DOCSLIB.ORG

Isoxys Volucris from the Sirius Passet Lagerstätte, North Greenland

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Isoxys Volucris from the Sirius Passet Lagerstätte, North Greenland Sexual dimorphism within the stem-group arthropod Isoxys volucris from the Sirius Passet Lagerstätte, North Greenland Nielsen, Morten Lunde; Rasmussen, Jan Audun; Harper, David A. T. Published in: Bulletin of the Geological Society of Denmark Publication date: 2017 Document version Publisher's PDF, also known as Version of record Document license: Other Citation for published version (APA): Nielsen, M. L., Rasmussen, J. A., & Harper, D. A. T. (2017). Sexual dimorphism within the stem-group arthropod Isoxys volucris from the Sirius Passet Lagerstätte, North Greenland. Bulletin of the Geological Society of Denmark, 65, 47-58. Download date: 08. Apr. 2020 Sexual dimorphism within the stem-group arthropod Isoxys volucris from the Sirius Passet Lagerstätte, North Greenland MORTEN LUNDE NIELSEN, JAN AUDUN RASMUSSEN & DAVID A.T. HARPER Nielsen, M.L., Rasmussen, J.A. & Harper, D.A.T. 2017. Sexual dimorphism within the stem-group arthropod Isoxys volucris from the Sirius Passet Lagerstätte, North Greenland. © 2017 by Bulletin of the Geological Society of Denmark, Vol. 65, pp. 47–58. ISSN 2245-7070. (www.2dgf.dk/publika- tioner/bulletin). Morphometric analyses carried out on 126 specimens of the early Cambrian (Cambrian Series 2, Stage 3) stem-group arthropod Isoxys volucris from North Greenland reveal a bimodal distribution, where Morphogroup A is characterised by a significantly wider doublure than Morphogroup B. The dimor- phism is interpreted as intraspecific variation related to gender (sexual dimorphism), where the relative Received 15 December 2016 numbers of individuals within the two morphogroups are equal (ratio 1:1). The discovery of established Accepted in revised form sexual dimorphism in Isoxys may have implications for the taxonomic discrimination of other stem- 5 May 2017 group arthropods within the morphologically diverse and disparate animals of the early Cambrian. Published online 5 July 2017 Keywords: Sirius Passet Lagerstätte, Isoxys, stem-group arthropods, sexual dimorphism, early Cambrian. Morten Lunde Nielsen [[email protected]], Natural History Museum of Denmark, University of Co- penhagen, Øster Voldgade 5–7, DK-1350 Copenhagen K, Denmark. Jan Audun Rasmussen [jan.rasmussen@ museummors.dk], Fossil and Mo-clay Museum, Museum Mors, Skarrehagevej 8, DK-7900 Nykøbing Mors, Denmark. David A.T. Harper [[email protected]], Department of Earth Sciences, Palaeoecosystems Group, Durham University, Stockton Road, Durham DH1 3LE, United Kingdom; also Department of Geol- ogy, Lund University, Sölvegatan 12, S-223 62 Lund, Sweden. Corresponding author: Jan Audun Rasmussen The arthropod Isoxys volucris Williams, Siveter & Peel 2006; Wang et al. 2010, 2012; Fu et al. 2011, 2014; Schoe- 1996 is the most common fossil in the lower Cambrian nemann & Clarkson 2011; Huang & Wang 2014); France Sirius Passet Lagerstätte of Peary Land, North Green- (Vannier et al. 2005); Greenland (Conway Morris et al. land (Stein et al. 2010; Peel & Ineson 2011b) except for 1987; Williams et al. 1996; Peel 2010; Stein et al. 2010); the trilobite Buenellus higginsi Blaker 1988. The genus Russia (Ivantsov 1990); Spain (Richter & Richter 1927); is a stem-group arthropod (Legg & Vannier 2013) and U.S.A. (Walcott 1890; Campbell & Kauffman 1969; and is enclosed by an elongate, non-mineralised, Briggs et al. 2008). Isoxys volucris is distinguished from bivalved carapace, although it remains unresolved other species of Isoxys by, for example, its long, narrow whether it is dorsally folded or hinged (see e.g. Stein spines and broad, conspicuous, wrinkled doublure. et al. 2010), and with long antero- and postero-dorsal The soft parts of I. volucris are rarely preserved and spines. Isoxys has a widespread distribution which is are known only from a few