisphaeridium required a high cellular complexity for their synthesis and the presence of an endomembranesystem and the Golgi apparatus. The plastid was also present, accepting the organism was photosynthetic. The biotareveals a high degree of morphological and cell structural complexity, and provides an insight into ongoing eukaryoticevolution and the development of complex life cycles with sexual reproduction by 1200Ma.

  • 2. Bassett, M.G.
    et al.
    Popov, L.E.
    Holmer, L.E.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    The oldest-known metazoan parasite?2004In: Journal of Paleontology, ISSN 0022-3360, E-ISSN 1937-2337, Vol. 78, no 6, p. 1214-1216Article in journal (Refereed)
  • 3.
    Blazcjowski, Blazcj
    et al.
    Polish Acad Sci, Inst Paleobiol, Twarda 51-55, PL-00818 Warsaw, Poland..
    Niedzwiedzki, Grzegorz
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology.
    Boukhalfa, Kamel
    Univ Gabes, Fac Sci, City Riadh Zerig 6029, Gabes, Tunisia..
    Soussi, Mohamed
    Univ Tunis El Manar, Dept Geol, Fac Sci, Tunis 2092, Tunisia..
    Limulitella tejraensis, a new species of limulid (Chelicerata, Xiphosura) from the Middle Triassic of southern Tunisia (Saharan Platform)2017In: Journal of Paleontology, ISSN 0022-3360, E-ISSN 1937-2337, Vol. 91, no 5, p. 960-967Article in journal (Refereed)
    Abstract [en]

    Numerous well-preserved remains of a new limulid species from the Anisian-lower Ladinian (Middle Triassic) of the Tejra section of southern Tunisia are described. Comparisons are made with limulids from the Triassic deposits of Europe and Australia. The new specimens are congeneric with the type species of Limulitella, but show some morphological differences. Here we describe Limulitella tejraensis new species, a small limulid with semicircular prosoma, small and triangular opisthosoma, well-defined axial ridge, and pleurae along both ridges of the opisthosoma. The Tunisian Limulitella fossils are associated with conchostracans, bivalves, gastropods, and microconchids. Sedimentological and paleontological data from the Tejra section suggest freshwater to brackish-water conditions during the formation of the fossil-bearing interval and the influence of marine transgression into a playa-like environment. Supposed adaptation to the stressful environment sheds new light on the origin and survival of the extant limulines. This is the first report of limulid body fossils from the Triassic of North Africa and the first documentation of Limulitella in the Middle Triassic of northern Gondwanaland.

  • 4.
    Butler, Aodhán D.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Streng, Michael
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Holmer, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Babcock, Loren
    Lund.
    Exceptionally-preserved Mickwitzia from the Indian Springs Lagerstätte.In: Journal of Paleontology, ISSN 0022-3360, E-ISSN 1937-2337Article in journal (Other academic)
    Abstract [en]

    A new assemblage of the early Cambrian stem group brachiopod Mickwitzia is described from the Indian Springs Lagerstätte possessing exceptionally preserved mantle setae. Critical analysis of shell structure and mantle setae from these specimens with those from additional sites with variable diagenetic history reveals the extent of taphonomic alteration and further sheds light on the phylogenetic position of the mickwitziids. A morphometric approach to shell outline and growth landmarks within these specimens reveals a clear species level discriminant signal of Nevada Mickwitzia in comparison to M. monlifera from Sweden. Detailed electron micrographs allow revision of the genus diagnosis for Mickwitzia based on presence of inward pointing phosphatic cones and tangential setae bearing tubes. We also conclude the inward pointing cone structures are not consistent with setal bearing structures as previously thought, but rather represent an endopunctae-like structure. A tommotiid-like shell architecture and presence of acrotretid columns in the dorsal juvenile shell of M. cf. occidens further strengthens the proposed close relationship between stem-group brachiopods and tommotiids.

  • 5.
    Butler, Aodhán D.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Streng, Michael
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Holmer, Lars E.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Babcock, Loren E.
    Exceptionally preserved Mickwitzia from the Indian Springs Lagerstätte (Cambrian Stage 3), Nevada2015In: Journal of Paleontology, ISSN 0022-3360, E-ISSN 1937-2337, Vol. 89, no 6, p. 933-955Article in journal (Refereed)
    Abstract [en]

    ABSTRACT Exceptionally preserved specimens of the Cambrian stem-group brachiopod Mickwitzia occidens Walcott, 1908 are described in detail from the Indian Springs LagerstÀtte in Nevada, USA. Shell structure and preserved mantle setae from these specimens reveal a variable diagenetic (taphonomic) history and provide insight into the phylogenetic position of mickwitziids. Morphologic and morphometric comparison to M. monilifera (Linnarsson, 1869) from Sweden and M. muralensis Walcott, 1913 from British Columbia, Canada reveals clear species-level distinctions. Scanning electron microscopic analysis allows revision of the generic diagnosis. The Mickwitzia shell is characterized by the presence of inwardly pointing phosphatic cones and tangential setae-bearing tubes. The inwardly pointing cone structures are not consistent with setal bearing structures as previously thought, but rather represent endopunctae-like structures. Acrotretid-like shell structures and shell-penetrating setae in M. occidens strengthen the previously proposed close relationship between stem-group brachiopods and tommotiids, a group of small shelly fossils.

