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1.	Atkins, Christian J., et al. (author) Yochelcionella (Mollusca, Helcionelloida) from the lower Cambrian of North America 2008 In: Bulletin of Geosciences. - : Czech Geological Survey. - 1214-1119 .- 1802-8225. ; 83:1, s. 23-38 Journal article (peer-reviewed)abstract Five named species of the helcionelloid mollusc genus Yochelcionella Runnegar & Pojeta, 1974 are recognized from the lower Cambrian (Cambrian Series 2) of North America: Yochelcionella erecta (Walcott, 1891), Y. americana Runnegar & Pojeta, 1980, Y. chinensis Pei, 1985, Y. greenlandica Atkins & Peel, 2004 and Y. gracilis Atkins & Peel, 2004, linking lower Cambrian outcrops along the present north-eastern seaboard. Yochelcionella erecta, an Avalonian species, is described for the first time, other species are derived from Laurentia. A revised concept of the Chinese species, Y. chinensis, is based mainly on a large sample from the Forteau Formation of western Newfoundland and the species may have stratigraphic utility between Cambrian palaeocontinents.
2.	Dahlqvist, Peter, et al. (author) Late Ordovician shelly faunas from Jamtland: palaeocommunity development along the margin of the Swedish Caledonides 2010 In: Bulletin of Geosciences. - : Czech Geological Survey. - 1214-1119 .- 1802-8225. ; 85:3, s. 505-512 Journal article (peer-reviewed)abstract Late Ordovician shelly faunas occur at several localities in the Ostersund area of Jamtland (Sweden) and developed against a background of intense and rapid global climate change. In the eastern part, approximately in the middle parts of the Krykas Quartzite, and in the western part in the uppermost Kogsta Siltstone changes in faunas and sedimentary patterns provide regional evidence of these global events. In both areas the faunas occur in shale and siltstone facies and are used to effect correlations between the eastern and western parts of the region, which show major differences in facies development. These sub-basins, situated on the margins of a developing mountain belt, reacted differently to global signals providing further evidence of the heterogeneous responses to climate change at the end of the Ordovician Period.
3.	Ebbestad, Jan Ove R., 1967-, et al. (author) Late Ordovician rostroconchs (Mollusca) from fluvial erratics in northwestern Europe 2017 In: Bulletin of Geosciences. - : Czech Geological Survey. - 1214-1119 .- 1802-8225. ; 92:4, s. 405-438 Journal article (peer-reviewed)abstract This paper describes 3 species of ribeirioid and 2 species of conocardiid rostroconchs from fluvially transported erratics in the Dutch-German border area. The material probably stems from Ordovician deposits of the North Estonian Confacies Belt. The ribeirioid specimens from the flaljala group of erratics (Sandhian 2) are represented by Tolmachovia subliratu sp. nov., Beukeria plicata gen. nov. sp. nov. and Ischyrinia viator sp. nov. The single specimen of Tohnachovia is hitherto the youngest occurrence of this genus and the first in Baltica. The presence of subordinate radial ornamentation is added to the emended diagnosis of the genus. The new genus Beukeria is an ischyriniid rostroconch with an elongated conch, two thick pegmas and a plicate shell posterior to vertical axis. Ischyrinia viator is similar to the coeval. I. notTegica Soot-Ryon, 1960 but this has a ventrolateral sinus that is subparallel to the dorsal axis. Conocardild specimens from the Pirgu Ojlemyr chert (Katian 4) are represented by Bitrigonocardia lindstroemi (Isberg) and Pojetaconcha costulata sp. nov. The identification of Bitrigonocardia lindstroemi is circumstantial as the type specimens are missing, but as understood here new details of morphology and ornamentation are given. Pojetaconcha is for the first time recognized outside Laurentia and Australia. Pojetaconcha costulata sp. nov. is distinguished by 14 or 15 broad and flat-topped radial ribs on the body and snout and compares closely with the Chazyan P. alabamensis (Pojeta & Runnegar, 1976), USA. Ischyriniids occur mainly in Baltica with Ischyrinia migrating into Laurentia. A general exchange of Bitrigonocardia and Pojetaconcha is seen between Laurentia and Baltica.