incomplete specimens latitudinally restricted to the tropical and subtropical (Stein et al. 2010). This makes comparisons with other regions (Williams et al. 1996; Vannier & Chen 2000). species of Isoxys difficult and its affinities uncertain, Representatives of the genus have been reported from and it has even been surmised that I. volucris is not a the lower and middle Cambrian of several countries: true member of the genus (Vannier et al. 2006, p. 211). Australia (Glaessner 1979; Bengtson et al. 1990; García- However, a cladistic analysis by Legg & Vannier (2013) Bellido et al. 2009a); Canada (Walcott 1908; Simonetta & firmly demonstrated that Isoxys volucris belongs to the Delle Cave 1975; Conway Morris 1979; García-Bellido genus Isoxys. Despite having been collected in great et al. 2009b; Vannier et al. 2009; Kimmig & Pratt 2015); numbers, our knowledge of I. volucris is fairly limited, China (e.g. Jiang 1982; Hou 1987; Hou & Bergström partly because only few morphological characters are 1991; Shu et al. 1995; Vannier & Chen 2000; Luo et al. preserved. However, an elongate, medially placed Sexual dimorphism in arthropod Isoxys volucris from Sirius Passet · 47 structure interpreted as a possible body attachment approximately 15°S (Fig. 1). The Buen Formation is (Stein et al. 2010) occurs sporadically in the studied approximately 210–250 m thick at Navarana Fjord material. I. volucris was described in detail first by less than 40 km south-west of Sirius Passet (Higgins Williams et al. (1996) and subsequently by Stein et et al. 1991). The Sirius Passet locality is situated in al. (2010). The genus Isoxys has been interpreted as a westernmost Peary Land at 82°47.6′N, 42°13.7′W (Fig. pelagic hunter or scavenger (Zhao et al. 2014). 1), close to the eastern shores of J.P. Koch Fjord. The Here, we describe morphometric analyses on 126 geological setting of the Sirius Passet fossil locality reasonably well-preserved specimens of I. volucris col- was described in detail by Ineson & Peel (2011) and lected in situ, which allow a test of recently detected only a few points need to be added here. dimorphism in Isoxys based on material from China The section is steeply dipping and exposes ap- (Fu et al. 2014). Furthermore, we examine a number of proximately 12 m of platy, dark grey to black, lami- possible reasons for the observed dimorphism within nated mudstones belonging to the ‘Transitional Buen Isoxys volucris. Formation’ (Fig. 2). The section was excavated during the 2011 expedition to the locality. It contains finely laminated mudstones and interbedded intervals of non-laminated to weakly laminated mudstones with Geological setting weak to moderate degrees of bioturbation; the Lager- stätte is only preserved in the former. Its base and top The fossiliferous beds containing the Sirius Passet is covered by scree and thus not exposed. The locality Lagerstätte are black slates of the Buen Formation, is wedged between the underlying dolostones of the more specifically the so-called ‘Transitional Buen Portfjeld Formation to the east and an intraformational Formation’ of Peary Land, North Greenland (Ineson thrust along the western to northern boundary. The & Peel 2011; Peel & Ineson 2011a, 2011b). It has been majority of the collected fossil material was sampled correlated with Cambrian Series 2, Stage 3 (Peel & in situ at the main section. In addition, fossils of Isoxys Ineson 2011a), and is roughly contemporaneous with volucris have been reported from four other localities the Chinese Chengjiang Biota. In terms of absolute in the ‘Transitional Buen Formation’ in close vicinity dating, the age of the formation is about 520–515 Ma to the main outcrop, although these localities have a (Gradstein et al. 2012). During this time interval North rather poor fossil yield (Peel & Ineson 2011a). The dep- Greenland was situated just south of the Equator at ositional setting of the Sirius Passet Lagerstätte was A 30°N B 60°W 45°W 30°W Ellesmere Arctic Ocean Nansen Island Equator Land J.P. Koch Fjord Navarana Fjord Laurentia Alaska Peary Land 82°N Sirius Passet Lagerstätte Sirius Passet 30°S Lagerstätte 82°N Greenland Siberia Inland Ice Kara Baltica 30°W 60°S 100 km 45°W Fig. 1. A: Palaeogeographic map (at 520 Ma) computed by the BugPlates software (Torsvik & Cocks 2009). Greenland, which is marked in green, was part of the Laurentia continent. B: Present-day locality map showing the Sirius Passet Lagerstätte situated in westernmost Peary Land near J.P. Koch Fjord. 