Hostname: page-component-cd9895bd7-jn8rn Total loading time: 0 Render date: 2024-12-23T07:21:59.711Z Has data issue: false hasContentIssue false

A revised ontogeny of the early Ordovician trilobite Leptoplastides salteri (Callaway, 1877)

Published online by Cambridge University Press:  20 November 2018

Kristina MÅNSSON*
Affiliation:
Department of Geology, Lund University, Sölvegatan 12, SE-223 62 Lund, Sweden. Email: [email protected]
Euan N. K. CLARKSON
Affiliation:
School of Geosciences, University of Edinburgh, Kings Buildings, West Mains Road, Edinburgh EH9 3JW, Scotland, UK. Email: [email protected]
*
*Corresponding author

Abstract

The ontogeny of the pelturine olenid trilobite Leptoplastides salteri (Callaway, 1877) from the Shineton Shales, Shropshire, England, was first described in 1925 by Frank Raw. Since that time, scanning electron microscopy and other new technologies have revealed many more details of structure, of early developmental stages in particular, than were available to Raw. Whereas protaspides are not preserved and the state of preservation is less than perfect for the smallest meraspides, we have established that the latter had an array of delicate, long thoracic and pygidial spines, as well as paired procranidial spines, which disappear by meraspid degree 8. Raw's reconstructions of early meraspides, and his measurements of the early stages in development, are here amended in the light of new information. Dorsal spines in the adult are much more highly developed than have been documented in any other olenid. The hypostome is preserved in place in several specimens. Initially conterminant (attached to the doublure), it becomes natant (free) in late meraspid to early holaspid stages of development, with its anterior contour fitting exactly to that of the glabella. The ecology of the widespread Leptoplastides is best known from very extensive sections in South America, which provide a useful basis for comparison. It was well adapted to a range of environments, both oxygenated and dysoxic, and is usually the dominant taxon in the biofacies in which it is found.

Type
Articles
Copyright
Copyright © The Royal Society of Edinburgh 2018 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

