Hostname: page-component-cd9895bd7-lnqnp Total loading time: 0 Render date: 2024-12-28T02:32:52.809Z Has data issue: false hasContentIssue false

Functional morphology of the skull in Lysorophus: a snake-like Paleozoic amphibian (Lepospondyli)

Published online by Cambridge University Press:  25 May 2016

John R. Bolt
Affiliation:
Dept. Geology, Field Mus. Nat. Hist.; Roosevelt Rd. and S. Lake Shore Drive, Chicago, Illinois 60605
Richard J. Wassersug
Affiliation:
Dept. Anatomy, Univ. Chicago; Chicago, Illinois 60637

Abstract

Lysorophus, a serpentiform, nearly limbless, aquatic Paleozoic amphibian was described in detail by Sollas in 1920. Although Sollas did not discuss cranial kinesis, his original reconstructions suggest that Lysorophus had an unusually kinetic skull for an amphibian. We have reexamined the skull of Lysorophus and find that kinesis, if present, was slight. The maxillae, premaxillae, and vomers might have moved in limited protraction and retraction, with the premaxillae rotating about their contacts with the nasals. There is a possibility of small medio-lateral movements of the lacrimal and maxilla as a unit at the lacrimal-prefrontal joint. The skull of Lysorophus shows many features convergent with the skulls of burrowing reptiles, such as amphisbaenians. Modifications in the skull of Lysorophus from a more primitive tetrapod condition seem associated with burrowng in a soft substratum rather than with kinesis per se.

Type
Research Article
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

Literature Cited

Bellairs, A. d'A. 1950. Observations on the cranial anatomy of Anniella, and a comparison with that of other burrowing lizards. Zool. Soc. Lond. Proc. 119:887904.Google Scholar
Bolt, J. R. 1974. Evolution and functional interpretation of some suture patterns in Paleozoic labyrinthodont amphibians and other lower tetrapods. J. Paleontol. 48:434458.Google Scholar
Boltt, R. E., and Ewer, R. F. 1964. The functional anatomy of the head of the puff adder, Bitis arietans (Merr.). J. Morphol. 114:83106.Google Scholar
Broili, F. 1908. Systematische und biologische Bemerkungen zu den permischen Gattung Lysorophus. Anat. Anz. 33:290298.Google Scholar
Brough, M. C., and Brough, J. 1967. Studies on early tetrapods, I. The Lower Carboniferous microsaurs. R. Soc. Lond., Phil. Trans., B. 252:107129.Google Scholar
Carroll, R. L., and Baird, D. 1968. The Carboniferous amphibian Tuditanus (Eosauravus) and the distinction between microsaurs and reptiles. Am. Mus. Nat. Hist., Novit. 2337:150.Google Scholar
Gans, C. 1960. Studies on amphisbaenids (Amphisbaenia, Reptilia), I. A taxonomic revision of the Trogonophinae, and a functional interpretation of the amphisbaenid adaptive pattern. Am. Mus. Nat. Hist., Bull. 119:131204.Google Scholar
Gans, C. 1974. Biomechanics: an Approach to Vertebrate Biology. 261 pp. J. B. Lippincott Co.; Philadelphia, Pa.Google Scholar
Haas, G. 1973. Muscles of the jaws and associated structures in the Rhyncocephalia and Squamata. pp. 285490. In: Gans, C. and Parsons, T., eds. Biology of the Reptilia, vol. 4., Morphology D. Academic Press; New York, N.Y.Google Scholar
Herring, S. W. 1972. Sutures—a tool in functional cranial analysis. Acta Anat. 83:222247.Google Scholar
Lakjer, T. 1926. Studien uber die Trigeminusversorgte Kaumuskulatur der Sauropsiden. 155 pp. C. A. Teitzel; Copenhagen.Google Scholar
Moss, M. L. 1957. Experimental alteration of sutural area morphology. Anat. Rec. 127:569589.Google Scholar
Olson, E. C. 1956. Fauna of the Vale and Choza: 11. Lysorophus: Vale and Choza. Diplocaulus, Cacops, and Eryopidae: Choza. Fieldiana Geol. 10:313322.Google Scholar
Olson, E. C. 1971. A skeleton of Lysorophus tricarinatus (Amphibia: Lepospondyli) from the Hennessey Formation (Permian) of Oklahoma. J. Paleontol. 45:443449.Google Scholar
Olson, E. C., and Bolles, K. 1975. Permo-carboniferous fresh water burrows. Fieldiana Geol. 33:in press.Google Scholar
Panchen, A. L. 1964. The cranial anatomy of two coal measure anthracosaurs. R. Soc. Lond., Phil. Trans, B. 247:593637.Google Scholar
Panchen, A. L. 1970. Teil 5A: Anthracosauria. In: Kuhn, O., ed. Handbuch der Paläoherpetologie. 84 pp. Gustav Fischer Verlag; Stuttgart.Google Scholar
Panchen, A. L. 1972. The interrelationships of the earliest tetrapods. In: Joysey, K. A. and Kemp, T. S., eds. Studies in Vertebrate Evolution. 284 pp. Winchester Press; N.Y.Google Scholar
Romer, A. S. 1956. Osteology of the Reptiles. 772 pp. Univ. of Chicago Press; Chicago, Ill.Google Scholar
Romer, A. S. 1966. Vertebrate Paleontology. 3rd ed.468 pp. Univ. of Chicago Press; Chicago, Ill.Google Scholar
Smalian, C. 1885. Beiträge zur Anatomie der Amphisbaeniden. Z. Wiss. Zool. 42:126202.Google Scholar
Sollas, W. J. 1920. On the structure of Lysorophus, as exposed by serial sections. R. Soc. Lond., Phil. Trans., B. 209:481526.Google Scholar
Zangerl, R. 1944. Contributions to the osteology of the skull of the Amphisbaenidae. Am. Midl. Nat. 31:417454.Google Scholar