48 · Bulletin of the Geological Society of Denmark previously compared to that of the more renowned stratigraphic interval. More than 250 specimens of Burgess Shale Lagerstätte; both are mudstones depos- Isoxys volucris were evaluated prior to analysis, and ited in relatively deep water adjacent to a carbonate 126 specimens were found suitable for an analysis of platform escarpment (i.e. the Portfjeld Formation) with the doublure. The specimens include both articulated low-energy, poorly oxygenated bottom conditions carapaces and single valves (sensu Stein et al. 2010). All (Ineson & Peel 2011). Periodic interludes of more oxic specimens are housed at the Natural History Museum conditions on the sea bed have been suggested on the of Denmark, University of Copenhagen, Copenhagen, basis of intervals of less laminated and more biotur- Denmark (numbers prefixed by MGUH). bated mudstones. The fauna is generally believed to Because the internal anatomical characters are be parautochthonous but some fossils appear to have very rarely preserved in I. volucris (Stein et al. 2010), been preserved in situ (e.g. Ineson & Peel 2011; Stein et the morphometric analyses have been restricted to al. 2013). The Sirius Passet biota sediments have been characters related to those commonly preserved: total interpreted as being deposited in the upper slope length, total height, doublure width and overall shape coarse-sediment bypass zone (Peel & Ineson 2011b). of the valve (Fig. 3). In a recent study, however, Strang et al. (2016) inter- Specimens were coated with ammonium chloride preted it as a shelf setting, deposited at or just below and photographed using a digital DeltaPix InfinityX the storm wave base, which – based on the occurrence camera connected to a computer, which allowed of cyanobacterial activity – was interpreted as being images to be processed directly by DeltaPix InSight situated in the photic zone.
Load more

Recommended publications
  • The Extent of the Sirius Passet Lagerstätte (Early Cambrian) of North Greenland
    The extent of the Sirius Passet Lagerstätte (early Cambrian) of North Greenland JOHN S. PEEL & JON R. INESON Ancillary localities for the Sirius Passet biota (early Cambrian; Cambrian Series 2, Stage 3) are described from the im- mediate 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 Forma- tion 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 lagerstätte are restricted to a 1 km long window at the south-western end of Sirius Passet. • Keywords: Early Cambrian, Greenland, lagerstätte. PEEL, J.S. & INESON, J.R. The extent of the Sirius Passet Lagerstätte (early Cambrian) of North Greenland. Bulletin of Geosciences 86(3), 535–543 (4 figures). Czech Geological Survey, Prague. ISSN 1214-1119. Manuscript received March 24, 2011; accepted in revised form July 8, 2011; published online July 28, 2011; issued September 30, 2011. John S. Peel, Department of Earth Sciences (Palaeobiology), Uppsala University, Villavägen 16, SE-75 236 Uppsala, Sweden; [email protected] • Jon R. Ineson, Geological Survey of Denmark and Greenland, Øster Voldgade 10, DK-1350 Copenhagen K, Denmark; [email protected] Almost all of the fossils described from the early Cambrian The first fragmentary fossils from the Sirius Passet Sirius Passet Lagerstätte of northern Peary Land, North Lagerstätte (GGU collection 313035) were collected by Greenland, were collected from a single, west-facing talus A.K.