  • 6.
    Claybourn, Thomas M.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology. Department of Biological Sciences, Macquarie University, Sydney, NSW 2109.
    Jacquet, Sarah M.
    Department of Geological Sciences, University of Missouri, Columbia, USA.
    Skovsted, Christian B.
    Swedish Museum of Natural History, Stockholm, Sweden.
    Topper, Timothy P.
    Shaanxi Key laboratory of Early Life and Environments, State Key Laboratory of Continental Dynamics and Department of Geology, Northwest University, Xi'an 710069, China.
    Holmer, Lars E.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology. Shaanxi Key laboratory of Early Life and Environments, State Key Laboratory of Continental Dynamics and Department of Geology, Northwest University, Xi'an 710069, China.
    Brock, Glenn A.
    Department of Biological Sciences, Macquarie University, Sydney, Australia.
    Mollusks from the upper Shackleton Limestone (Cambrian Series 2), Central Transantarctic Mountains, East Antarctica2019In: Journal of Paleontology, ISSN 0022-3360, E-ISSN 1937-2337, Vol. 93, no 3, p. 437-459Article in journal (Refereed)
    Abstract [en]

    An assemblage of Cambrian Series 2, Stages 3–4, conchiferan mollusks from the Shackleton Limestone, Transantarctic Mountains, East Antarctica, is formally described and illustrated. The fauna includes one bivalve, one macromollusk, and 10 micromollusks, including the first description of the species Xinjispira simplex Zhou and Xiao, 1984 outside North China. The new fauna shows some similarity to previously described micromollusks from lower Cambrian glacial erratics from the Antarctic Peninsula. The fauna, mainly composed of steinkerns, is relatively low diversity, but the presence of diagnostic taxa, including helcionelloid Davidonia rostrata (Zhou and Xiao, 1984), bivalve Pojetaia runnegari Jell, 1980, cambroclavid Cambroclavus absonus Conway Morris in Bengtson et al., 1990, and bradoriid Spinospitella coronata Skovsted et al., 2006, as well as the botsfordiid brachiopod Schizopholis yorkensis (Ushatinskaya and Holmer in Gravestock et al., 2001), in the overlying Holyoake Formation correlates the succession to the Dailyatia odyssei Zone (Cambrian Stages 3–4) in South Australia.

  • 7.
    Daley, Allison C.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Peel, John S.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    A possible anomalocaridid from the Cambrian Sirius Passet lagerstätte, North Greenland2010In: Journal of Paleontology, ISSN 0022-3360, E-ISSN 1937-2337, Vol. 84, no 2, p. 352-355Article in journal (Refereed)
    Abstract [en]

    The Sirius Passet biota of North Greenland is one of the oldest Cambrian lagerstätten, and although it is dominated by non-mineralized arthropods and lobopods, anomalocaridids have never been identified. Based on a single specimen, we herein describe for the first time an appendage with possible anomalocaridid affinities as suggested by an overall gross morphology similar to that of the frontal appendage of Anomalocaris from other localitites. Tamisiocaris borealis n. gen. and n. sp. has an elongated appendage with paired spines along one margin, and differs from the frontal appendage of Anomalocaris in that segment boundaries are absent and ventral spines are relatively long and spineless. These differences may be taphonomic, but the entire surface of the appendage is covered in a fine fabric, making it unlikely that this appendage was originally segmented or sclerotized. The taxon is tentatively placed within Radiodonta, but this systematic placement cannot be confirmed while complete body specimens are lacking.

  • 8. Friedman, Matt
    et al.
    Blom, Henning
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Physiology and Developmental Biology, Evolutionary Organism Biology.
    A new actinopterygian from the Famennian of East Greenland and the interrelationships of Devonian ray-finned fishes2006In: Journal of Paleontology, ISSN 0022-3360, E-ISSN 1937-2337, Vol. 80, no 6, p. 1186-1204Article, review/survey (Refereed)
    Abstract [en]

    A new actinopterygian, Cuneognathus gardineri new genus and species, is described from the Devonian (Famennian) Obrutschew Bjerg Formation of East Greenland on the basis of multiple incomplete specimens. Cuneognathus most closely resembles Limnomis from the Famennian Catskill Formation of Pennsylvania, and, like that taxon, is known exclusively from freshwater deposits. A cladistic analysis with an ingroup of 13 actinopterygians and an outgroup of five sarcopterygians explores the relationships between the new genus and some of its better-known Devonian contemporaries, and recovers the same four topologies regardless of the implementation of limited character ordering. Cheirolepis is resolved as the most basal of well-known Devonian actinopterygians, consistent with a majority of previous studies. A novel sister-group relationship between Howqualepis and Tegeolepis is found in all trees. Disagreement between the most parsimonious cladograms is concentrated in a clade whose members are often informally referred to as 'stegotrachelids.' Cuneognathus and Limnomis are resolved as sister taxa within this large radiation along with the pairings of Moythomasia dugaringa plus M. nitida and Krasnoyarichtkys plus Stegotrachelus. The arrangement of taxa is conserved when the enigmatic Dialipina is added to the analysis, although the reconstructed position of that genus above both Cheirolepis and Osorioichthys seems improbable. Our scheme of relationships suggests that actinopterygians invaded freshwater environments at least four times during the Devonian, while age constraints indicate that many of the cladogenic events between ingroup taxa included in this study occurred during or before the Givetian.