4.	Geyer, Gerd, et al. (author) A remarkable Amgan (Middle Cambrian, Stage 5) fauna from the Sauk Tanga, Madygen region, Kyrgyzstan 2014 In: Bulletin of Geosciences. - : Czech Geological Survey. - 1214-1119 .- 1802-8225. ; 89:2, s. 375-400 Journal article (peer-reviewed)abstract Early Middle Cambrian bituminous coquinoid limestones from a tectonically isolated outcrop in southwestern Kyrgyzstan yield a remarkably diverse fauna, with stem-group cnidarians, trilobites, rhynchonelliformean brachiopods, and other shelly fossils. The fossil site is in the northern foothills of the Turkestan Range and thus forms part of the westernmost extension of the South Tien Shan. The fauna includes two fairly well known trilobite species, Glabrella ventrosa Lermontova, 1940 and Dorypyge richthofeniformis Lermontova, 1940, that provide confident support for an Amgan age of the rocks. New described taxa include the stem-group cnidarian Cambroctoconus kyrgyzstanicus Peel sp. nov., the trilobite Olenoides sagittatus Geyer sp. nov., and the helcionelloid Manasoconus bifrons Peel gen. et sp. nov. Additional fossils within the samples include the trilobites Olenoides sp. A, Kootenia sp., and Pseudoeteraspis? sp.; the rhynchonelliform brachiopods Narynella cf. ferganensis (Andreeva, 1962), Narynella? sp., Austrohedra? sp. nov., and two species of uncertain generic affinity; the tommotiid Tesella sp.; the hyolithelminth Hyolithellus sp.; and the palaeoscolecid Hadimopanella oezgueli Gedik, 1977. Of particular interest is Cambroctoconus kyrgyzstanicus with an octagonal corallum and a sparsely septate calyx.
5.	Geyer, Gerd, et al. (author) The Henson Gletscher Formation, North Greenland, and its bearing on the global Cambrian Series 2-Series 3 boundary 2011 In: Bulletin of Geosciences. - : Czech Geological Survey. - 1214-1119 .- 1802-8225. ; 86:3, s. 465-534 Journal article (peer-reviewed)abstract The Henson Gletscher Formation of North Greenland yields moderately diverse trilobite faunas which bracket the Cambrian Series 2-Series 3 boundary interval. A number of the trilobite taxa permit correlation into other parts of Laurentia and to other Cambrian continents, thus enhancing correlation within this stratigraphical interval of the traditional Lower-Middle Cambrian boundary. In particular, the occurrence of Ovatoryctocara granulata and O. yaxiensis substantially improves the intercontinental recognition of the O. granulata level, a prime GSSP candidate. In contrast, the level with Oryctocephalus indicus cannot be located in a number of Cambrian continents with sufficient precision, making this level unsuitable for the definition of a GSSP for the base of the Cambrian Series 3 and Stage 5. Further support for the correlation potential of the base of the range of Ovatoryctocara granulata comes from recent carbon isotope studies that indicate a striking negative excursion in sections of South China (ROECE event) that probably coincides with similar excursions in Laurentia. Four new trilobite species are described: Zacanthopsis blakeri sp. nov., Protoryctocephalus arcticus sp. nov., Eoptychoparia pearylandica sp. nov. and Onchocephalus? freucheni sp. nov.
6.	Hansen, Jesper, et al. (author) Diversity fluctuations and biogeography of Ordovician brachiopod faunas in northeastern Spitsbergen 2010 In: Bulletin of Geosciences. - : Czech Geological Survey. - 1214-1119 .- 1802-8225. ; 85:3, s. 497-504 Journal article (peer-reviewed)abstract Investigations of Lower and Middle Ordovician brachiopods in northeastern Spitsbergen have revealed strong ties to faunas in North America and Greenland at the generic level, although the fauna appears mostly endemic at the species level. During the early Palaeozoic, the archipelago of Svalbard, including Spitsbergen, was located at equatorial latitudes along the northeastern margin of Laurentia. The northeastern part of Spitsbergen experienced significant sea level changes, changing from very shallow water in the Tremadocian to deep water in the Floian and slowly back to shallow- water carbonate environments in the Middle Ordovician. The Tremadocian and early Floian brachiopod fauna was of low diversity with a high proportion of cosmopolitan warm-water related rhynchonelliform genera. In the late Floian there was an abrupt diversification event, taking place against the background of the increasing isolation of Laurentia, leading to a diverse, mostly endemic fauna. This diverse fauna remained into the Middle Ordovician. A similar diversification event has been recorded in North America, but here it occurs later, in the Dapingian. The diachroneity of brachiopod diversification within different parts of a continent has previously been shown for South China, suggesting that it may be a common phenomenon. In contrast to the mostly endemic Middle Ordovician rhynchonelliform genera, the linguliform brachiopods included many genera with a wide distribution. This difference is attributed to their different dispersal strategies.