    [Show full text]
  • 1158 Peel.Vp
    A new arthropod from the lower Cambrian Sirius Passet Fossil-Lagerstätte of North Greenland JOHN S. PEEL & MARTIN STEIN Aaveqaspis inesoni gen. et sp. nov., is described from the lower Cambrian Sirius Passet Fossil-Lagerstätte 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-Lagerstätte of China or the middle Cambrian Burgess Shale assemblages of British Columbia. • Key words: Cambrian, arthropod, Sirius Passet, Lagerstätte, Greenland. PEEL,J.S.&STEIN, M. 2009. A new arthropod from the lower Cambrian Sirius Passet Fossil-Lagerstätte of North Greenland. Bulletin of Geosciences 84(4), 625–630 (3 figures). Czech Geological Survey, Prague. ISSN 1214-1119. Manuscript received July 30, 2009; accepted in revised form September 22, 2009; published online October 9, 2009; is- sued December 31, 2009. John S. Peel, Department of Earth Sciences (Palaeobiology), Uppsala University, Villavägen 16, SE-75 236 Uppsala, Sweden; [email protected] • Martin Stein, Museum of Evolution, Uppsala University, Norbyvägen 16, SE-752 36 Uppsala, Sweden; [email protected] Black laminated mudstones and siltstones juxtaposed with biomineralized hard parts is the trilobite Buenellus against the prominent buried escarpment of an eroded Blaker, 1988 which, although restricted to this locality carbonate platform in Peary Land, North Greenland (Blaker & Peel 1997), indicates the Nevadella Zone of the (Fig.
    [Show full text]
  • The Morphology and Evolutionary Significance of the Anomalocaridids
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o my family List of Papers This thesis is based on the following papers, which are referred to in the text by their Roman numerals. I Daley, A.C., Budd, G.E., Caron, J.-B., Edgecombe, G.D. & Collins, D. 2009. The Burgess Shale anomalocaridid Hurdia and its significance for early euarthropod evolution. Science, 323:1597-1600. II Daley, A.C. & Budd, G.E. New anomalocaridid appendages from the Burgess Shale, Canada. In press. Palaeontology. III Daley, A.C., Budd,
    [Show full text]
  • New Palaeoscolecidan Worms from the Lower Cambrian: Sirius Passet, Latham Shale and Kinzers Shale
    New palaeoscolecidan worms from the Lower Cambrian: Sirius Passet, Latham Shale and Kinzers Shale SIMON CONWAY MORRIS and JOHN S. PEEL Conway Morris, S. and Peel, J.S. 2010. New palaeoscolecidan worms from the Lower Cambrian: Sirius Passet, Latham Shale and Kinzers Shale. Acta Palaeontologica Polonica 55 (1): 141–156. Palaeoscolecidan worms are an important component of many Lower Palaeozoic marine assemblages, with notable oc− currences in a number of Burgess Shale−type Fossil−Lagerstätten. In addition to material from the lower Cambrian Kinzers Formation and Latham Shale, we also describe two new palaeoscolecidan taxa from the lower Cambrian Sirius Passet Fossil−Lagerstätte of North Greenland: Chalazoscolex pharkus gen. et sp. nov and Xystoscolex boreogyrus gen. et sp. nov. These palaeoscolecidans appear to be the oldest known (Cambrian Series 2, Stage 3) soft−bodied examples, being somewhat older than the diverse assemblages from the Chengjiang Fossil−Lagerstätte of China. In the Sirius Passet taxa the body is composed of a spinose introvert (or proboscis), trunk with ornamentation that includes regions bearing cuticu− lar ridges and sclerites, and a caudal zone with prominent circles of sclerites. The taxa are evidently quite closely related; generic differentiation is based on degree of trunk ornamentation, details of introvert structure and nature of the caudal re− gion. The worms were probably infaunal or semi−epifaunal; gut contents suggest that at least X. boreogyrus may have preyed on the arthropod Isoxys. Comparison with other palaeoscolecidans is relatively straightforward in terms of compa− rable examples in other Burgess Shale−type occurrences, but is much more tenuous with respect to the important record of isolated sclerites.