  • 9.
    Geyer, Gerd
    et al.
    Bayer Julius Maximilians Univ Wurzburg, Lehrstuhl Geodynam & Geomat Forsch, Inst Geog & Geol, D-97074 Wurzburg, Germany..
    Peel, John S.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Middle Cambrian trilobites from the Ekspedition Brae Formation of North Greenland, with a reappraisal of the genus Elrathina2017In: Journal of Paleontology, ISSN 0022-3360, E-ISSN 1937-2337, Vol. 91, no 2, p. 265-293Article in journal (Refereed)
    Abstract [en]

    The richly fossiliferous Ekspedition Brae Formation of North Greenland yields a typical oligospecific fossil assemblage with well-preserved trilobites, helcionelloids, and lingulate brachiopods. The trilobites include Itagnostus subhastatus new species, Itagnostus sp. cf. I. gaspensis (Rasetti, 1948), Elrathina aphrodite new species, Elrathina athena new species, Elrathina hera new species, and Elrathia groenlandica new species-a fossil assemblage typical of the Bathyuriscus-Elrathina Zone as known from the Cordilleran regions of Laurentia. Excellent preservation allows a detailed assessment of the prosopon and elucidates aspects of the ontogenetic development of Elrathina and Elrathia. An evaluation of Elrathina includes a redescription of its type species, E. cordillerae (Rominger, 1887), based on the type material, and indicates that most specimens collected from the Burgess Shale and previously dealt with as E. cordillerae represent a new species.

  • 10.
    Holmer, Lars E.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Popov, Leonid
    Bassett, Michael G.
    Ordovician–Silurian Chileida—first post-Cambrian records of an enigmatic group of Brachiopoda2014In: Journal of Paleontology, ISSN 0022-3360, E-ISSN 1937-2337, Vol. 88, no 3, p. 488-496Article in journal (Refereed)
    Abstract [en]

    Brachiopods of the order Chileida have been recorded previously only from rocks of early to mid-Cambrian age (Botomian–Amgaian). They are typified by having a calcareous strophic shell with a delthyrium and colleplax, and these characters are shown to be present in species of the two new genera Tolen and Trifissura, from the Late Ordovician of Kazakhstan and the Silurian of Sweden and Britain, respectively. In specimens of Trifissura, the triangular colleplax is phosphatized secondarily by bacterial activity. It is suggested that the phosphatized colleplax represents an organic pad and that served as the original attachment structure of Trifissura by encrustation. Tolen and Trifissura represent the first post-Cambrian record of chileides from the Ordovician and Silurian; the new family Trifissuridae forms the first phylogenetic link between Cambrian chileides and Carboniferous–Permian isogrammides.

  • 11.
    Holmer, Lars E.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Popov, Leonid E.
    Streng, Michael
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Miller, James F.
    Lower Ordovician (Tremadocian) lingulate brachiopods from the House and Fillmore formations, Ibex Area, western Utah, USA2005In: Journal of Paleontology, ISSN 0022-3360, E-ISSN 1937-2337, Vol. 79, no 5, p. 884-906Article in journal (Refereed)
    Abstract [en]

    Seven genera and eight species of lingulate brachiopods were recovered from the House Limestone and lower Fillmore Formation, Ibex area, Utah, USA. These strata are assigned to the upper Skullrockian Stage and lower Stairsian Stage of the Ibexian Series (Iapetognathus Conodont Zone to Low Diversity Interval) and are correlated with the Tremadocian Series of the Acado–Baltic Faunal Province. The fauna includes two new linguloid species, Spinilingula prisca and Wahwahlingula sevierensis, one new siphonotretoid species, Schizambon obtusus, and two new acrotretoid species, Eurytreta fillmorensis and Ottenbyella ibexiana. The last species is the first record of the genus in North America and suggests a correlation of the basal Fillmore Formation with the Ceratopyge Limestone in Sweden. A Siphonobolus? covered by long hollow spines may be one of the oldest siphonotretides with such ornament. This fauna and those described previously from older Utah strata document the biodiversification of the Cambrian–Ordovician lingulate brachiopods and demonstrate their potential for regional and intercontinental correlation.

  • 12.
    Holmer, Lars E.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology. Northwest Univ Xian, Early Life Inst, Xian, China; Northwest Univ Xian, Dept Geol, State Key Lab Continental Dynam, Xian, China.
    Zhang, Zhifei
    Northwest Univ Xian, Early Life Inst, Xian, China; Northwest Univ Xian, Dept Geol, State Key Lab Continental Dynam, Xian, China.
    Topper, Timothy P.
    Univ Durham, Dept Earth Sci, Palaeoecosyst Grp, Durham, England.
    Popov, Leonid
    Natl Museum Wales, Dept Geol, Cathays Pk, Cardiff, Wales.
    Claybourn, Thomas
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    The attachment strategies of Cambrian kutorginate brachiopods: the curious case of two pedicle openings and their phylogenetic significance2018In: Journal of Paleontology, ISSN 0022-3360, E-ISSN 1937-2337, Vol. 92, no 1, p. 33-39Article in journal (Refereed)
    Abstract [en]