7.	Jensen, Soren, et al. (author) Scratch circles from the Ediacaran and Cambrian of Arctic Norway and southern Africa, with a review of scratch circle occurrences 2018 In: Bulletin of Geosciences. - : CZECH GEOLOGICAL SURVEY. - 1214-1119 .- 1802-8225. ; 93:3, s. 287-304 Research review (peer-reviewed)abstract 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 Stahpogieddi Formation, Digermulen Peninsula, Arctic Norway, and from the Ediacaran Nudaus and Urusis formations, Nama Group, of southern Africa. A literature survey confirms a previously noted concentration of scratch circles reported from shallow marine upper Ediacaran-lower Cambrian and paralic Carboniferous rocks. Scratch circle identification and nomenclature are discussed. The stratigraphical range of the trace fossils Treptichnus pedum and Gyrolithes isp. in the Stahpogieddi Formation are extended downward. Combined with earlier reports of Harlaniella podolica this adds new precision to the placement of the Ediacaran-Cambrian boundary on the Digermulen Peninsula.
8.	Lerosey-Aubril, Rudy, et al. (author) Arthropod appendages from the Weeks Formation Konservat-Lagerstatte: new occurences of anomalocaridids in the Cambrian of Utah, USA 2014 In: Bulletin of Geosciences. - : Czech Geological Survey. - 1214-1119 .- 1802-8225. ; 89:2, s. 269-282 Journal article (peer-reviewed)abstract The Guzhangian Weeks Formation (house Range, Utah, USA) contains a virtually unstudied but diverse assemblage of "soft-bodied" organisms. This fauna includes several enigmatic appendages of arthropods that are described in this contribution. Six appendages (two isolated and four paired appendages) are interpreted as frontal appendages of a probably new species of Anomalocaris. They are characterized by a slender morphology, 14 podomeres, ventral spines alternating in size, up to three auxiliary spines per ventral spine, and only two dorsal spines. Another isolated appendage is also tentatively assigned to Anomalocaris, but it exhibits a more robust morphology, a stronger distal tapering, and apparently simple ventral spines, suggesting that it may represent a distinct taxon. These frontal appendages represent the youngest occurrence of anomalocaridids in Laurentia and demonstrate the persistence of older, Burgess Shale-type taxa in the Weeks Formation. An assemblage of four antenniform and six robust and heavily-armed appendages is also described. These are interpreted as the serially arranged, anterior appendages of a single individual of an undetermined arthropod species. This association of three pairs of robust, spiny appendages with two pairs of antenniform structures in a Cambrian arthropod is unique.
9.	Lindström, Anna, et al. (author) Shell repair and shell form in Jurassic pleurotomarioid gastropods from England 2010 In: Bulletin of Geosciences. - : Czech Geological Survey. - 1214-1119 .- 1802-8225. ; 85:4, s. 541-550 Journal article (peer-reviewed)abstract Specimens of the vetigastropods Pleurotomaria Defrance, 1826 and Pyrgotrochus Fischer, 1885, from the Jurassic of England were separated into three morphological groups and surveyed for traces of shell repair. Two measures of shell repair frequencies were calculated: 1) ratio of the number of specimens with at least one repaired injury to the total number of specimens; 2) ratio of the total number of injuries to the total number of specimens in the sample. The Pleurotomaria anglica (Sowerby, 1818) group containing large, high spired trochiform shells showed the lowest repair frequency with 28.8% and 75.3%, respectively. The shell repair frequency in the low spired trochiform Pleurotomaria actinomphala Deslongchamps, 1848 group was 44.4% and 81.0%, respectively. Lastly, the Pyrgotrochus group containing conoidal trochiform shells showed the highest frequency calculated by both methods, 46.2% and 92.3%. Three types of injuries were found in all morphological groups, although in different proportions. Breaks across the entire whorl constitute the majority of repaired injuries in shells of the Pleurotomaria anglica group; in the P. actinomphala group the figure is about 50% and in Pyrgotrochus only 35%. The coniodal shell form and a deep slit in the aperture margin probably proved to be a defensive strategy for Pyrgotrochus, with many fractures terminating at the margin of the slit, whereas Pleurotomaria anglica was protected by its size.
10.	Niedzwiedzki, Grzegorz, 1980-, et al. (author) Middle Devonian invertebrate trace fossils from the marginal marine carbonates of the Zachełmie tetrapod tracksite, Holy Cross Mountains, Poland 2014 In: Bulletin of Geosciences. - : Czech Geological Survey. - 1214-1119 .- 1802-8225. ; 89:3, s. 593-606 Journal article (peer-reviewed)abstract The dolomitic deposits of the Middle Devonian Wojciechowice Formation exposed at the tetrapod tracksite in the Zachełmie Quarry in the Holy Cross Mountains (Poland) are characterised by a low diversity of invertebrate trace fossilassociation. Four ichnoassemblages can be identified in the track-bearing, lower part of the succession. The most conspicuous are trace fossils produced by arthropods (probably crustaceans), which can form distinctive and large horizontal burrows. The described ichnotaxa (cf. Skolithos isp., cf. Balanoglossites isp., Alcyonidiopsis isp., Spongeliomorpha isp., Gordia isp., and Rhizocorallium isp.) are well known from typical marginal-marine and shallow-marine deposits. Nevertheless, the studied assemblages were found in sparsely distributed horizons and are dominated by a single or a few ichnotaxa with locally high trace-densities. Distribution and composition of the trace fossil assemblages probably reflects occurrence of the impoverished, stressed Cruziana ichnofacies. It was affected by changes in water depth with intermittent periods of subaerial exposure connected with salinity fluctuations. The invertebrate trace fossil assemblage, tetrapod tracks and associated sedimentological features point to deposition in a marginal-marine, mostly peritidal and lagoonal environment with minor terrestrial influences.