    [Show full text]
  • A Problematical Trilobite from the Lower Cambrian of Freuchen Land, Central North Greenland
    A problematical trilobite from the Lower Cambrian of Freuchen Land, central North Greenland Philip D. Lane and Adrian W. A. Rushton A single specimen of a remarkable trilobite is described from the Early Cambrian Buen Formation of north-east Freuchen Land, central North Greenland. It is re­ ferred with doubt to Alacephalus Repina, 1960, as a new species A? davisi sp. nov. It possibly lacked eyes, which makes it one of, if not the, earliest non-agnostoid trilobite with this adaptation. Its thoracic segments have a unique morphology. In some respects the morphology resembles that of various trilobites adapted to low-energy benthic environments of low oxygenation; such trilobites tend to be widely distrib­ uted, and in agreement with this Alacephalus appears to be interprovincial. P. D. L., Department ofGeology, Vniversity ofKeele, Keele, Staffordshire ST5 5BG, V.K. A. W. A. R., British Geological Survey, Keyworth, Nottingham NG12 5GG, U.K. The trilobite described below was collected by Neil C. olenellid trilobite Buenellus higginsi Blaker, 1988 (Fam- ~ Davis from laminated, locally bioturbated, mudstones ily Nevadiidae) is associated with an abundant soft- in north-east Freuchen Land (Fig. l; Geological Survey bodied fauna (Conway Morris et al.. 1987; Conway of Greenland collection 319544) which are estimated to Morris & Peel, 1990; Peel, 1990), together with large be not more than 5 m from the top of the Buen Forma­ articulated sponges such as the demosponge Choia hin­ tion. This formation has been interpreted as a silic­ dei Rigby, 1986; the same kinds of sponges are associ­ ic1astic shelf deposit forming part of the sequence on the ated with the new trilobite in GGU collection 319544.
    [Show full text]
  • Annual Meeting 2011
    The Palaeontological Association 55th Annual Meeting 17th–20th December 2011 Plymouth University PROGRAMME and ABSTRACTS Palaeontological Association 2 ANNUAL MEETING ANNUAL MEETING Palaeontological Association 1 The Palaeontological Association 55th Annual Meeting 17th–20th December 2011 School of Geography, Earth and Environmental Sciences, Plymouth University The programme and abstracts for the 55th Annual Meeting of the Palaeontological Association are outlined after the following summary of the meeting. Venue The meeting will take place on the campus of Plymouth University. Directions to the University and a campus map can be found at <http://www.plymouth.ac.uk/location>. The opening symposium and the main oral sessions will be held in the Sherwell Centre, located on North Hill, on the east side of campus. Accommodation Delegates need to make their own arrangements for accommodation. Plymouth has a large number of hotels, guesthouses and hostels at a variety of prices, most of which are within ~1km of the University campus (hotels with PL1 or PL4 postcodes are closest). More information on these can be found through the usual channels, and a useful starting point is the website <http://www.visitplymouth.co.uk/site/where-to-stay>. In addition, we have organised discount rates at the Jury’s Inn, Exeter Street, which is located ~500m from the conference venue. A maximum of 100 rooms have been reserved, and will be allocated on a first-come-first-served basis. Further information can be found on the Association’s website. Travel Transport into Plymouth can be achieved via a variety of means. Travel by train from London Paddington to Plymouth takes between three and four hours depending on the time of day and the number of stops.
