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Palate and braincase of Whatcheeria deltae Lombard & Bolt, 1995

Published online by Cambridge University Press:  18 December 2018

John R. BOLT  and
R. Eric LOMBARD
John R. BOLT
Affiliation:
Department of Geology, Field Museum of Natural History, 1400 S Lake Shore Drive, Chicago, IL 60605, USA.
R. Eric LOMBARD*
Affiliation:
Department of Organismal Biology and Anatomy, The University of Chicago, 1027 E 57th Street, Chicago, IL 60637, USA. Email: elombard@uchicago.edu
*
*Corresponding author
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Abstract

The reconstructed palate of Whatcheeria deltae indicates a skull that was unusually narrow: at least 2.2 times longer than wide if the pterygoids are conservatively placed in the horizontal plane. This maximum width is narrower than any other early tetrapod reconstructed so far. Rotating the pterygoids to produce a vaulted palate would produce an even narrower skull. Primitive palatal features include very narrow interpterygoid vacuities and a vomer, palatine, and ectopterygoid with fang-sized replacement pairs. It is derived in that there is no anterior palatal fenestra and the premaxilla has a substantial palatal shelf – a combination of characters shared only with Proterogyrinus among early tetrapods. There is a possible septomaxilla in one specimen. Whatcheeria differs from and is more derived than Pederpes, its likely sister taxon, in that only the pterygoid is covered with denticles, the vomer, palatine, and ectopterygoid containing labyrinthine teeth only. Reconstructed dental occlusion indicates that the large choana apparently accommodated the large dentary fangs; this would be a unique feature among early tetrapods. The palatal ramus of the pterygoid is longer than the quadrate ramus, which does not have a descending flange. Like Meckel's cartilage in the lower jaw, the palatoquadrate is fully ossified in larger specimens, such that in a posterior view of the skull the pterygoid is mostly hidden from sight by the epipterygoid. The ossified neurocranium consists of the basiparasphenoid and basioccipital; no ossified sphenethmoid has been found. Remains of otic capsules are partial, crushed, and smeared, so no useful morphology is available. The stapes appears to be more columnar and less plate-like than in many other primitive, early tetrapods.

Keywords

AsbianchoanafossilMississippianocclusionskulltetrapodswhatcheeriids
Type
Articles
Information
Earth and Environmental Science Transactions of The Royal Society of Edinburgh , Volume 109 , Issue 1-2: Fossils, Function and Phylogeny: Papers on Early Vertebrate Evolution in Honour of Professor Jennifer A. Clack , March 2018 , pp. 177 - 200
Copyright
Copyright © The Royal Society of Edinburgh 2018 