    The kutorginates are commonly the most abundant rhynchonelliform brachiopod found in the early Cambrian; they are also some of the oldest known rhynchonelliforms, first appearing in the Unnamed Series 2 (Atdabanian equivalent) and becoming extinct sometime in Cambrian Series 3 (Amgaian equivalent). Moreover, kutorginates are the first known member of the rhynchonelliforms for which we have a detailed knowledge of their soft-part anatomy, including the lophophore, digestive tract, and pedicle—all exceptionally preserved in Kutorgina chengjiangensis Zhang et al., 2007 from the early Cambrian Chengjiang Lagerstätte of southern China. The stout and annulated pedicle in the original report was described as protruding between the valves; however, newly collected better-preserved material now clearly shows that the pedicle actually protrudes from the apical perforation of Kutorgina chengjiangensis. This type of apical pedicle has also been described from other early Cambrian rhynchonelliforms, including the problematic chileate Longtancunella chengjiangensis (Zhang et al., 2011a). Exceptionally preserved similar pedicles are also known to emerge apically from the Silurian chileate dictyonellid Eichwaldia subtrigonalis Billings, 1858, as well as from the recently described Silurian chileate Trifissura rigida Holmer, Popov, and Bassett, 2014. However, it is clear that the only other exceptionally preserved kutorginate—a silicified Nisusia—was provided with an adult pedicle emerging between the valves from a posterior gap; thus, Nisusia has two pedicle openings. However, the apical foramen may represent the earliest attachment of the larvae, which subsequently became nonfunctional through ontogeny. It is suggested that both types of attachment strategies may have appeared early in the stem lineage of the Rhynchonelliformea.

  • 13.
    Kear, Benjamin P.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Rich, Thomas H.
    Ali, Mohammed A.
    Al-Mufarrih, Yahya
    Matari, Adel H.
    Al-Massary, Abdu M.
    Halawani, Mohammed A.
    First Triassic lungfish from the Arabian Peninsula2010In: Journal of Paleontology, ISSN 0022-3360, E-ISSN 1937-2337, Vol. 34, no 1, p. 137-140Article in journal (Refereed)
    Abstract [en]

    Triassic lungfish (Dipnoi) have been extensively documented from the Gondwanan continental and marine shelf deposits of Africa and Madagascar (Teixeira, 1949; Lehman et al., 1959; Beltan, 1968; Martin, 1979, 1981; Kemp 1996), Australia (Kemp, 1993, 1994, 1997a, 1998), India (Jainet al., 1964; Jain, 1968), and Antarctica (Dziewa, 1980). Numerous records also exist from Laurasian land masses including Europe (Agassiz, 1838; Schultze, 1981), North America (Case, 1921) and central and eastern Asia (Liu and Yeh, 1957; Vorobyeva, 1967; Martin and Ingavat, 1982). By comparison, nothing is known of contemporary lungfish fossils from the Middle East. Thus, the recent recovery of asingle tooth plate representing a new geographic occurrence of the genus Ceratodus Agassiz, 1838 from paralic marine deposits of the Jilh Formation, a latest Anisian to lower Carnian unit that crops out along the eastern margin of the Proterozoic Arabian Shield in central Saudi Arabia, is significant because it provides the stratigraphically oldest record of dipnoans from the Arabian Peninsula.

  • 14.
    Moczydlowska, Malgorzata
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Westall, Frances
    Foucher, Frederic
    Microstructure and Biogeochemistry of the Organically Preserved Ediacaran Metazoan Sabellidites2014In: Journal of Paleontology, ISSN 0022-3360, E-ISSN 1937-2337, Vol. 88, no 2, p. 224-239Article in journal (Refereed)
    Abstract [en]

    Metazoans (multicellular animals) evolved during the Ediacaran Period as shown by the record of their imprints, carbonaceous compressions, trace fossils, and organic bodies and skeletal fossils. Initial evolutionary experiments produced unusual bodies that are poorly understood or conceived of as non-metazoan. It is accepted that sponges, ctenophorans, cnidarians, placozoans, and bilaterians were members of the Ediacaran fauna, many of which have uncertain affinities. The fossil Sabellidites cambriensis Yanishevsky, 1926, derived from the terminal Ediacaran strata, is the earliest known organically preserved animal that belonged to a newly evolving fauna, which replaced the Ediacara-type metazoans. Morphologically simple soft-bodied tubular fossils, such as S. cambriensis, and biomineralized, as contemporaneous Sinotubulites sp., are not easy to recognize phylogenetically because many unrelated organisms developed encasing tubes independently. Therefore, in addition to morphologic information, evidence derived from the microstructure of the organic wall and its biochemistry may be vital to resolving fossil origins and phylogenetic relationships. Here we present morphological, microstructural and biogeochemical studies on S. cambriensis using various microscopic and spectroscopic techniques, which provide new evidence that supports its siboglinid, annelidan affinity. The late Ediacaran age of Sabellidites fossil constrains the minimum age of siboglinids and the timing of the divergence of including them annelids by fossil record and this could be tested using molecular clock estimates. The fine microstructure of the organic tube in Sabellidites is multi-layered and has discrete layers composed of differently orientated and perfectly shaped fibers embedded in an amorphous matrix. The highly ordered and specific pattern of fiber alignment (i.e., the texture of organic matter) is similar to that of representatives of the family Siboglinidae. The biogeochemistry of the organic matter that comprised the tube, which was inferred from its properties, composition, and microstructure, is consistent with chitin and proteins as in siboglinids.