    [Show full text]
  • The Sirius Passet Lagerstätte of North Greenland a Remote Window on the Cambrian Explosion Harper, David A
    The Sirius Passet Lagerstätte of North Greenland a remote window on the Cambrian Explosion Harper, David A. T.; Hammarlund, Emma U.; Topper, Timothy P.; Nielsen, Arne T.; Rasmussen, Jan A.; Park, Tae-Yoon S.; Smith, M. Paul Published in: Journal of the Geological Society DOI: 10.1144/jgs2019-043 Publication date: 2019 Document version Publisher's PDF, also known as Version of record Document license: CC BY Citation for published version (APA): Harper, D. A. T., Hammarlund, E. U., Topper, T. P., Nielsen, A. T., Rasmussen, J. A., Park, T-Y. S., & Smith, M. P. (2019). The Sirius Passet Lagerstätte of North Greenland: a remote window on the Cambrian Explosion. Journal of the Geological Society, 176(6), 1023-1037. https://doi.org/10.1144/jgs2019-043 Download date: 30. Sep. 2021 Review Focus article Journal of the Geological Society Published online July 26, 2019 https://doi.org/10.1144/jgs2019-043 | Vol. 176 | 2019 | pp. 1023–1037 The Sirius Passet Lagerstätte of North Greenland: a remote window on the Cambrian Explosion David A. T. Harper1,2*, Emma U. Hammarlund2,3, Timothy P. Topper4,5, Arne T. Nielsen6, Jan A. Rasmussen7, Tae-Yoon S. Park8 & M. Paul Smith9 1 Palaeoecosystems Group, Department of Earth Sciences, Durham University, Durham DH1 3LE, UK 2 Department of Geology, University of Lund, Sölvegatan 12, SE 223 62 Lund, Sweden 3 Department of Laboratory Medicine, Translational Cancer Research, Lund University, Scheelevägen 2, Medicon Village 404, SE-223 81 Lund, Sweden 4 Shaanxi Key Laboratory of Early Life and Environments, State
    [Show full text]
  • Resolving Details of the Nonbiomineralized Anatomy of Trilobites Using Computed
    Resolving Details of the Nonbiomineralized Anatomy of Trilobites Using Computed Tomographic Imaging Techniques Thesis Presented in Partial Fulfillment of the Requirements for the Master of Science in the Graduate School of The Ohio State University By Jennifer Anita Peteya, B.S. Graduate Program in Earth Sciences The Ohio State University 2013 Thesis Committee: Loren E. Babcock, Advisor William I. Ausich Stig M. Bergström Copyright by Jennifer Anita Peteya 2013 Abstract Remains of two trilobite species, Elrathia kingii from the Wheeler Formation (Cambrian Series 3), Utah, and Cornuproetus cornutus from the Hamar Laghdad Formation (Middle Devonian), Alnif, Morocco, were studied using computed tomographic (CT) and microtomographic (micro-CT) imaging techniques for evidence of nonbiomineralized alimentary structures. Specimens of E. kingii showing simple digestive tracts are complete dorsal exoskeletons preserved with cone-in-cone concretions on the ventral side. Inferred stomach and intestinal structures are preserved in framboidal pyrite, likely resulting from replication by a microbial biofilm. C. cornutus is preserved in non- concretionary limestone with calcite spar lining the stomach ventral to the glabella. Neither species shows sediment or macerated sclerites of any kind in the gut, which tends to rule out the possibilities that they were sediment deposit-feeders or sclerite-ingesting durophagous carnivores. Instead, the presence of early diagenetic minerals in the guts of E. kingii and C. cornutus favors an interpretation of a carnivorous feeding strategy involving separation of skeletal parts of prey prior to ingestion. ii Dedication This manuscript is dedicated to my parents for encouraging me to go into the field of paleontology and to Lee Gray for inspiring me to continue.