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References

6. References

Bolt, J. R. & Lombard, R. E. 1985. Evolution of the amphibian tympanic ear and the origin of frogs. Biological Journal of the Linnean Society 24, 83–99.Google Scholar
Bolt, J. R. & Lombard, R. E. 2000. Palaeobiology of Whatcheeria deltae, a primitive Mississippian tetrapod. In Heatwole, H. (ed.) Amphibian biology, 4, Paleobiology, 1044–1052. Chipping Norton, Australia: Surrey Beatty and Sons.Google Scholar
Carroll, R. L. 1980. The hyomandibular as a supporting element in the skull of primitive tetrapods. In Panchen, A. L. (ed.) The terrestrial environment and the origin of land vertebrates, 293–317. London: Academic Press.Google Scholar
Clack, J. A. 1983. The stapes of the Coal Measures embolomere Pholiderpeton scutigerum Huxley (Amphibia: Anthracosauria) and otic evolution in early tetrapods. Zoological Journal of the Linnean Society 79, 121–148.Google Scholar
Clack, J. A. 1987. Pholiderpeton scutigerum Huxley, an amphibian from the Yorkshire Coal Measures. Philosophical Transactions of the Royal Society of London, Series B 318, 1–107.Google Scholar
Clack, J. A. 1989. Discovery of the earliest-known tetrapod stapes. Nature 342, 425–427.Google Scholar
Clack, J. A. 1992. The stapes of Acanthostega gunnari and the role of the stapes in early tetrapods. In Webster, D. B., Fay, R. R. & Popper, A. (eds) The evolutionary biology of hearing, 405–420. New York: Springer-Verlag.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 Grønland: Geoscience 31, 1–24.Google Scholar
Clack, J. A. 1998. The Scottish Carboniferous tetrapod Crassigyrinus scoticus (Lydekker) – cranial anatomy and relationships. Transactions of the Royal Society of Edinburgh: Earth Sciences 88, 127–142.Google Scholar
Clack, J. A. 2002a. An early tetrapod from ‘Romer's Gap'. Nature 418, 72–76.Google Scholar
Clack, J. A. 2002b. The dermal skull roof of Acanthostega gunnari, an early tetrapod from the Late Devonian. Transactions of the Royal Society of Edinburgh: Earth Sciences 93, 17–33.Google Scholar
Clack, J. A. 2003a. A new baphetid (stem tetrapod) from the Upper Carboniferous of Tyne and Wear, U. K., and the evolution of the tetrapod occiput. Canadian Journal of Earth Sciences 40, 483–498.Google Scholar
Clack, J. A. 2003b. A revised reconstruction of the dermal skull roof of Acanthostega gunnari, an early tetrapod from the Late Devonian. Transactions of the Royal Society of Edinburgh: Earth Sciences 93, 163–165.Google Scholar
Clack, J. A., Ahlberg, P. E., Finney, S. M., Dominguez Alonso, P., Robinson, J. & Ketcham, R. A. 2003. A uniquely specialized ear in an early tetrapod. Nature 425, 65–69.Google Scholar
Clack, J. A., Witzmann, F., Müller, J. & Snyder, D. 2012. A colosteid-like early tetrapod from the St. Louis Limestone (Early Carboniferous, Meramecian), St. Louis, Missouri, USA. Fieldiana Life and Earth Sciences 5, 17–39.Google Scholar
Clack, J. A., Bennett, C. E., Carpenter, D. K., Davies, S. J., Fraser, N. C., Kearsey, T. I., Marshall, J. E. A., Millward, D., Otoo, B. K. A., Reeves, E. J., Ross, A. J., Ruta, M., Smithson, K. Z., Smithson, T. R. & Walsh, S. A. 2016. Phylogenetic and environmental context of a Tournaisian tetrapod fauna. Nature Ecology and Evolution 1, 0002.Google Scholar
Clack, J. A. & Finney, S. M. 2005. Pederpes finneyae, an articulated tetrapod from the Tournaisian of Western Scotland. Journal of Systematic Palaeontology 2, 311–346.Google Scholar
Clack, J. A. & Holmes, R. 1988. The braincase of the anthracosaur Archeria crassidisca with comments on the interrelationships of primitive tetrapods. Palaeontology 31, 85–107.Google Scholar
Daeschler, E. B., Shubin, N. H. & Jenkins, F. A. Jr. 2006. A Devonian tetrapod-like fish and the evolution of the tetrapod body plan. Nature 440, 757–763.Google Scholar
Goodrich, E. S. 1958. Studies on the structure and development of vertebrates, I, i–lxix + 485 pp. New York: Dover Publications Inc.Google Scholar