11.	Peel, John Stuart, et al. (author) A new arthropod from the lower Cambrian Sirius Passet Fossil-Lagerstätte of North Greenland 2009 In: Bulletin of Geosciences. - : Czech Geological Survey. - 1214-1119 .- 1802-8225. ; 84:4, s. 625-630 Journal article (peer-reviewed)abstract Aaveqaspis inesoni gen. et sp. nov., is described from the lower Cambrian Sirius Passet Fossil-Lagerstatte of Peary Land, North Greenland. It has a semicircular head shield and a thorax with 5 tergites. The tail shield carries 2 pairs of spines, the most anterior of which is enormous and dominates the trunk. A. inesoni lacks any preserved trace of eyes, as is also the case with several other Sirius Passet arthropods, suggesting that the fossils accumulated in deeper water than the contemporaneous Chengjiang Fossil-Lagerstatte of China or the middle Cambrian Burgess Shale assemblages of British Columbia.
12.	Peel, John S. (author) A priapulid larva from the middle Cambrian (Wuliuan Stage) of North Greenland (Laurentia) 2022 In: Bulletin of Geosciences. - : Czech Geological Survey. - 1214-1119 .- 1802-8225. ; 97:4, s. 445-452 Journal article (peer-reviewed)abstract A single phosphatised specimen from the middle Cambrian Henson Gletscher Formation (Miaolingian Series, Wuliuan Stage) of North Greenland is interpreted as the hatching larva of a total-group priapulid worm. A plated lorica is not present but probably was developed at a later larval stage, by comparison with the described development of extant Priapulus caudatus and Halicryptus spinulosus. A characteristic priapulid introvert with scalids is not seen but it was likely withdrawn in the available specimen. The new find is consistent with a similar ontogeny in Cambrian priapulid cycloneuralians to that seen in their present day relatives. New taxon: Inuitiphlaskus kouchinskyi gen. et sp. nov.
13.	Peel, John Stuart (author) An epiphytacean-Girvanella (Cyanobacteria) symbiosis from the Cambrian (Series 3; Drumian) of North Greenland (Laurentia) 2018 In: Bulletin of Geosciences. - : CZECH GEOLOGICAL SURVEY. - 1214-1119 .- 1802-8225. ; 93:3, s. 327-336 Journal article (peer-reviewed)abstract The widespread Cambrian calcareous cyanobacterium Girvanella is described in symbiotic association with a new epiphytacean, Orpikania freucheni gen. et sp. nov. (Microproblematica), from the Ekspedition Bra; Formation (Cambrian Series 3, Drumian Stage) of Freuchen Land, North Greenland. The phosphatized assemblages preserve dendrites of the epiphytacean forming a supporting framework for discrete climbing filaments of Girvanella lianifiomis sp. nov. that are firmly attached to their host with holdfasts. Elevation of the slender Girvanella filaments on the framework of the dendrite potentially enhanced their phototactic movement towards the light. Filaments in the co-occurring Girvanella pituutaq sp. nov. are regularly twisted together into a nape-like form which may have assisted elevation above its substrate.
14.	Peel, John S. (author) Articulated hyoliths and other fossils from the Sirius Passet Lagerstätte (early Cambrian) of North Greenland 2010 In: Bulletin of Geosciences. - : Czech Geological Survey. - 1214-1119 .- 1802-8225. ; 85:3, s. 385-394 Journal article (peer-reviewed)abstract Hyolithids with helens and an operculum, and a second species of loricate cycloneuralian, Sirilorica pustulosa sp. nov., are described from the Sirius Passet Lagerstatte (early Cambrian; Cambrian Series 2, Stage 3) of Peary Land, North Greenland. An ethmophylloid archaeocyathan and a species of the bivalved arthropod Isoxys are described in open nomenclature. The association of trace fossils with body fossils is discussed.