    [Show full text]
  • N. Sp. from the Murray Shale (Lower Cambrian Chilhowee Group) of Tennessee, the Oldest Known Trilobite from the Iapetan Margin of Laurentia
    Journal of Paleontology, 92(3), 2018, p. 442–458 Copyright © 2018, The Paleontological Society. This is an Open Access article, distributed under the terms of the Creative Commons Attribution licence (http://creativecommons.org/ licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited. 0022-3360/18/0088-0906 doi: 10.1017/jpa.2017.155 Buenellus chilhoweensis n. sp. from the Murray Shale (lower Cambrian Chilhowee Group) of Tennessee, the oldest known trilobite from the Iapetan margin of Laurentia Mark Webster,1 and Steven J. Hageman2 1Department of the Geophysical Sciences, University of Chicago, 5734 South Ellis Avenue, Chicago, IL 60637 〈[email protected]〉 2Department of Geology, Appalachian State University, Boone, North Carolina 28608, USA 〈[email protected]〉 Abstract.—The Ediacaran to lower Cambrian Chilhowee Group of the southern and central Appalachians records the rift-to-drift transition of the newly formed Iapetan margin of Laurentia. Body fossils are rare within the Chilhowee Group, and correlations are based almost exclusively on lithological similarities. A critical review of previous work highlights the relatively weak biostratigraphic and radiometric age constraints on the various units within the succession. Herein, we document a newly discovered fossil-bearing locality within the Murray Shale (upper Chilhowee Group) on Chilhowee Mountain, eastern Tennessee, and formally describe a nevadioid trilobite, Buenellus chilhoweensis n. sp., from that site. This trilobite indicates that the Murray Shale is of Montezuman age (provisional Cambrian Stage 3), which is older than the Dyeran (provisional late Stage 3 to early Stage 4) age suggested by the historical (mis)identification of “Olenellus sp.” from within the unit as reported by workers more than a century ago.
    [Show full text]
  • ABSTRACT BOOK a Cura Della Società Geologica Italiana
    https://doi.org/10.3301/ABSGI.2019.04 Milano, 2-5 July 2019 ABSTRACT BOOK a cura della Società Geologica Italiana 3rd International Congress on Stratigraphy GENERAL CHAIRS Marco Balini, Università di Milano, Italy Elisabetta Erba, Università di Milano, Italy - past President Società Geologica Italiana 2015-2017 SCIENTIFIC COMMITTEE Adele Bertini, Peter Brack, William Cavazza, Mauro Coltorti, Piero Di Stefano, Annalisa Ferretti, Stanley C. Finney, Fabio Florindo, Fabrizio Galluzzo, Piero Gianolla, David A.T. Harper, Martin J. Head, Thijs van Kolfschoten, Maria Marino, Simonetta Monechi, Giovanni Monegato, Maria Rose Petrizzo, Claudia Principe, Isabella Raffi, Lorenzo Rook ORGANIZING COMMITTEE The Organizing Committee is composed by members of the Department of Earth Sciences “Ardito Desio” and of the Società Geologica Italiana Lucia Angiolini, Cinzia Bottini, Bernardo Carmina, Domenico Cosentino, Fabrizio Felletti, Daniela Germani, Fabio M. Petti, Alessandro Zuccari FIELD TRIP COMMITTEE Fabrizio Berra, Mattia Marini, Maria Letizia Pampaloni, Marcello Tropeano ABSTRACT BOOK EDITORS Fabio M. Petti, Giulia Innamorati, Bernardo Carmina, Daniela Germani Papers, data, figures, maps and any other material published are covered by the copyright own by the Società Geologica Italiana. DISCLAIMER: The Società Geologica Italiana, the Editors are not responsible for the ideas, opinions, and contents of the papers published; the authors of each paper are responsible for the ideas opinions and con- tents published. La Società Geologica Italiana, i curatori scientifici non sono responsabili delle opinioni espresse e delle affermazioni pubblicate negli articoli: l’autore/i è/sono il/i solo/i responsabile/i. © Società Geologica Italiana, Roma 2019 STRATI 2019 ABSTRACT INDEX ST1.1 History of Stratigraphy in Italian environments (17th – 20th centuries) ........................................