Holmes, R. 1984. The carboniferous amphibian Proterogyrinus scheelei Romer, and the early evolution of tetrapods. Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences 306, 431–524.Google Scholar
Holmes, R. 1989. The skull and axial skeleton of the Lower Permian anthracosauroid amphibian Archeria crassidisca. Palaeontographica, Abteilung A 207, 161–206.Google Scholar
Huttenlocker, A. K., Pardo, J. D., Small, B. J. & Anderson, J. S. 2013. Cranial morphology of Recumbirostrans (Lepospondyli) from the Permian of Kansas and Nebraska, and early morphological evolution inferred by micro-computed tomography. Journal of Vertebrate Paleontology 33, 540–552.Google Scholar
Jarvik, E. 1954. On the visceral skeleton in Eusthenopteron with a discussion of the parasphenoid and palatoquadrate in fishes. Kungliga Svenska Vetenskapsakademiens Handlingar 5, 1–104.Google Scholar
Jarvik, E. 1972. Middle and Upper Devonian porolepiformes from East Greenland with special reference to Glyptolepis groenlandica n. sp. Meddeleser Om Gronland 187(2), 1–307+35 pls.Google Scholar
Jarvik, E. 1980. Basic structure and evolution of vertebrates. Vol. 1. 575 pp. London: Academic Press.Google Scholar
Jarvik, E. 1996. The Devonian tetrapod Ichthyostega. Fossils and Strata series 40. Oslo: Scandinavian University Press.Google Scholar
Kimmel, C. B., Sidlauskas, B. & Clack, J. A. 2009. Linked morphological changes during palate evolution in early tetrapods. Journal of Anatomy 215, 91–109.Google Scholar
Lombard, R. E. & Bolt, J. R. 1995. A new primitive tetrapod, Whatcheeria deltae, from the Lower Carboniferous of Iowa. Palaeontology 38, 471–491.Google Scholar
Lombard, R. E. & Bolt, J. R. 2006. The mandible of Whatcheeria deltae, an early tetrapod from the Late Mississippian of Iowa. In Carrano, M. T., Gaudin, T. J., Blob, R. W. & Wi, J. R. (eds) Perspectives on the evolution of mammals, birds, and reptiles, 21–52. Chicago: University of Chicago Press.Google Scholar
Maddin, H. C. & Anderson, J. S. 2012. Evolution of the amphibian ear with implications for lissamphibian phylogeny: insight gained from the caecilian inner ear. Fieldiana Life and Earth Sciences 5, 59–76.Google Scholar
Panchen, A. L. 1972. The skull and skeleton of Eogyrinus attheyi Watson (Amphibia: Labyrinthodontia). Philosophical Transactions of the Royal Society of London, B 263, 279–326.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. Series B, Biological Sciences 309, 505–568.Google Scholar
Pardo, J. D., Szostakiwskyj, M., Ahlberg, P. E. & Anderson, J. S. 2017. Hidden morphological diversity among early tetrapods. Nature 546, 642–645.Google Scholar
Robinson, J., Ahlberg, P. E. & Koentges, G. 2005. The braincase and middle ear region of Dendrerpeton acadianum (Tetrapoda: Temnospondyli). Zoological Journal of the Linnean Society 143, 577–597.Google Scholar
Romer, A. S. & Witter, R. V. 1942. Edops, a primitive rhachitomous amphibian from the Texas red beds. Journal of Geology 50, 925–960.Google Scholar
Sawin, H. J. 1941. The cranial anatomy of Eryops megacephalas. Bulletin of the Museum of Comparative Zoology, Harvard 88, 407–463.Google Scholar
Sigurdsen, T. & Green, D. M. 2011. The origin of modern amphibians: a re-evaluation. Zoological Journal of the Linnean Society 162, 457–469.Google Scholar
Smithson, T. R. 1982. The cranial morphology of Greererpeton burkemorani Romer (Amphibia: Temnospondyli). Zoological Journal of the Linnean Society 76, 29–90.Google Scholar
Snyder, D. 2006. A study of the fossil vertebrate fauna from the Jasper Hiemstra quarry, Delta, Iowa, and its environment. PhD Thesis, University of Iowa, IA, USA. 180 pp.Google Scholar
Warren, A. 2007. New data on Ossinodus pueri, a stem tetrapod from the Early Carboniferous of Australia. Journal of Vertebrate Paleontology 27, 850–862.Google Scholar
Witzke, B. J., McKay, R. M., Bunker, B. J. & Woodson, F. J. 1990. Stratigraphy and paleoenvironments of Mississippian strata in Keokuk and Washington Counties, southeast Iowa. Guidebook Series 10, 1–105. Iowa City: Iowa Department of Natural Resources.Google Scholar
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