15.	Peel, John Stuart (author) Bobellis oliveri gen. et sp. nov. from the Silurian of North Greenland (Laurentia) and the systematic position of pycnomphaline gastropods 2019 In: Bulletin of Geosciences. - : CZECH GEOLOGICAL SURVEY. - 1214-1119 .- 1802-8225. ; 94:2, s. 125-136 Journal article (peer-reviewed)abstract The gastropod Bobellis oliveri gen. et sp. nov. is described from carbonate mounds of the Samuelsen Hoj Formation (early Silurian) within the Washington Land Group of North Greenland (Laurentia). It displays a profound adapertural swing of the growth lines across the upper whorl surface in the multi-whorled trochiform shell; the umbilicus is closed by a prominent funicle. Bobellis oliveri is assigned to the Family Pycnomphalidae (Ordovician-Devonian; nom. transl. Subfamily Pycnomphalinae Peel, 1984) which is transferred to the Euomphaloidea, alongside the morphologically similar Omphalotrochidae (Devonian-Permian). In pycnomphalids the umbilicus is usually partially or completely closed by a prominent circumbilical funicle while the umbilicus of omphalotrochids is generally open.
16.	Peel, John Stuart (author) Molaria (Euarthropoda) from the Sirius Passet Lagerstatte (Cambrian Series 2, Stage 3) of North Greenland 2017 In: Bulletin of Geosciences. - : Czech Geological Survey. - 1214-1119 .- 1802-8225. ; 92:2, s. 133-142 Journal article (peer-reviewed)abstract A second species of the characteristic Burgess Shale euarthropod Molaria Walcott, 1912 is described from the Sirius Passet Lagerstatte of North Greenland, thus extending its range from Cambrian Series 3 (Stage 5) back into Series 2 ( Stage 3). Molaria steini sp. nov. differs from the type species, M. spinifera Walcott, 1912, in having 9 trunk tergites and lacking an elongate connecting segment between the trunk and the jointed telson. Exopod setal fringes are similar to those in the artiopod Emeraldella Walcott, 1912 from the Burgess Shale but other details of limbs remain obscure.
17.	Peel, John Stuart (author) Musculature and shell microstructure of the ancestral bivalve Fordilla (Mollusca) from the lower Cambrian of Greenland (Laurentia) 2023 In: Bulletin of Geosciences. - : Czech Geological Survey. - 1214-1119 .- 1802-8225. ; 98:4, s. 265-287 Journal article (peer-reviewed)abstract Shell microstructure and exquisite details of muscle attachment scars are preserved on the surface of internal moulds in the bivalve Fordilla troyensis from the Aftenstjerneso Formation (Cambrian Series 2, Stage 4) of North Greenland (Laurentia). Subsidiary muscles developed in commarginal series that extend laterally from the anterior and posterior adductor muscles probably controlled the centrally emergent foot. Their position close to the ventral margin indicates that only slight withdrawal and limited manipulation of the foot was possible, confirming that Fordilla was not a burrower. The pattern suggests derivation of Fordilla from a clamping mollusc with shell muscles distributed around the shell margin. No such pattern of serially repeated muscles close to the shell margin is currently known in the few available records of helcionelloid muscle scars, but Postacanthella has a commarginal U-shaped muscle scar reflecting its limpet-shaped shell form. Shell microstructure in Fordilla troyensis is closely similar to Pojetaia, with central areas of the valves dominated by a laterally continuous imbricate lamellar structure with a width of 10-20 mu m between successive crests. Imbricate lamellae with about half this spacing form a marginal zone with crests lying perpendicular to the valve edge. The hinge line lacks teeth, although a single tooth is present in each valve of the related Fordilla sibirica and Fordilla germanica. The site of the simple ligament is coarsely striated. Comparative material of Fordilla troyensis is illustrated from New York State, North-East Greenland and Denmark.
18.	Peel, John S. (author) Ontogeny, morphology and pedicle attachment of stenothecoids from the middle Cambrian of North Greenland (Laurentia) 2021 In: Bulletin of Geosciences. - : Czech Geological Survey. - 1214-1119 .- 1802-8225. ; 96:4, s. 381-399 Journal article (peer-reviewed)abstract The bivalved calcareous shells of stenothecoids are generally both inequilateral and inequivalve. They occur in lower and middle Cambrian strata from Laurentia, Siberia, Kazakhstan and China, but their affinities are unresolved. Contemporary workers favour assignment as a separate class of Mollusca or within the stem-group of Brachiopoda. The latter is supported by the present description of pedicle attachment in stenothecoids from the Henson Gletscher Formation (Miaolingian Series, Wuliuan Stage) of North Greenland. Described material from Greenland is mainly preserved as internal moulds showing a high degree of variability that frustrates comparisons with assemblages from other localities and horizons, but provides insight into central features of stenothecoid morphology. Curvature of individual valves is shown to be an unreliable morphological indicator in the North Greenland sample. Early juveniles of Stenothecoides are described confirming the development of a transverse tooth in the interior of the ventral valve throughout ontogeny. A pitted structure near the apex of juvenile internal moulds is interpreted as the scar of a fibrous pedicle attaching the ventral valve to the substrate. Frondose impressions on the shell interior, previously considered to be characteristic of Bagenovia, are described in Stenothecoides. Multiple median scars on the dorsal valve characteristic of Stenothecella (Cambrian Stage 4) are also described in the Wuliuan material from North Greenland. New species: Stenothecoides terraglaciei sp. nov.