5. References

Acenolaza, G. F., Tortello, M. F. & Rábano, I. 2001. The eyes of the early Tremadoc olenid trilobite Jujuyaspis keideli Kobayashi, 1936. Journal of Paleontology 75, 346350.Google Scholar
Adrain, J. 2011. Class Trilobita Walch, 1771. In Zhang, Z. G. (ed.) Animal biodiversity, an outline of higher-level classification and taxonomic richness. Zootaxa 3148, 104109. Orlando, FL: Magnolia Press.Google Scholar
Ahlberg, P., Szaniawski, H., Clarkson, E. N. K. & Bengtson, S. 2005. Phosphatised olenid trilobites from Västergötland, Sweden. Acta Palaeontological Polonica 50, 429440.Google Scholar
Ahlberg, P., Månsson, K., Clarkson, E. N. K. & Taylor, C. M. 2006. Faunal turnovers and trilobite morphologies in the Upper Cambrian Leptoplastus zone at Andrarum, southern Sweden. Lethaia 39, 97110.Google Scholar
Balseiro, D., Waisfeld, B. G. & Buatois, L. A. 2011. Unusual trilobite facies from the Lower Ordovician of the Argentine Cordillera Oriental: new insights into olenid palaeoecology. Lethaia 44, 5875.Google Scholar
Balseiro, D. & Marengo, L. 2008. Tremadocian trilobite assemblages from the Argentine Cordillera Oriental. A preliminary analysis. In Rabáno, I., Gozalo, R. & García-Bellido, D. (eds) Advances in trilobite research, 3340. Cuadernos del Museo Geominero, vol. 9. Madrid: Instituto Geológico y Minero de España.Google Scholar
Barrande, J. 1852. Systéme Silurien du Centre de la Bohême: 1ere Partie, Crustacés, Trilobites, 1. Prague, Paris. 935 pp.Google Scholar
Bird, C. & Clarkson, E. N. K. 2003. Observations on the ontogeny of Peltura scarabaeoides westergaardi Henningsmoen, 1957. GFF 125, 177190.Google Scholar
Bulman, O. M. B. & Rushton, A. W. A. 1973. Tremadoc faunas from boreholes in central England. Bulletin of the Geological Society of Great Britain 43, 140.Google Scholar
Burmeister, H. 1843. Die Organisation der Trilobiten aus ihren lebenden Verwandten entwickelt; nebst einer systematischen Uebersicht aller zeiter beschriebenen Arten. Berlin. 148 pp.Google Scholar
Callaway, C. 1874. On the occurrence of a Tremadoc area near the Wrekin in South Shropshire, with description of a new fauna. Quarterly Journal of the Geological Society of London 30, 196.Google Scholar
Callaway, C. 1877. On a new area of Upper Cambrian rocks in South Shropshire, with a description of a new fauna. Quarterly Journal of the Geological Society of London 33, 652672.Google Scholar
Clarkson, E. N. K. 1973. Morphology and evolution of the eye in Upper Cambrian Olenidae (Trilobita). Palaeontology 16, 735765.Google Scholar
Clarkson, E. N. K., Taylor, C. M. & Ahlberg, P. 1997. Ontogeny of the trilobite Parabolina spinulosa (Wahlenberg, 1818) from the upper Cambrian Alum Shales of Sweden. Transactions of the Royal Society of Edinburgh 88, 6989.Google Scholar
Clarkson, E. N. K., Ahlgren, J. & Taylor, C. M. 2003. Structure, ontogeny, and moulting of the olenid trilobite Ctenopyge (eoctenopyge) angusta Westergård, 1922 from the upper Cambrian of Västergötland, Sweden. Palaeontology 47, 127.Google Scholar
Clarkson, E. N. K., Ahlgren, J. & Taylor, C. M. 2004. Structure, ontogeny, and functional morphology of some spiny Ctenopyge species from Västergötland, Sweden. Transactions of the Royal Society of Edinburgh: Earth Sciences 94, 115143.Google Scholar
Clarkson, E. N. K. & Ahlberg, P. 2002. Ontogeny and morphology of a new, miniaturised and spiny olenid trilobite from the upper Cambrian of southern Sweden. Palaeontology 45, 122.Google Scholar
Clarkson, E. N. K. & Taylor, C. M. 1995. Ontogeny of the trilobite Olenus wahlenbergi Westergård, 1922, from the Upper Cambrian Alum Shales of Andrarum, Skåne, Sweden. Transactions of the Royal Society of Edinburgh: Earth Sciences 86, 1334.Google Scholar
Fortey, R. A. 1990. Ontogeny, hypostome attachment, and trilobite classification. Palaeontology 33, 529576.Google Scholar
Fortey, R. A. & Owens, R. M. 1991. A trilobite fauna from the highest Shineton Shales in Shropshire, and the correlation of the latest Tremadoc. Geological Magazine 128, 437464.Google Scholar
Hawle, J. & Corda, A. J. C. 1847. Prodrom einer Monographie der böhmischen Trilobiten. Königliche böhmischen Gesellschaft der Wissenschaften Abhandlung 5, 176.Google Scholar
Henningsmoen, G. 1957. The trilobite family Olenidae. Skrifter utgitt av Det Norske Videnskaps Akademi I Osl. 1. Matematisk-Videnskapelig Klasse 1957, 1–303.Google Scholar
Kobayashi, T. 1936. On the Parabolinella fauna from Province Jujuy, Argentina with a note on the Olenidae. Japanese Journal of Geology and Geography 13, 85102.Google Scholar
Lake, P. 1919. A monograph of the British Cambrian trilobites, 89120. Monograph of the Palaeontographical Society 343, part of vol. 71 for 1917.Google Scholar
Lake, P. 1932. A monograph of the British Cambrian trilobites, 149172. Monograph of the Palaeontographical Society 385, part of vol. 84 for 1930.Google Scholar
