Hostname: page-component-78c5997874-dh8gc Total loading time: 0 Render date: 2024-11-20T04:40:19.987Z Has data issue: false hasContentIssue false
  • English
  • Français

A teratological pygidium of the Upper Cambrian trilobite Eugonocare (Pseudeugonocare) bispinatum from the Machari Formation, Korea

Published online by Cambridge University Press:  20 May 2016

Jeong Gu Lee ,
Duck K. Choi  and
Brian R. Pratt
Jeong Gu Lee
Affiliation:
1Department of Geological Sciences, Seoul National University, Seoul 151–742, Korea, ,
Duck K. Choi
Affiliation:
1Department of Geological Sciences, Seoul National University, Seoul 151–742, Korea, ,
Brian R. Pratt
Affiliation:
2Department of Geological Sciences, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E2, Canada,
Get access Rights & Permissions [Opens in a new window]

Extract

Abundant examples of exoskeletal abnormalities have been known in various trilobites since Portlock's (1843) first report on a teratological pygidium of Phillipsia ornata (cf. Babcock, 2000). Owen (1985) and Babcock (1993) recognized three types of trilobite malformations: healed injuries, teratological conditions, and pathological conditions. It is not always easy, however, to distinguish between the various types of malformations, especially in case of teratological or pathological conditions. In general, healed injuries are considered to have resulted from trauma during molting (Walcott, 1883; Whittington, 1956; Henningsmoen, 1975; Snajdr, 1981; Owen, 1983; Ramsköld, 1984) or wounds by predatory attack (Ludvigsen, 1977; Rudkin, 1979; Ŝnajdr, 1979, 1981; Owen, 1985; Conway Morris and Jenkins, 1985; Babcock, 1993; Pratt, 1998). Many healed injuries are indicated by broken spine stumps, indented and cicatrized edges of exoskeletons, and callused or regenerated exoskeleton around the broken surface (Ŝnajdr, 1981; Owen, 1983; Babcock, 1993). Teratological conditions are represented primarily by the irregular development of glabellar lobes, cephalic borders, and pygidial border spines, and anomalous number of segments on the thorax and pygidium. For example, Owen (1980) described a teratological cranidium of Calyptaulax norvegicus with two additional lateral glabellar lobes between the l p and 2p lobes. On the other hand, pathological conditions are marked by gall-like swellings and vermiform borings on exoskeletons that are thought to have been caused by diseases or parasitic infestation (Lochman, 1941; Ŝnajdr, 1978; Conway Morris, 1981; Owen, 1985).

Type
Paleontological Note
Information
Journal of Paleontology , Volume 75 , Issue 1 , January 2001 , pp. 216 - 218
Copyright
Copyright © The Paleontological Society

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

Babcock, L. E. 1993. Trilobite malformations and the fossil record of behavioral asymmetry. Journal of Paleontology, 67:217–229.CrossRefGoogle Scholar
Babcock, L. E. 2000. Role of malformations in elucidating the paleobiology of trilobites. Geological Society of America, North-Central Section Abstracts with Programs, 32(4):A3.Google Scholar
Chatterton, B. D. E. 1971. Taxonomy and ontogeny of Siluro-Devonian trilobites near Yass, New South Wales. Palaeontographica, 137A:1–108Google Scholar
Conway Morris, S. 1981. Parasites and the fossil record. Parasitology, 82:489–509.CrossRefGoogle Scholar
Conway Morris, S., and Jenkins, R. J. F. 1985. Healed injuries in Early Cambrian trilobites from South Australia. Alcheringa, 9:167–177.CrossRefGoogle Scholar
Henningsmoen, G. 1975. Moulting in trilobites. Fossils and Strata, 4:179–200.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, 13:85–102.Google Scholar
T., Kobayashi. 1962. The Cambrian-Ordovician formations and faunas of South Korea, Part 9, Palaeontology 8, The Machari fauna. Journal of the Faculty Science, University of Tokyo, Section II, 14:1–152.Google Scholar
Lee, J. G. 1995. Late Cambrian trilobites from the Machari Formation, Yeongweol, Korea. Unpublished Ph.D. thesis. Seoul National University, Seoul, 418 p.Google Scholar
Lee, J. G., and Choi, D. K. 1995. Late Cambrian trilobites from the Machari Formation, Machari-Yeongweol Area, Korea. Journal of the Paleontological Society of Korea, 11:1–46.Google Scholar
Lochman, C. 1941. A pathological pygidium from the Upper Cambrian of Missouri. Journal of Paleontology, 15:324–325.Google Scholar
Ludvigsen, R. 1977. Rapid repair of traumatic injury by an Ordovician trilobite. Lethaia, 10:205–207.CrossRefGoogle Scholar
Neville, A. C. 1975. Biology of the Arthropod Cuticle. Springer-Verlag, New York Heidelberg Berlin, 448 p.CrossRefGoogle Scholar
Owen, A. W. 1980. An abnormal cranidium of the trilobite Calyptaulax norvegicus . Norsk Geologisk Tidsskrift, 60:87–88.Google Scholar
Owen, A. W. 1983. Abnormal cephalic fringes in the Trinucleidae and Harpetidae (Trilobita). Special Papers in Paleontology, 30:241–247.Google Scholar
Owen, A. W. 1985. Trilobite abnormalities. Transactions of the Royal Society of Edinburgh, 76:255–272.CrossRefGoogle Scholar
Palmer, A. R. 1962. Glyptagnostus and associated trilobites in the United States. U. S. Geological Survey Professional Paper 374F, 49 p.Google Scholar
Peng, S. 1992. Upper Cambrian biostratigraphy and trilobite faunas of the Cili-Taoyuan area, northwestern Hunan, China. Association of Australasian Palaeontologists, Memoir 13, 119 p.Google Scholar
Portlock, J. E. 1843. Report on the Geology of the County of Londonderry and Parts of Tyrone and Fermanagh. Andrew Milliken, Dublin and Longman, Brown, Green, and Longmans, London, 784 p.Google Scholar
Pratt, B. R. 1992. Trilobites of the Marjuman and Steptoean stages (Upper Cambrian), Rabbitkettle Formation, southern Mackenzie Mountains, northwest Canada. Paleontolographica Canadiana 9, 179 p.Google Scholar
Pratt, B. R. 1998. Probable predation on Upper Cambrian trilobites and its relevance for the extinction of soft-bodied Burgess Shale-type animals. Lethaia, 31:73–88.CrossRefGoogle Scholar
Ramsköld, L. 1984. Silurian odontopleurid trilobites from Gotland. Palaeontology, 27(2):239–264Google Scholar
Rudkin, D. M. 1979. Healed injuries in Ogygopsis klotzi (Trilobita) from the Middle Cambrian of British Columbia. Royal Ontario Museum, Life Sciences Occasional Paper, 32:1–8.Google Scholar
Rudkin, D. M. 1985. Exoskeletal abnormalities in four trilobites. Canadian Journal of Earth Sciences, 22:479–483.CrossRefGoogle Scholar
Schrank, E. 1969. Odontopleuriden (Trilobita) aus silurischen Geschieben. Berichte der Deutschen Geologischen Gesselschaft für Geologische Wissenschaften, Reihe A: Geologie und Paläontologie, 14:705–726.Google Scholar
Šnajdr, M. 1978. Anomalous carapaces of Bohemian paradoxid trilobites. Sborník Geologických Věd Paleontologie, 20:7–31.Google Scholar
Šnajdr, M. 1979. Two trinucleid trilobites with repair of traumatic injury. Věstiník Ústředního Ústavu Geologického, 54:49–50.Google Scholar
Šnajdr, M. 1981. Bohemian Proetidae with malformed exoskeletons (Trilobita). Sborník Geologických Včd Paleontologie, 24:37–60.Google Scholar
Walcott, C. D. 1883. Injury sustained by the eye of a trilobite at the time of the moulting of the shell. Americal Journal of Science, 62:302.CrossRefGoogle Scholar
Whittington, H. B. 1956. Silicified Middle Ordovician trilobites: the Odontopleuridae. Bulletin of the Museum of Comparative Zoology, Harvard University, 114:155–288.Google Scholar
Zhou, T. M., Liu, Y. R., Meng, X. S., and Sun, Z. H. 1977. Class Trilobita, p. 104–266. In Paleontological Atlas of Central and South China. I, Early Paleozoic. Geological Publishing House, Beijing. (In Chinese)Google Scholar