19.	Peel, John Stuart (author) Pseudomyona from the Cambrian of North Greenland (Laurentia) and the early evolution of bivalved molluscs 2021 In: Bulletin of Geosciences. - : CZECH GEOLOGICAL SURVEY. - 1214-1119 .- 1802-8225. ; 96:2, s. 195-215 Journal article (peer-reviewed)abstract The laterally compressed, univalve, Cambrian (Miaolingian Series, Drumian Stage) mollusc Pseudomyona is recorded for the first time from Laurentia. Distinctive internal moulds of the type species Pseudomyona queenslandica, a species otherwise known from Australia and northern Siberia, are described from the Ekspedition Brae Formation of southern Lauge Koch Land, North Greenland. A new species, Pseudomyona groenlandica, characterised by a proliferation of hinge teeth on the supra-apical surface, is described from the overlying Fimbuldal Formation of south-east Freuchen Land. The increase in hinge teeth supports the hypothesis that the bivalved Tuarangia from the Miaolingian Series (Guzhangian Stage) of New Zealand and Bornholm, Denmark, evolved from Pseudomyona. Although bivalved, Tuarangia is not interpreted as Class Bivalvia, but as the most derived member of an early clade in the evolution of Class Rostroconchia. The emended Order Tuarangiida, containing Tuarangia and Pseudomyona, forms a sister group to ribeirioids and later rostroconchs
20.	Peel, John Stuart (author) Teller's operculum : revising a rare operculate gastropod from the Silurian of Wisconsin (Laurentia) 2018 In: Bulletin of Geosciences. - : Czech Geological Survey. - 1214-1119 .- 1802-8225. ; 93:4, s. 499-511 Journal article (peer-reviewed)abstract The unique Silurian gastropod with the operculum in place which Edgar E. Teller in 1910 assigned to Murchisonia conradi Hall is redescribed. The date of authorship of Murchisonia conradi Hall, now transferred to Lophospira Whitfield, and originally described from the Racine Formation of Wisconsin (Laurentia), is established as 1865 and not 1867, 1868 or 1870 as variously claimed. With a focus on the operculum, previous studies of Teller's specimen have neglected the form of the shell itself. Latex casts drawn from the external mould motivate its description as a new species, Lophospira telleri sp. nov., and demonstrate that the operculum was positioned deep within the shell aperture. Although being the only proven lophospiroidean operculum, the paucispiral sinistral (in external view) operculum is typical for dextral gastropods of moderate height in which the parietal wall is well developed and the umbilicus narrow. The development of opercula of this type, and the depth of emplacement of the operculum in L. telleri, may reflect increasing predation pressure on gastropods in the Lower Palaeozoic. Suggestions that the operculum of L. telleri may represent the inner surface of an operculum similar to that in the common Silurian euomphaloidean Oriostoma are rejected. In addition to the original record from Wisconsin, isolated opercula of L. telleri are now reported from Thomton Quarry, Illinois.
21.	Peel, John S., et al. (author) The extent of the Sirius Passet Lagerstatte (early Cambrian) of North Greenland 2011 In: Bulletin of Geosciences. - : Czech Geological Survey. - 1214-1119 .- 1802-8225. ; 86:3, s. 535-543 Journal article (peer-reviewed)abstract Ancillary localities for the Sirius Passet biota (early Cambrian; Cambrian Series 2, Stage 3) are described from the immediate vicinity of the main locality on the southern side of Sirius Passet, north-western Peary Land, central North Greenland, where slope mudstones of the Transitional Buen Formation abut against the margin of the Portfjeld Formation carbonate platform. Whilst this geological relationship may extend over more than 500 km east-west across North Greenland, known exposures of the sediments yielding the lagerst tte are restricted to a 1 km long window at the south-western end of Sirius Passet.