  • 15.
    Moczydlowska-Vidal, Malgorzata
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Life cycle of early Cambrian microalgae from the Skiagia-plexus acritarchs2010In: Journal of Paleontology, ISSN 0022-3360, E-ISSN 1937-2337, Vol. 84, no 2, p. 216-230Article in journal (Refereed)
    Abstract [en]

    Light microscopy studies on new materials and museum collections of early Cambrian organic-walled microfossils, informally called acritarchs, provide the observations on phenetic features that permit a comparison to certain Modern microalgae and the recognition of various developmental stages in their life cycle. The microfossils derive from various depositional settings in Estonia, Australia, Greenland, Sweden and Poland.

    The exceptionally preserved microfossils reveal the internal body within the vesicle, - the endocyst -, and the process of releasing the endocyst from the cyst. Vegetative cells, cysts and endocysts are distinguished, and the hypothetical reconstruction of a complex life cycle with the alternation of sexual and asexual generations is proposed. Acritarchs from the Skiagia-plexus are cysts, and likely zygotes in the sexual generation, which periodically rested as “benthic plankton”. Some microfossils of the Leiosphaeridia-plexus are inferred to be vegetative cells, were planktonic and probably haplobiontic. These form-taxa may belong to a single biological species, or a few closely related species, and represent the developmental stages and alternating generations in a complex life cycle that are expressed by polymorphic, sphaero- and acanthomorphic acritarchs. The morphological resemblance and diagnostic cell walls ultrastructure with the trilaminar sheath structure known from earlier studies suggest that the early Cambrian microfossils are the ancestral representatives and/or early lineages to Modern Class Chlorophyceae, and the orders Volvocales and Chlorococcales.

  • 16. Morris, Simon Conway
    et al.
    Peel, John Stuart
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    A New Helcionelloid Mollusk from the Middle Cambrian Burgess Shale, Canada2013In: Journal of Paleontology, ISSN 0022-3360, E-ISSN 1937-2337, Vol. 87, no 6, p. 1067-1070Article in journal (Refereed)
    Abstract [en]

    Burgess Shale-type faunas provide unique insights into the Cambrian "explosion". Their degree of representativeness of Cambrian marine life in general is, however, less easy to establish. One line of evidence is to consider only the skeletal component of a Burgess Shale-type fauna and compare that with a typical Cambrian assemblage. This paper describes a new species of helcionelloid mollusk (Totoralia reticulata n. sp.) from the middle Cambrian Burgess Shale of British Columbia. Whilst much rarer than the co-occurring smooth shelled helcionelloid Scenella amii, the strongly costate morphology of Totoralia reinforces comparisons with Cambrian shelly faunas. The extension of the range of Totoralia from Argentina to Canada adds support to the proposed derivation of the Precordillera terrane of Mendoza from Laurentia.

  • 17.
    Peel, John S.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    A corset-like fossil from the Cambrian Sirius Passet Lagerstätte of North Greenland and its implications for cycloneuralian evolution2010In: Journal of Paleontology, ISSN 0022-3360, E-ISSN 1937-2337, Vol. 84, no 2, p. 332-340Article in journal (Refereed)
    Abstract [en]

    A large (maximum length 80 mm), tubular, corset-like problematic fossil from the early Cambrian (Cambrian Series 2, Stage 3) Sirius Passet Lagerstate of North Greenland is interpreted as the lorica of an ancestral loriciferan. In addition to the double circlet of 7 plates composing the lorica, Sirilorica carlsbergi new genus, new species also preserves Up to Six multicuspidate Cuticular denticles that are similar in shape to the pharyngeal teeth of priapulid worms, although their location is suggestive of scalids. Whilst traditionally placed as a sister group Of priapulid worms within Vinctiplicata (Scalidophora), recent molecular sequence data Suggest that loriciferans might be more closely related to nematomorphs. The limited morphological information available from Sirilorica is consistent with this interpretation, placing the Sirius Passet fossil within the total-group of Loricifera, within the Loricifera + Nematomorpha clade.

  • 18.
    Peel, John Stuart
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    A problematic cnidarian (Cambroctoconus; Octocorallia?) from the Cambrian (Series 2-3) of Laurentia2017In: Journal of Paleontology, ISSN 0022-3360, E-ISSN 1937-2337, Vol. 91, no 5, p. 871-882Article, review/survey (Refereed)
    Abstract [en]

    The problematic calcified cnidarian Cambroctoconus is described from the Henson Gletscher Formation (Cambrian Series 2, Stage 4-Series 3, Stage 5) of North Greenland, representing the first record from Laurentia of a genus otherwise recently described from China, Kyrgyzstan, and Korea. Internal molds produced by penetrative phosphatization mirror the pervasive pore system of the calice walls and septa. The pore system is compared to the network of gastrodermal solenia that distributes nutrients between polyps and surrounding stolon tissues in present day octocorals. In conjunction with the octagonal form of the individual coralla and eight-fold symmetry of septa, the pore system promotes assignment of Cambroctoconus to the Octocorallia, a basal clade in cnidarian phylogeny. Octocorals ('soft corals') are diverse in present day seas, but have a poor fossil record despite the general development of distinctive calcareous spicules. New taxa: Order Cambroctoconida new; Cambroctoconus koori new species.

