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Naturwissenschaften

, Volume 95, Issue 7, pp 663–669 | Cite as

An Upper Cretaceous lizard with a lower temporal arcade

  • Jun-chang Lü
  • Shu-an Ji
  • Zhi-ming Dong
  • Xiao-chun WuEmail author
Short Communication

Abstract

The reduced lower temporal arcade of the skull and the movable quadrate are the most distinctive features of squamates. Up to now, no exception has been documented for any fossil or extant squamates. We report here a new fossil lizard that possesses a complete lower temporal arcade and an unmovable quadrate. The anatomical relationships indicate that those two modifications were secondarily obtained in the new lizard. The complete lower temporal bar and the firm contact between the pterygoid and quadrate may have served as a brace to support the quadrate jaw articulation and thus prevent it from twisting anteriorly rather than posteriorly during the bite cycles. This represents an entirely new pattern of jaw muscle functions within the Squamata.

Keywords

Squamate Lizard Upper Cretaceous Henan China 

Notes

Acknowledgments

We thank the Ministry of Science and Technology of China (973-Project-2006CB701405) and the Bureau of Land and Resources of Henan Province, China for supporting the project. We are greatly indebted to the Shandong Tianyu Natural Museum at Pingyian, Shandong Province, China for allowing us to study the specimen. Mr. Gui-hai Cui skillfully prepared the specimen. Dr. Peter Dodson (Philadelphia) read the earlier draft, offering helpful advises and suggestions. The functional discussion of the manuscript is benefited from the comments and suggestions of the four reviewers. X-c Wu thanks Dr. Hai-lu You for providing access to his office when working on the specimen and the Institute of Geology, Chinese Academy of Geological Sciences for support during his stay in the institute. The revision of the manuscript was done in National Museum of Natural Sciences, Republic of China during X-c Wu’s sabbatical stay.

