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The Scottish Carboniferous tetrapod Crassigyrinus scoticus (Lydekker)—cranial anatomy and relationships

Published online by Cambridge University Press:  03 November 2011

J. A. Clack
Affiliation:
University Museum of Zoology, Downing Street, Cambridge, CD2 3EJ, U.K.

Abstract

A new reconstruction of the skull of Crassigyrinus scoticus (Lydekker) is provided, based on newly prepared material. A revised interpretation of the naris shows it in most respects to be like that of other Carboniferous tetrapods, lacking both an anterior tectal and a lateral rostral. However it does incorporate an enlarged septomaxilla, and part of the dorsal surface of the vomer is also visible within the naris of most specimens. Prominent paired buttresses run along the midline of the snout, and a single bowl-shaped interpremaxillary fenestra pierces the snout and palate but is not confluent with the naris or choana. A preopercular is probably absent. A new cladistic analysis places Crassigyrinus with the Viséan genus Whatcheeria, and puts those two taxa as a sister-clade to the anthracosaurs Proterogyrinus and Pholiderpeton. Temnospondyls form a clade with loxommatids, and these two arms form a dichotomy crownward to Greererpeton, Ichthyostega and Acanthostega which are successive stemward plesions.

Type
Research Article
Copyright
Copyright © Royal Society of Edinburgh 1997

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References

Ahlberg, P. E. & Clack, J. A. (submitted ms) Lower jaws, lower tetrapods, a review based on the Devonian genus Acanthostega. Transactions of the Royal Society of Edinburgh.Google Scholar
Ahlberg, P. E. & Milner, A. R. 1994. The origin and early diversification of tetrapods. Nature 368, 507–14.CrossRefGoogle Scholar
Andrews, S. M., Browne, M. A. E., Panchen, A. L. & Wood, S. P. 1977. Discovery of amphibians in the Namurian (Upper Carboniferous) from Fife. Nature 265, 529–32.CrossRefGoogle Scholar
Beaumont, E. H. 1977. Cranial morphology of the Loxommatidae (Amphibia: Labyrinthodontia) Philosophical Transactions of the Royal Society of London B. 280, 29101.Google Scholar
Beaumont, E. H. & Smithson, T. R. (1998 in press) The cranial morphology and relationships of the aberrant Carboniferous amphibian Spathicephalus mirus Watson. Zoological Journal of the Linnean Society.CrossRefGoogle Scholar
Bolt, J. R., Clack, J. A. & Lombard, R. E. 1994. The origin and early evolution of tetrapods: new fossil data and their interpretation. 4th International Congress of Vertebrate Morphology, Chicago, Abstracts. Journal of Morphology 220, 327–8.Google Scholar
Briggs, D. E. G. & Crowther, P. R. 1990. Palaeobiology: a synthesis. Oxford: Blackwell Scientific Publications.Google Scholar
Carroll, R. L. 1967. Labyrinthodonts from the Joggins fauna. Journal of Paleontology 41, 111–42.Google Scholar
Carroll, R. L. 1970. The ancestry of reptiles. Philosophical Transactions of The Royal Society of London B257, 267308.Google Scholar
Carroll, R. L. 1995. Problems of the phylogenetic analysis of Paleozoic choanates. Bulletin du Museum National d'Histoire Naturelle Paris 17, 389445.Google Scholar
Clack, J. A. 1987. Pholiderpeton scutigerum Huxley, an amphibian from the Yorkshire Coal Measures. Philosophical Transactions of The Royal Society of London B318, 1107.Google Scholar
Clack, J. A. 1994. Acanthostega gunnari, a Devonian tetrapod from Greenland; the snout, palate and ventral parts of the braincase, with a discussion of their significance. Meddelelser om Gronland Geoscience 31, 124.Google Scholar
Clack, J. A. 1996. The palate of Crassigyrinus scoticus, a primitive tetrapod from the Lower Carboniferous of Scotland. In Milner, A. R. (ed.) Studies on Carboniferous and Permian vertebrates, Special Papers in Palaeontology. 52, 5564. London: Palaeontological Association.Google Scholar
Coates, M. I. 1996. The Devonian tetrapod Acanthostega gunnari Jarvik: postcranial anatomy, basal tetrapod interrelationships and patterns of skeletal evolution. Transactions of the Royal Society of Edinburgh: Earth Sciences 87, 363421.CrossRefGoogle Scholar
Dilkes, D. 1993. Biology and evolution of the nasal region in trematopid amphibians. Palaeontology 36, 839–54.Google Scholar