  • 19.
    Peel, John Stuart
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Tarimspira from the Cambrian (Series 2, Stage 4) of Laurentia (Greenland): extending the skeletal record of paraconodontid vertebrates2019In: Journal of Paleontology, ISSN 0022-3360, E-ISSN 1937-2337, Vol. 93, no 1, p. 115-125Article in journal (Refereed)
    Abstract [en]

    Phosphatic sclerites of the problematic Tarimspira Yue and Gao, 1992 (Cambrian Series 2) recovered by weak acid maceration of limestones display a unique range of mainly strongly coiled morphologies. They were likely organized into multielement scleritomes, but the nature of these is poorly known; some sclerites may have had a grasping function. Tarimspira sclerites grew by basal accretion in an analogous fashion to younger paraconodonts (Cambrian Series 3-4) but lack a basal cavity. Based on proposed homologies, Tarimspira may provide an extension of the early vertebrate paraconodont-euconodont clade back into the early Cambrian. Tarimspira is described for the first time from Laurentia (North Greenland), extending its known range from China and Siberia in Cambrian Series 2. In addition to the type species, Tarimspira plana Yue and Gao, 1992, the Greenland record of Tarimspira includes two morphotypes of a new species, Tarimspira artemi.

  • 20.
    Peel, John Stuart
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Streng, Michael
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    A new middle Cambrian bradoriid arthropod from Greenland and western Canada2015In: Journal of Paleontology, ISSN 0022-3360, E-ISSN 1937-2337, Vol. 89, no 1, p. 96-102Article in journal (Refereed)
    Abstract [en]

    Circum-Laurentian middle Cambrian (Cambrian Series 3) deposits in Greenland and British Columbia yield a new hipponicharionid bradoriid arthropod, Flumenoglacies n. gen., characterized by a comarginal, ramp-like structure which is crested by a continuous lobe. The narrow lobe is the result of the medial fusion of anterior and posterior lobes, seemingly a recurrent theme in hipponicharionid evolution. The type species, F. groenlandica n. sp., is described from the Ekspedition Brae Formation (Drumian Stage) of Peary Land but the description of two unnamed species from slightly older middle Cambrian strata of the Stephen Formation of British Columbia provides additional evidence for the wide distribution of Small Shelly Faunas during the Cambrian.

  • 21. Popov, Leonid E.
    et al.
    Holmer, L. E.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Gorjansky, V. Ju.
    Late Ordovician and early Silurian Trimerellide brachiopodes from Kazakhstan1997In: Journal of Paleontology, ISSN 0022-3360, E-ISSN 1937-2337, Vol. 71, no 4, p. 584-598Article in journal (Refereed)
  • 22. Popov, Leonid
    et al.
    Holmer, Lars E.
    Palaeobiology. Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Miller, J. F.
    Lingulate brachiopods from the Cambrian-Ordovician boundary beds of Utah2002In: Journal of Paleontology, ISSN 0022-3360, E-ISSN 1937-2337, Vol. 76, no 2, p. 211-228Article in journal (Refereed)
    Abstract [en]

    Seven genera and eight species of lingulate brachiopods are described from the Cambrian-Ordovician boundary beds (Cambrooistodus minutus Conodont Subzone to Rossodus manitouensis Conodont Zone) at the Lawson Cove and Lava Dam North sections, Ibex area, Utah, USA. The fauna includes one new linguloid genus, Wahwahlingula, and four new species, Lingulella? incurvata, Zhanatella utahensis, Conotreta millardensis, and Quadrisonia? lavadamensis. Lingulate brachiopods from this interval are very poorly known from Laurentia, but the recorded fauna is very similar to that described from coeval beds at Malyi Karatau, Kazakhstan, and both areas contain Eurytreta cf. bisecta (Matthew, 1901); E. sublata Popov, 1988; ZhanatellaKoneva, 1986; SchizambonWalcott, 1889; and Wahwahlingula. Eurytreta cf. bisecta is also known from the Lower Ordovician of Avalonian Canada, Britain, and Scandinavia.

  • 23.
    Poropat, Stephen F.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Colin, Jean-Paul
    Reassessment of the Early Cretaceous Non-Marine Ostracod Genera Hourcqia Krömmelbein, 1965 and Pattersoncypris Bate, 1972 with the Description of a New Genus, Kroemmelbeincypri2012In: Journal of Paleontology, ISSN 0022-3360, E-ISSN 1937-2337, Vol. 86, no 4, p. 699-719Article in journal (Refereed)
    Abstract [en]

    The Early Cretaceous non-marine ostracod genera Hourcqia Krömmelbein and Pattersoncypris Bate are reinstated. A previously published referral of Hourcqia to Cypridea Bosquet is rejected due to the absence of an anteroventral rostrum in the holotype of the type species Hourcqia africana Krömmelbein. The genus Hourcqia is characterized by an "inverse" valve ratio (right valve larger than left) and the lack of an anteroventral rostrum, and the diagnosis of the genus is broadened to accommodate ornamented forms, resulting in the acceptance of five species: Hourcqia africana, H. confluens (Krömmelbein and Weber), H. kouilouensis (Grosdidier), H. bateke (Grosdidier) and H. sylvesterbradleyi (Bate). The previously published synonymy of Pattersoncypris with the genus Harbinia Tsao is also rejected. The diagnosis of Pattersoncypris is refined, meaning that three species are recognized: Pattersoncypris micropapillosa Bate, P. salitrensis (Krömmelbein and Weber), and P. sinuata (Krömmelbein and Weber). The new genus Kroemmelbeincypris is erected for two species initially assigned to Hourcqia, and subsequently to Pattersoncypris and Harbinia by different authors: Kroemmelbeincypris symmetrica (Krömmelbein and Weber) and K. angulata (Krömmelbein and Weber). The genus Hourcqia is diagnostic of latest Barremian non-marine settings, whilst Pattersoncypris and Kroemmelbeincypris characterize Aptian saline lacustrine environments. The geographic ranges of all three genera are restricted to northeastern and eastern Brazil and northern and western Africa, though a species of Pattersoncypris (P. dakotaensis Tibert and Colin) is also present in the United States.