    [Show full text]
  • Feeding Strategy and Locomotion of Cambrian Hyolithides
    Available online at www.sciencedirect.com ScienceDirect Palaeoworld 27 (2018) 334–342 Feeding strategy and locomotion of Cambrian hyolithides a,∗ a b c,d b Hai-Jing Sun , Fang-Chen Zhao , Rong-Qin Wen , Han Zeng , Jin Peng a State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China b Resources and Environmental Engineering College, Guizhou University, Guiyang 550025, China c College of Earth Sciences, University of Chinese Academy of Sciences, No. 19 Yuquan Road, Beijing 100049, China d Department of Paleobiology, National Museum of Natural History, P.O. Box 37012, MRC-121, Washington, DC 20013-7012, USA Received 7 November 2017; received in revised form 8 March 2018; accepted 26 March 2018 Available online 3 April 2018 Abstract The Chengjiang (Cambrian Stage 3) and Balang (Cambrian Stage 4) Konservat-Lagerstätten of South China have produced abundant hyolithide hyoliths; however, little attention has been paid to their feeding strategy and the role it played in the ecosystem. Hyolithides preserved in coprolites from the Chengjiang Biota and associated with a Tuzoia carcass from the Balang Fauna reveal the fluid feces consuming and scavenging strategies of this group. Size distribution of hyolithides demonstrates that their dietary habit is ontogenetically dependent, with juveniles having ingested organic-rich material whereas adult food consumption was more likely by a variety of species-dependent methods The first discovery of hyolithides in association with locomotion traces and burrows indicates they were not only epibenthic vagrants, but also shallow horizontal burrowers. The new discoveries reported herein enhance our understanding of the feeding strategy and other behaviours of Cambrian hyolithides.
    [Show full text]
  • Abstract Volume
    ABSTRACT VOLUME INTERNATIONAL CONFERENCE — ON THE — CAMBRIAN EXPLOSION WALCOTT 2009 — EDITORS — MARTIN R. SMITH LORNA J. O’BRIEN JEAN-BERNARD CARON © 2009 – The Burgess Shale Consortium All rights reserved. No part of this publication may be reproduced, stored in a retrieval system or data base, or transmitted, in any form or by any means, electronic, mechanical, photocopying, or otherwise, without the prior written consent of the publisher. First published in 2009 by the Burgess Shale Consortium, 100 Queen’s Park, Toronto, Ontario M5S2C6, CANADA Publication date: July 31st, 2009 ISBN 978-0-9812885-1-2 National Library of Canada Cataloguing in Publication International conference on the Cambrian explosion (ICCE, Aug 3-8th 2009: Banff, Alberta, Canada) International Conference on the Cambrian Explosion – Abstract Volume; Martin Smith, Lorna O’Brien and Jean-Bernard Caron, Editors. Printed and bound in Canada by Alicos Digital Copy Centre Cover design: Grace Cheong Image credit: Smithsonian Institution Archives (Walcott standing in the Phyllopod Bed Quarry, 1911, cover) WALCOTT 2009 | 3 FOREWORD Welcome to the International Conference on the Cambrian Explosion, 2009. This special meeting commemorates the centenary of the discovery of the Burgess Shale by Charles D. Walcott. We are delighted to welcome a broad spectrum of over 135 Cambrian Explosion workers from across the globe, attending this conference to exchange ideas on current research and to visit the famous localities, part of the Canadian Mountain Parks World Heritage Site. This abstract volume is a compilation of the abstracts for keynote, oral and poster presentations. The suite of abstracts received is a testament to the quality and diversity of current research in this field, one hundred years after the discovery of the first Burgess Shale animals.
    [Show full text]