Forey, P. L., Gardiner, B. G. & Patterson, C. 1991. The lungfish, the coelacanth and the cow revisited. In Schultze, H-P. & Trueb, L. (eds) Origins of the higher groups of tetrapods, 145–74. Ithaca: Comstock Publishing Associates.Google Scholar
Godfrey, S. J. 1988. Isolated tetrapod remains from the Carboniferous of West Virginia. Kirtlandia 43, 2736.Google Scholar
Holmes, R. 1980. Proterogyrinus scheeli and the early evolution of the labyrinthodont pectoral limb. In Panchen, A. L. (ed.) The terrestrial environment and the origin of land vertebrates, 351–76. London: Academic Press.Google Scholar
Holmes, R. B., Carroll, R. L. & Reisz, R. R. (in press) The first articulated skeleton of Dendrerpeton acadianum (Temnospondyli, Dendrerpetontidae) from Joggins (Westphalian A) Nova Scotia, and a review of its relationships. Journal of Vertebrate Paleontology.Google Scholar
Jarvik, E. 1944. On the dermal bones, sensory canals and pit-lines of the skull of Eusthenopteron foordii Whiteaves, with some remarks on E. säve-söderberghi Jarvik. Kungliga Svenska Vetenskapakademiens Handlingar 21, 148.Google Scholar
Jarvik, E. 1980. Basic structure and evolution of vertebrates. New York: Academic Press.Google Scholar
Jarvik, E. 1996. The Devonian tetrapod Ichthyostega. Fossils and Strata 40, 1213.CrossRefGoogle Scholar
Laurin, M. & Reisz, R. R. 1997. A new perspective on tetrapod phylogeny. In Sumida, S. S. & Martin, K. L. M. (eds) Amniote origins—completing the transition to land, 959. London: Academic Press.CrossRefGoogle Scholar
Lebedev, O. A. & Coates, M. I. 1995. The postcranial skeleton of the Devonian tetrapod Tulerpeton curtum Lebedev. Zoological Journal of the Linnean Society 114, 307–48.CrossRefGoogle Scholar
Lombard, R. E. & Bolt, J. R. 1995. A new primitive tetrapod, Whatcheeria deltae, from the Lower Carboniferous of Iowa. Palaeontology 38, 471–94.Google Scholar
Long, J. A. 1990. Heterochrony and the origin of tetrapods. Lethaia 23, 157–66.CrossRefGoogle Scholar
Maddison, W. P. & Maddison, D. R. 1992. MacClade. Version 3.0 analysis of phylogeny and character evolution. Sunderland, MA: Sinauer Associates.Google Scholar
Milner, A. C. & Lindsay, W. 1998 in press. Postcranial remains of Baphetes and their bearing on the relationships of the Baphetidae (= Loxommatidae). Zoological Journal of the Linnean Society.CrossRefGoogle Scholar
Milner, A. R. & Sequeira, S. E. K. 1994. The temnospondyl amphibians from the Viséan of East Kirkton, West Lothian, Scotland. Transactions of the Royal Society of Edinburgh: Earth Sciences 84, 331–62.CrossRefGoogle Scholar
Panchen, A. L. 1967. The nostrils of choanate fishes and early tetrapods. Biological Reviews 42, 374420.CrossRefGoogle ScholarPubMed
Panchen, A. L. 1973. On Crassigyrinus scoticus Watson, a primitive amphibian from the Lower Carboniferous of Scotland. Palaeontology 16, 179–93.Google Scholar
Panchen, A. L. 1985. On the amphibian Crassigyrinus scoticus Watson from the Carboniferous of Scotland. Philosophical Transactions of the Royal Society of London B309, 461568.Google Scholar
Panchen, A. L. & Smithson, T. R. 1990. The pelvic girdle and hind limb of Crassigyrinus scoticus (Lydekker) from the Scottish Carboniferous and the origin of the tetrapod pelvic skeleton. Transactions of the Royal Society of Edinburgh: Earth Sciences 81, 3144.CrossRefGoogle Scholar
Romer, A. S. 1947. Review of the Labyrinthodontia. Bulletin of the Museum of Comparative Zoology, Harvard 99, 1168.Google Scholar
Smithson, T. R. 1982. The cranial morphology of Greererpeton burkemorani (Amphibia: Temnospondyli). Zoological Journal of the Linnean Society 76, 2990.CrossRefGoogle Scholar
Swofford, D. L. 1993. PAUP: Phylogenetic analysis using parsimony version 3.1. Computer program distributed by the Illinois Natural History Survey, Champaign, Illinois.Google Scholar
Vorobyeva, E. I. & Schultze, H-P. 1991. Description and systematics of panderichthyid fishes with comments on their relationship to tetrapods. In Schultze, H-P. & Trueb, L. (eds) Origins of the higher groups of tetrapods, 68109. Ithaca: Comstock Publishing Associates.Google Scholar
Watson, D. M. S. 1929. The Carboniferous Amphibia of Scotland, Palaeontologica Hungarica 1, 219–52.Google Scholar