References

  1. Bureau of Geology and Mineral Resources of Henan Province (1989) Regional geology of Henan Province [M]. Geological Publication House, BeijingGoogle Scholar
  2. Carroll RL (1985) A pleurosaur from the Lower Jurassic and the taxonomic position of the Sphenodontida. Palaeontogr Abt A 189:1–28Google Scholar
  3. Carrol RL (1988) Late Paleozoic and early Mesozoic lepidosauromorphs and their relation to lizard ancestry. In: Estes R, Pregill G (eds) Phylogenetic relationships of the lizard families. Stanford University Press, Stanford, pp 99–118Google Scholar
  4. Cong L-Y, He L-H, Wu X-C, He J-F (1988) The gross anatomy of Alligator sinensis Fauvel. Science Press, BeijingGoogle Scholar
  5. De Vree E, Gans C (1987) Kinetic movements in the skull of adult Trachydosaurus rugosus. Anat Hist Embryol 16:206–209Google Scholar
  6. Estes R (1983) Sauria terrestria, Amphisbaenia. Handbuch der Paläoherpetologie, part 10A. Gustav Fischer, StuttgartGoogle Scholar
  7. Estes R, de Queiroz K, Gauthier J (1988) Phylogenetic relationships within Squamata. In: Estes R, Pregill G (eds) Phylogenetic relationships of the lizard families. Stanford University Press, Stanford, pp 119–281Google Scholar
  8. Frazzetta TH (1962) A functional consideration of cranial kinesis in lizards. J Morph 111:287–320PubMedCrossRefGoogle Scholar
  9. Gauthier J, Estes R, de Queiroz K (1988) A phylogenetic analysis of Lepidosauromorpha. In: Estes R, Pregill G (eds) Phylogenetic relationships of the lizard families. Stanford University Press, Stanford, pp 15–98Google Scholar
  10. Gorniak GC, Rosenberg HI, Gans C (1982) Mastication in the tuatara Sphenodon punctatus (Reptilia: Rhynchocephalia): structure and activity of the motor system. J Morph 171:321–353CrossRefGoogle Scholar
  11. Haas G (1973) Muscles of the jaws and associated structures in the Rhynchocephalia and Squamata. In: Gans C (ed) Biology of the Reptilia 4. Academic, London, pp 285–483Google Scholar
  12. Herrel A, De Vree F (1999) Kinematics of intraoral transport and swallowing in the herbivorous lizard Uromastix acanthinurus. J Exp Biol 202(9):1127–1137PubMedGoogle Scholar
  13. Herrel A, Aerts P, De Vree F (1998) Static biting in lizards: functional morphology of the temporal ligaments. J Zool Lond 244:135–143CrossRefGoogle Scholar
  14. Herrel A, De Vree F, Delheusy V, Gans C (1999) Cranial kinesis in gekkonid lizards. J Exp Biol 202:3687–3698PubMedGoogle Scholar
  15. Iordansky NN (1996) The temporal ligaments and their bearing on cranial kinesis in lizards. J Zool Lond 239:167–175Google Scholar
  16. Metzger K (2002) Cranial kinesis in Lepidosaurs: skull in motion. In: Aerts P, D’Août K, Herrel A, Van Damme R (eds) Topics in functional and ecological vertebrate morphology. Shaker Publishing, Herzogenrath, pp 15–46Google Scholar
  17. Oelrich TM (1956) The anatomy of the head of Ctenosaura pectinata (Iguanidae). Miscell Publ Mus Zool Univ Michigan 94:1–122Google Scholar
  18. Rieppel O (1978) Streptostyly and muscle function in lizards. Experientia 34:776–777CrossRefGoogle Scholar
  19. Rieppel O, Gronowski RW (1981) The loss of the lower temporal arcade in diapsid reptiles. Zool J Linn Soc 72:203–217CrossRefGoogle Scholar
  20. Schumacher GH (1973) The head muscles and hyolaryngeal skeleton of turtles and crocodilians. In: Gans C (ed) Biology of the Reptilia 4. Academic, London, pp 101–194<!–-[AU2] Reference list | Schumacher 1973 is not cited in the text. Kindly provide citation for this referenceGoogle Scholar
  21. Smith K (1980) Mechanical significance of streptostyly in lizards. Nature 283:778–779CrossRefGoogle Scholar
  22. Smith K (1982) An electromyographic study of the function of the jaw adducting muscles in Varanus exanthematicus (Varanidae). J Morph 173:137–158CrossRefGoogle Scholar
  23. Throckmorton GS (1976) Oral food processing in two herbivorous lizards, Iguana iguana and Uromastyx aegyptius. J Morph 148:363–390PubMedCrossRefGoogle Scholar
  24. Throckmorton GS (1980) The chewing cycles in the herbivorous lizard Uromastyx aegyptius (Agamidae). Archives Oral Biol 25:225–233CrossRefGoogle Scholar
  25. Whiteside DI (1986) The head skeleton of the Rhaetian sphenodontid Diphydiontosaurus avonis gen. et sp. nov., and the modernizing of a living fossil. Phil Trans Roy Soc London Ser B 132:379–430CrossRefGoogle Scholar
  26. Wu X-C (1994) Late Triassic–Early Jurassic sphenodontians from China and the phylogeny of the Sphenodontia. In: Fraser NC, Sues H-D (eds) In the shadow of the dinosaur: early Mesozoic tetrapods. Cambridge University Press, Cambridge, pp 38–69Google Scholar
  27. Wu X-C (2003) Functional morphology of the temporal region in the Rhynchocephalia. Can J Earth Sci 40:589–607CrossRefGoogle Scholar

Copyright information

© Springer-Verlag 2008

Authors and Affiliations

  • Jun-chang Lü
    • 1
  • Shu-an Ji
    • 1
  • Zhi-ming Dong
    • 2
  • Xiao-chun Wu
    • 3
    Email author
  1. 1.Geological InstituteChinese Academy of Geological SciencesBeijingPeople’s Republic of China
  2. 2.Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of SciencesBeijingPeople’s Republic of China
  3. 3.Earth ScienceCanadian Museum of NatureOttawaCanada

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