  • 24.
    Scholze, Frank
    et al.
    TU Bergakad Freiberg, Geol Inst, Freiberg, Germany; Kazan Fed Univ, Inst Geol & Petr Technol, Kazan, Russia.
    Golubev, Valeriy K.
    Russian Acad Sci, Borissiak Paleontol Inst, Moscow, Russia; Kazan Fed Univ, Inst Geol & Petr Technol, Kazan, Russia.
    Niedzwiedzki, Grzegorz
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology.
    Schneider, Joerg W.
    TU Bergakad Freiberg, Geol Inst, Freiberg, Germany; Kazan Fed Univ, Inst Geol & Petr Technol, Kazan, Russia.
    Sennikov, Andrey G.
    Russian Acad Sci, Borissiak Paleontol Inst, Moscow, Russia; Kazan Fed Univ, Inst Geol & Petr Technol, Kazan, Russia.
    Late Permian conchostracans (Crustacea, Branchiopoda) from continental deposits in the Moscow Syneclise, Russia2019In: Journal of Paleontology, ISSN 0022-3360, E-ISSN 1937-2337, Vol. 93, no 1, p. 72-97Article in journal (Refereed)
    Abstract [en]

    The Moscow Syneclise on the East European Platform is an important area for the study of the continental biota of late Permian to Early Triassic age in continuous sections. This study attempts a taxonomic description of the late Permian conchostracan fauna of this area. The rich, new material was collected, bed by bed, during geological and paleontological excavations of lacustrine and fluvial deposits of the Obnora Formation and Vokhma Formation of the late Permian Zhukovian Regional Stage near the towns of Vyazniki and Gorokhovets. The conchostracan fauna of the Zhukovian Regional Stage consists predominantly of Pseudestheria and less frequently of Palaeolimnadiopsis. In the earliest Triassic Vokhmian Regional Stage, a more diverse fauna including Euestheria, Magniestheria, Cornia, Palaeolimnadiopsis, and Rossolimnadiopsis was already recorded. The preliminary taxonomic determination of the pseudestheriids from the Zhukovian Regional Stage is intended to serve as a prerequisite for future studies of late Permian conchostracan biostratigraphy on the regional to interregional scale.

  • 25. Skovsted, Christian B.
    et al.
    Brock, Glenn A.
    Holmer, Lars E.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Topper, Timothy P.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Larsson, Cecilia M.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    The early Cambrian tommotiid Kulparina rostrata from South Australia2015In: Journal of Paleontology, ISSN 0022-3360, E-ISSN 1937-2337, Vol. 89, no 6, p. 920-932Article in journal (Refereed)
    Abstract [en]

    ABSTRACT The early Cambrian (Terreneuvian, Stage 2) tommotiid Kulparina rostrata Conway Morris and Bengtson in Bengtson et al., 1990 is revised. The pyramidal sclerites of K. rostrata are shown to be bilaterally symmetrical and homologues of the symmetrical S1 sclerites of Paterimitra pyramidalis Laurie, 1986. The scleritome of K. rostrata is also shown to include flattened asymmetrical sclerites that were originally described under the name Eccentrotheca guano Bengtson in Bengtson et al., 1990 and which correspond to the L-sclerites of Paterimitra. A modified tubular scleritome and a sessile filter-feeding mode of life is envisaged for Kulparina rostrata.

  • 26.
    Skovsted, Christian B.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Peel, John S.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Early Cambrian brachiopods and other shelly fossils from the basal Kinzers Formation of Pennsylvania2010In: Journal of Paleontology, ISSN 0022-3360, E-ISSN 1937-2337, Vol. 84, no 4, p. 754-762Article in journal (Refereed)
    Abstract [en]

    An assemblage of seventeen species of Small Shelly Fossils, dominated by the brachiopod Eothele tubulus and species of the mollusk Yochelcionella, is described from the basal Kinzers Formation of Thomasville, Pennsylvania. The occurrence extends southwards the distribution of an Early Cambrian fauna (Cambrian Series 2, Stage 4) that is otherwise characteristic of the eastern shelf of Laurentia from New York to Greenland. The poorly known acrothelid brachiopod Eothele tubulus is redescribed based on large collections of ventral valves. The shell structure of E. tubulus is characterized by orthogonal baculae, and represents the oldest known example of a baculate shell structure, indicating that this type of shell structure evolved already in the Early Cambrian.