22.	Peel, John S. (author) The oldest palaeoloricate mollusc (Cambrian Series 2, Stage 4; North Greenland) and its bearing on aculiferan evolution 2020 In: Bulletin of Geosciences. - : CZECH GEOLOGICAL SURVEY. - 1214-1119 .- 1802-8225. ; 95:2, s. 127-144 Journal article (peer-reviewed)abstract In the Aculifera Conchifera model of molluscan evolution, spiculate aplacophorans and polyplacophorans with a dorsal series of shell plates are recognised as sister groups within the Glade Aculifera, itself a sister group of the Glade Conchifera that contains all other molluscs. While aculiferans and conchiferans had their common origin near the Precambrian Cambrian boundary, the crown groups of most major molluscan classes are seen traditionally to have emerged in the latest Cambrian (Furongian) Early Ordovician. JI,latthevia Walcott, 1885, from the latest Furongian Early Ordovician of Laurentia, has been regarded almost universally as the oldest undoubted fossil chiton, a palaeoloricate. Palaeoloricates, however, are paraphyletic and Alatthevia is variously interpreted as a time indicator for the origin of crown group Aculifera, within either the stem or crown groups of Aplacophora or Polyplacophora. The discovery of rare disarticulated plates from the early Cambrian (Cambrian Series 2, Stage 4) of North Greenland (Laurentia) extends the geological record of palaeoloricates by about 25 Ma. In bridging the gap between lower stem group aculiferans and the occurrence of Alcuthevia, the new finds offer the potential for a corresponding earlier origin of both aplacophorans and polyplacophorans within the aculiferan crown group. Head and intermediate plates are described from the Aftenstjemeso Formation and placed within a new taxon proposed as Qaleruagia sodermanorum gen. et sp. nov.
23.	Peng, Shanchi, et al. (author) Continuing progress on chronostratigraphic subdivision of the Cambrian System 2011 In: Bulletin of Geosciences. - : Czech Geological Survey. - 1214-1119 .- 1802-8225. ; 86:3, s. 391-396 Journal article (peer-reviewed)abstract This paper is a review of the chief accomplishments toward defining Cambrian stage- and series-level GSSPs since the founding of the International Subcommission on Cambrian Stratigraphy (ISCS) in 1961, and is an assessment of the Subcommission's progress toward defining the bases of remaining provisional stages and series.
24.	Peng, Shanchi, et al. (author) Intraspecific variation and taphonomic alteration in the Cambrian (Furongian) agnostoid Lotagnostus amerkanus: new information from China 2015 In: Bulletin of Geosciences. - : Czech Geological Survey. - 1214-1119 .- 1802-8225. ; 90:2, s. 281-306 Journal article (peer-reviewed)abstract The concept of the agnostoid arthropod species Lotagnostus americanus (Billings, 1860), which has been reported from numerous localities in the upper Furongian Series (Cambrian) of Laurentia, Gondwana, Baltica, Avalonia, and Siberia, is reviewed with emphasis on morphologic and taphonomic information afforded by large collections from Hunan in South China, Xinjiang in Northwest China, and Zhejiang in Southeast China. Comparisons are made with type and topotype material from Quebec, Canada, as well as material from elsewhere in Canada, the USA, the United Kingdom, Sweden, Russia, and Kazakhstan. The new information clarifies the limits of morphologic variability in L. americanus owing to ontogenetic changes and variation within holaspides, including inferred microevolution. It also provides details on apparent variation of taphonomic origin. The Chinese collections demonstrate a moderately wide variation in L. americanus, indicating that arguments favoring restriction of Lotagnostus species to narrowly defined, geographically restricted forms are unwarranted. Species described as L. trisectus (Salter, 1864), L. asiaticus Troedsson, 1937, and L. punctatus Lu, 1964, for example, fall within the range of variation observed in L. americanus, and are regarded as junior synonyms. The effaced form Lotagnosilis obscurus Palmer, 1955 is removed from synonymy with L. americanus. A review of the stratigraphic distribution of L. americanus as construed here shows that the earliest occurrences of the species in all regions of the world are nearly synchronous.
25.	Peng, Shanchi, et al. (author) Rejoinder: Four-series concept of the Cambrian has a long history 2012 In: Bulletin of Geosciences. - : Czech Geological Survey. - 1214-1119 .- 1802-8225. ; 87:3, s. 629-632 Journal article (other academic/artistic)
26.	Popov, Leonid E., et al. (author) Cambrian (Furongian) rhynchonelliform brachiopods from the Eastern Alborz Mountains, Iran 2013 In: Bulletin of Geosciences. - : Czech Geological Survey. - 1214-1119 .- 1802-8225. ; 88:3, s. 525-538 Journal article (peer-reviewed)abstract The Cambrian (Furongian) shallow water carbonates in the Mila Formation in the Tuyeh-Darvar area (eastern Alborz, northern Iran) contain numerous shell beds, entirely composed of disarticulated valves of the billingsellide brachiopods Billingsella? fortis sp. nov. and Hyrcanostrophia tuyehensis gen. et sp. nov. Higher up in the Mila Formation, the shallow water carbonates are replaced by nodular limestones, deposited in an open marine environment, containing Palaeostrophia tecta Nikitin & Popov, 1983 and the early polytoechioid Darvaretoechia prisca gen. et sp. nov. These two different brachiopod assemblages are assigned to the oligotaxic Billingsella and Palaeostrophia associations, respectively. These associations are considered to represent precursors to the brachiopod-dominated benthic assemblages of the Palaeozoic Evolutionary Fauna. The new brachiopod faunas from the Alborz Terrane are closely similar to contemporaneous Furongian faunas from the Australasian sector of Gondwana, in particular, to those from South China and the Kazakhstanian terranes.