Lake, P. 1946. A monograph of the British Cambrian trilobites, 333350. Monograph of the Palaeontographical Society 432, part of vol. 99 for 1945.Google Scholar
Månsson, K. 1998. Middle Ordovician olenid trilobites (Triarthrus green and Porterfieldia cooper) from Jämtland, central Sweden. Transactions of the Royal Society of Edinburgh; Earth Sciences 89, 4762.Google Scholar
Månsson, K. & Clarkson, E. N. K. 2012. Ontogeny of the upper Cambrian (Furongian) olenid trilobite Protopeltura aciculata (Angelin, 1854) from Skåne and Västergötland, Sweden. Palaeontology 55, 887901.Google Scholar
Månsson, K. & Clarkson, E. N. K. 2016. Early ontogeny of the Furongian (Cambrian) olenid trilobites Sphaerophthalmus alatus (Boeck, 1838) and Ctenopgye (mesoctenopyge) tumida Westergård, 1922 from Bornholm, Denmark. Transactions of the Royal Society of Edinburgh: Earth and Environmental Science 106, 171183.Google Scholar
Morris, S. F. 1988. A review of British trilobites, including a synoptic revision of Salter's monograph. Monograph of the Palaeontographical Society 574, 1–316.Google Scholar
Raw, F. 1908. The trilobite fauna of the Shineton Shales. Reports of the British Association for the Advancement of Science 1907, 511513.Google Scholar
Raw, F. 1925. The development of Leptoplastus salteri (Callaway) and of other trilobites (Olenidae, Ptychoparidae, Conocoryphidae, Paradoxidae, Phacopidae, and Mesonacidae). Quarterly Journal of the Geological Society of London 81, 223324.Google Scholar
Raw, F. 1927. The ontogenies of trilobites, and their significance. American Journal of Science 104, 7–35, 131149.Google Scholar
Salter, J. W. 1866. A monograph of the British trilobites of the Cambrian, Silurian and Devonian formations (3). Monograph of the Palaeontographical Society 77, 129176, part of vol 18 for 1864.Google Scholar
Schoenemann, B. & Clarkson, E. N. K. 2015. Eyes and vision in the coeval Furongian trilobites Sphaerophthalmus alatus (Boeck, 1838) and Ctenopyge (mesoctenopyge) tumida westergård, 1822. Palaeontology 58, 133140.Google Scholar
Smith, N. J. P. & Rushton, A. W. A. 1993. Cambrian and Ordovician stratigraphy related to structure and seismic profiles in the western part of the English Midlands. Geological Magazine 130, 665671.Google Scholar
Størmer, L. 1942. Studies on trilobite morphology. Part 2. The larval development, the segmentation and the sutures, and their bearing on trilobite classification. Norsk Geologisk Tidsskrift 21, 49164.Google Scholar
Stubblefield, C. J. 1926. Notes on the development of a trilobite Shumardia pusilla (Sars). Journal of the Linnean Society (Zoology) 36, 345372.Google Scholar
Stubblefield, C. J. & Bulman, O. M. B. 1927. The Shineton Shales of the Wrekin district, with notes on their development in other parts of Shropshire and Herefordshire. Quarterly Journal of the Geological Society of London 83, 96146.Google Scholar
Thomas, H. H. 1900. Fossils in the Oxford University Museum, 4. Notes on some undescribed Trilobites. Quarterly Journal of the Geological Society of London 56, 616619.Google Scholar
Tortello, M. F. & Clarkson, E. N. K. 2003. Structure, ontogeny and moulting of the Early Ordovician olenid trilobite Jujuyaspis keideli from northwestern Argentina. Ameghiniana 40, 257275.Google Scholar
Tortello, M. F. & Clarkson, E. N. K. 2008. Ontogeny, structure and moulting of Parabolina frequens argentina (Kayser) (Trilobita, Olenidae) from the Furongian of northwestern Argentina. Ameghiniana 45, 1331.Google Scholar
Tortello, M. F. & Esteban, S. B. 2016. Early Ordovician trilobites from the Iruya area (Cordillera Oriental), northwestern Argentina and their stratigraphical significance. Journal of Paleontology 90, 923958.Google Scholar
Wahlenberg, G. 1818. Petrificata tellaris svecanae. Nova Acta Regiae Societatis Scientarum Upsaliensis 8, 1116.Google Scholar
Waisfeld, B. G. & Balseiro, D. 2016. Decoupling of local and regional dominance in trilobite assemblages from the northwestern Argentina: new insights into Cambro-Ordovician ecological changes. Lethaia 49, 379392.Google Scholar
Walch, J. E. I. 1771. Die Naturgeschichte der versteinerungen zur erläuterung der Knorrischen Sammlung von Merkwürdigkeiten der Natur. Nürnberg, vol. 3 of Knorr, G. W. & Walch, J. E. I., 17681774. Nürnberg.Google Scholar
Whittington, H. B. 1959. Ontogeny of Trilobita. In Moore, R. C. (ed.) Treatise on invertebrate paleontology. Part O. Arthropoda 1, O127–44. Boulder, CO and Lawrence, KA: Geological Society of America and University of Kansas Press.Google Scholar
Żylińska, A. 2001. Late Cambrian trilobites from the Holy Cross Mountains central Poland. Acta Geologica Polonica 51, 333383.Google Scholar
Żylińska, A., Weidner, T., Ahlgren, J. & Ahlberg, P. 2015. Exotic trilobites from the uppermost Cambrian Series 3 and lower Furongian of Sweden. Acta Palaeontologica Polonica 65, 2167.Google Scholar