  • 27.
    Skovsted, Christian B.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Peel, John S.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Hyolithellus in life position from the Lower Cambrian of North Greenland2011In: Journal of Paleontology, ISSN 0022-3360, E-ISSN 1937-2337, Vol. 85, no 1, p. 37-47Article in journal (Refereed)
    Abstract [en]

    Tubular specimens belonging to Hyolithellus from silty dolostones of the basal Aftenstjernesø Formation of North Greenland may represent the first occurrence of this widespread Cambrian fossil in life position. A high proportion of preserved specimens are oriented normal to bedding with the tapering end of the tube down. Occasional undulations in the growth of the tubes indicate that the animal actively adjusted its growth to achieve a vertical orientation in relation to the sediment surface. Increasing thickness of the tube wall towards the tapering end shifted the center of mass downwards and resulted in greater stability in the sediment. The tube remained open at both ends throughout ontogeny; it was most likely secreted by an annelid-grade animal which pumped water into the sediment through the tube. Hyolithellus and similar tubular fossils from the Lower Cambrian probably represent stem group annelids.

  • 28.
    Streng, Michael
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Emiliania Sánchez, 1999 is not a homonym of Emiliania Hay and Mohler, 19672010In: Journal of Paleontology, ISSN 0022-3360, E-ISSN 1937-2337, Vol. 84, no 6, p. 1226-1226Article in journal (Other academic)
  • 29.
    Streng, Michael
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Mellbin, Barbro B.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology.
    Landing, Ed
    Keppie, J. Duncan
    Linguliform brachiopods from the terminal Cambrian and lowest Ordovician of the Oaxaquia microcontinent (Southern Mexico)2011In: Journal of Paleontology, ISSN 0022-3360, E-ISSN 1937-2337, Vol. 85, no 1, p. 122-155Article in journal (Refereed)
    Abstract [en]

    Eighteen taxa of linguliform brachiopods, mainly represented by acrotretoids, are reported from the Upper Cambrian (Furongian, Stage 10) and Lower Ordovician (Tremadocian) Tinu Formation of Oaxaca State, Mexico. At the time of deposition, this area was part of Oaxaquia, which was either a microcontinent or an integral part of the Gondwanan margin. Whereas certain trilobites seem to indicate a Gondwanan affinity, the Tinu brachiopod faunas show a less definite paleogeographic relationship. Some taxa have previously only been reported from Laurentia (Eurytreta cf. fillmorensis, Eurytreta cf. campaniformis), and one taxon is best known from the Avalon microcontinent (Eurytreta cf. sabrinae). However, the relatively high percentage of new and potentially endemic taxa (Oaxaquiatreta labrifera n. gen. n. sp., Tapuritreta reclinata n. sp., Oaxaquiatreta sp., Eurytreta? n. sp., Acrotretidae n. gen. n. sp., Obolinae gen. and sp. indet.) and the lack of other typical Laurentian, Gondwanan, or Avalonian taxa suggest either a certain degree of insularity of Oaxaquia or reflects a more temperate, unrestricted marine environment during the Early Paleozoic. Other taxa reported from the Tinu Formation include Semitreta sp., Lingulella? spp., Obolinae gen. and sp. indet., Eoscaphelasma? sp., Ottenbyella? sp. A and sp. B, and Acrotretidae gen. and sp. indet. A, B, and C. Eurytreta and Semitreta are critically reviewed and several taxa previously assigned to them have been excluded. An emended diagnosis for the genus Eurytreta is presented. The presence of delthyrium and notothyrium-like structures in the siphonotretid Oaxaquiatreta n. gen. further strengthens the previously proposed relationship between the Siphonotretida and Paterinida.

  • 30.
    Sutton, MD
    et al.
    Department of Earth Sciences, University of Oxford, Parks Road, Oxford, UK.
    Holmer, LE
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Cherns, L
    Department of Earth Sciences, Cardiff University, Wales, UK.
    Small problematic phosphatic sclerites from the Ordovician of Iapetus2001In: Journal of Paleontology, ISSN 0022-3360, E-ISSN 1937-2337, Vol. 75, no 1, p. 1-8Article in journal (Refereed)
    Abstract [en]

    Problematic sclerites are common in Cambrian rocks around the world, but much less so in those of the Ordovician. Eurytholia prattensis new genus and species and E. elibata new species, described herein, are rare but widely distributed faunal elements in

  • 31. Zhang, Zhifei
    et al.
    Holmer, Lars E.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Popov, Leonid
    Shu, Degan
    An obolellate brachiopod with soft-part preservation from the early cambrian chengjiang fauna of China2011In: Journal of Paleontology, ISSN 0022-3360, E-ISSN 1937-2337, Vol. 85, no 3, p. 460-463Article in journal (Refereed)
    Abstract [en]

    The obolellates represent a poorly understood group of the oldest known cosmopolitan calcareous rhynchonelliform brachiopods. They made their first appearance in the early Atdabanian and became extinct at the end of the Middle Cambrian. Consequently, any information concerning the soft anatomy of this ephemeral lineage of brachiopods has great phylogenetic significance. This is the first report on two specimens of an obolellate with fine preservation of soft parts including the pedicle, marginal setae and possible imprints of a spiral lophophore, recovered from the early Cambrian Chengjiang Konservat Lagerstatte of Kunming, southern China. The setae are thin and densely fringed along the shell margin. The stout pedicle is distinctly composed of densely stacked tabular bodies, lacking a central coelomic lumen; it emerges through a possible foramen, and slightly tapers posteriorly with the distal end attached to exoskeletons of other organisms.

1 - 31 of 31
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf