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Ontogeny and ventral median suture of the ptychaspidid trilobite Asioptychaspis subglobosa (Sun, 1924) from the Furongian (Upper Cambrian) Hwajeol Formation, Korea

Published online by Cambridge University Press:  14 July 2015

Tae-Yoon Park  and
Duck K. Choi
Tae-Yoon Park
Affiliation:
School of Earth and Environmental Sciences, Seoul National University, Seoul 151—747, Korea, ,
Duck K. Choi
Affiliation:
School of Earth and Environmental Sciences, Seoul National University, Seoul 151—747, Korea, ,
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Abstract

The order Asaphida has been characterized by the possession of a globular protaspis and a ventral median suture. the superfamily Dikelocephaloidea was included in the Asaphida, although there has been no reliable ontogenetic information for this superfamily, and thus whether dikelocephaloids had a protaspis of globular shape has remained unclear. the ontogenetic study of the dikelocephaloid trilobite, Asioptychaspis subglobosa, from Korea reveals that the protaspis of A. subglobosa is not of globular morphology but of general benthic adult-like morphology, heralding that the Dikelocephaloidea may not be closely related to other trilobite groups within the Order Asaphida. This protaspid morphology is clearly distinguished from the highly globular protaspis of the Remopleuridioidea, which has been considered the sister group to the Dikelocephaloidea. in addition, the ontogenetic development of the free cheeks shows that A. subglobosa possessed anteriorly yoked free cheeks during the early phase of development but formed a ventral median suture by splitting the yoked cheeks in the later phase of ontogeny. This contrasts with the previously suggested mode of ventral median suture formation of the Order Asaphida. This alternative mode of ventral median suture formation of A. subglobosa, along with non-asaphoid protaspid morphology, warrants removal of the Dikelocephaloidea from the current Order Asaphida. This study further demonstrates that the ventral median suture did not evolve only once in the evolutionary history of trilobites. With the addition of the mode here documented for Asioptychaspis, the ventral median suture is now known to have developed independently and in a different fashion at least three times in the history of Cambrian trilobites.

Type
Research Article
Information
Journal of Paleontology , Volume 84 , Issue 2 , March 2010 , pp. 309 - 320
Copyright
Copyright © The Paleontological Society 

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References

Adrain, J. M. and Westrop, S. R.. 2004. A late Cambrian (Sunwaptan) silicified trilobite fauna from Nevada. Bulletins of American Paleontology, 365:1–56.Google Scholar
Adrain, J. M. and Westrop, S. R.. 2005. Late Cambrian ptychaspidid trilobites from western Utah: implications for trilobite systematics and biostratigraphy. Geological Magazine, 142:377–398.CrossRefGoogle Scholar
Adrain, J. M., Peters, S. E., and Westrop, S. R.. 2009. The Marjuman trilobite Cedarina Lochman: thoracic morphology, systematics, and new species from western Utah and eastern Nevada, USA. Zootaxa, 2218:35–58.CrossRefGoogle Scholar
Chatterton, B. D. E. and Ludvigsen, R.. 1998. Upper Steptoean (Upper Cambrian) trilobites from the McKay Group of southeastern British Columbia, Canada. The Paleontological Society Memoir 49:1–43.Google Scholar
Chatterton, B. D. E. and Speyer, S. E.. 1997. Ontogeny, p. 173–247. In Kaesler, R. L. (ed.), Treatise on Invertebrate Paleontology, Pt. O, Arthropoda 1, Trilobita 1 (Revised). Geological Society of America and University of Kansas Press, Lawrence.Google Scholar
Chatterton, B. D. E., Speyer, S. E., Hunt, A. S., and Fortey, R. A.. 1994. Ontogeny and relationships of Trinucleoidea (Trilobita). Journal of Paleontology, 68:523–540.CrossRefGoogle Scholar
Choi, D. K. 1998. The Yongwol Group (Cambrian–Ordovician) redefined: A proposal for the stratigraphic nomenclature of the Choson Supergroup. Geosciences Journal, 2:220–234.CrossRefGoogle Scholar
Choi, D. K., Chough, S. K., Kwon, Y. K., Lee, S.-B., Woo, J., Kang, I., Lee, H. S., Lee, S. M., Sohn, J. W., Shinn, Y. J., and Lee, D.-J.. 2004. Taebaek Group (Cambrian–Ordovician) in the Seokgaejae section, Taebaeksan Basin: A refined lower Paleozoic stratigraphy in Korea. Geosciences Journal, 8:125–151.CrossRefGoogle Scholar
Fortey, R. A. 1990. Ontogeny, hypostome attachment and trilobite classification. Palaeontology, 33:529–576.Google Scholar
Fortey, R. A. and Chatterton, B. D. E.. 1988. Classification of the trilobite suborder Asaphina. Palaeontology, 31:165–222.Google Scholar
Hall, J. 1863. Preliminary notice of the fauna of the Potsdam Sandstone; with remarks upon the previously known species of fossils and descriptions of some new ones, from the sandstone of the Upper Mississippi Valley. New York State Cabinet of Natural History, 16th Annual Report, Appendix D, Contributions to Palaeontology, p. 119–184.Google Scholar
Hu, C.-H. 1971. Ontogeny and sexual dimorphism of Lower Paleozoic Trilobita. Palaeontographica Americana, 44:29–155.Google Scholar
Hughes, N. C., Minelli, A., and Fusco, G.. 2006. The ontogeny of trilobite segmentation: a comparative approach. Paleobiology, 32:602–627.CrossRefGoogle Scholar
Hupé, P. 1953. Classe des Trilobites. Traité de Paléontologie, 3:33–246.Google Scholar
Kobayashi, T. 1933. Upper Cambrian of the Wuhutsui basin, Liaotung, with special reference to the limit of Chaumitien (or Upper Cambrian) of eastern Asia and its subdivision. Japanese Journal of Geology and Geography, 11:55–155.Google Scholar
Kwon, Y. K., Chough, S. K., Choi, D. K., and Lee, D. J.. 2006. Sequence stratigraphy of the Taebaek Group (Cambrian–Ordovician), mideast Korea. Sedimentary Geology, 192:19–55.CrossRefGoogle Scholar
Lochman, C. 1964. Upper Cambrian faunas from the subsurface Deadwood formation, Williston Basin, Montana. Journal of Paleontology, 38:33–60.Google Scholar
Lochman, C. and Hu, C.-H.. 1959. A Ptychaspis faunule from the Bear River Range, southeastern Idaho. Journal of Paleontology, 33:404–427.Google Scholar
Park, T.-Y. and Choi, D. K.. 2009. Post-embryonic development of the Furongian (late Cambrian) trilobite Tsinania canens: implications for life mode and phylogeny. Evolution & Development, 11:441–455CrossRefGoogle ScholarPubMed
Park, T.-Y. and Choi, D. K.. In press. Two middle Cambrian diceratocephalid trilobites, Cyclolorenzella convexa and Diceratocephalus cornutus, from Korea: development and functional morphology. Lethaia. (2009, DOI: 10.1111/j.1502-3931.2009.00168.x)CrossRefGoogle Scholar
Raymond, P. E. 1924. New Upper Cambrian and Lower Ordovician trilobites from Vermont. Proceedings of the Boston Society of Natural History, 37:389–466.Google Scholar
Rasetti, F. 1944. Upper Cambrian trilobites from the Levis Conglomerate. Journal of Paleontology, 18:229–258.Google Scholar
Salter, J. W. 1864. A monograph of the British trilobites from the Cambrian, Silurian and Devonian Formations. Palaeontographic Society of London Monographs, 1–80.Google Scholar
Sohn, J. W. and Choi, D. K.. 2005. Revision of the Upper Cambrian trilobite biostratigraphy of the Sesong and Hwajeol formations, Taebaek group, Korea. Journal of the Paleontological Society of Korea, 21:195–200. (In Korean with English abstract)Google Scholar
Sohn, J. W. and Choi, D. K.. 2007. Furongian trilobites from the Asioptychaspis and Quadraticephalus zones of the Hwajeol Formation, Taebaeksan Basin, Korea. Geosciences Journal, 11:297–314.CrossRefGoogle Scholar
Sun, Y. C. 1924. Contributions to the Cambrian faunas of North China. Palaeontologia Sinica, Series B, 1:1–109.Google Scholar
Walcott, C. D. 1905. Cambrian faunas of China. Proceedings of the U.S. National Museum, 29:1–106.Google Scholar
Westrop, S. R. 1986. Trilobites of the Upper Cambrian Sunwaptan Stage, southern Canadian Rocky Mountains, Alberta. Palaeontographica Canadiana, 3:1–179.Google Scholar
Whittington, H. B. 2003. The upper Cambrian trilobites Plethopeltis and Leiocoryphe: morphology, paedomorphism, classification. Journal of Paleontology, 77:698–705.2.0.CO;2>CrossRefGoogle Scholar
Whittington, H. B. 2007. Reflections on the classification of the Trilobita. In Mikulic, D. G. and Landing, E. (eds.), Fabulous Fossils–300 yr of Worldwide Research on Trilobites. New York State Museum Bulletin, 507:225–230.Google Scholar
Whittington, H. B. and Kelly, S. R. A.. 1997. Morphological terms applied to Trilobita, p. 313–329. In Kaesler, R. L. (ed.), Treatise on Invertebrate Paleontology, Trilobita, Pt. O. (Revised), Geological Society of America and University of Kansas Press, Lawrence.Google Scholar
Zhang, W. T. and Jell, P. A.. 1987. Cambrian trilobites of North China: Chinese trilobites housed in the Smithsonian Institution. Science Press, Beijing, 459 p.Google Scholar