27.	Rushton, Adrian A.W, et al. (author) Paradoxidid trilobites from a mid-Cambrian (Series 3, stage 5) limestone concretion from Jämtland, central Sweden 2016 In: Bulletin of Geosciences. - : Czech Geological Survey. - 1214-1119 .- 1802-8225. ; 91:3, s. 515-552 Journal article (peer-reviewed)abstract 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 new: Eccaparadoxides? thorslundi sp. nov. is distinctive, but its generic position is considered doubtful; Hydrocephalus spinulosus is similar to H. vikensis Rushton & Weidner, 2007 (also present as a rarity in the moult ensemble) and is partly distinguished from it by characters of the thorax. Also illustrated are a few specimens that have been collected at various localities between Hackås and Brunflo. They appear to represent individuals of some of the species in the moult ensemble and are about twice the size of their type specimens.
28.	Skovsted, Christian, 1974- (author) A silicified tommotiid from the lower Cambrian of Greenland 2016 In: Bulletin of Geosciences. - : Czech Geological Survey. - 1214-1119 .- 1802-8225. Journal article (peer-reviewed)abstract Three specimens of a new eccentrothecimorph tommotiid are described from the Paralelldal Formation of North Greenland. The specimens are all tubular structures composed of a number of individual sclerites. The sclerites were arranged in rings which fused to form a rigid tube during ontogeny. The tube has a basal aperture presumably allowing attachment to a hard substrate. In morphology, both individual sclerites and the tubular scleritome are remarkably similar to specimens of Eccentrotheca from South Australia. However, the Greenland specimens are silicified and may have been either weakly mineralized or calcareous in original composition. In this respect they differ from all previously known tommotiids, considerably expanding the ultrastructural disparity of the Tommotiida and allowing comparison to a new range of possible lophotrochozoan fossils.
29.	Skovsted, Christian B., et al. (author) Sclerite fusion in the problematic early Cambrian spine-like fossil Stoibostrombus from South Australia 2011 In: Bulletin of Geosciences. - : Czech Geological Survey. - 1214-1119 .- 1802-8225. ; 86:3, s. 651-658 Journal article (peer-reviewed)abstract New collections of the problematic spine like fossil Stoibostrombus crenulatus Conway Morris & Bengtson from the Mt. Scott Range and Wilkawillina Gorge in the central Flinders Ranges, South Australia contain fused sclerite composites. In each fused specimen the spines are merged along their lateral margins and the orientation of the spines is almost identical. These new specimens confirm that Stoibostrombus spines were dermal sclerites, arranged in lateral pairs or transverse rows. The nature of the animal secreting the spines remains elusive, but available evidence suggest that it was an ecdysozoan animal, possibly a palaeoscolecid worm.
30.	Tonarova, Petra, et al. (author) A jawed polychaete fauna from the late Ludlow Kozlowskii event interval in the Prague Basin (Czech Republic) 2012 In: Bulletin of Geosciences. - : Czech Geological Survey. - 1214-1119 .- 1802-8225. ; 87:4, s. 713-732 Journal article (peer-reviewed)abstract This paper deals with a diverse fauna of polychaetes possessing jaws (= scolecodonts) from the late Silurian Kopanina Formation of the Prague Basin (Czech Republic). The most common genera are Kettnerites, Oenonites and Pistoprion; the entire collection contains at least 16 genera. This is in stark contrast to the four genera recorded from this region by previous authors. The fauna described shows great similarities with coeval ones reported from the Baltic area (Gotland and Estonia), Siberia, Arctic Canada and the British Isles. These new data thus extend the palaeobiogeographical and palaeolatitudinal distribution of several taxa, particularly at the genus but also the species level. The sampled interval embraces the Kozlowskii event and its effects on the polychaetes are briefly discussed. Although the collections are relatively small, particularly from post-event strata, a faunal reorganisation is apparent. The studied collection enabled the stratigraphical ranges of some taxa, including tretoprionids and possibly polychaeturids, to be extended into the late Ludlow. One new species, "Mochtyella" pragensis, is described.

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