I NOTICE: Return or renew all Library Materials! The Minimum Fee tor each Lost Book is $50.00. The person charging this material is responsible for its return to the library from which it was withdrawn on or before the Latest Date stamped below. Thett, mutilation, and ot underlining books are reasons for discipli- nary action and result in may dismissal from the University. To renew call Telephone Center, 333-8400 UNIVERSITY OF ILLINOIS LIBRARY AT URBANA-CHAMPAIGN novo saw LI6I—O-I096 ILLINOIS LI Y ST JRBAN/\- PAIGN AUG 1 3 tPPR 550-O FlELDlANA Geology NEW SERIES, NO. 28 Osteology of Simosaurus gaillardoti and the Relationships of Stem-Group Sauropterygia Olivier Rieppel December 30, 1994 Publication 1462 PUBLISHED BY FIELD MUSEUM OF NATURAL HISTORY Information for Contributors to Fieldiana and research General: Fieldiana is primarily a journal for Field Museum staff members associates, although manuscripts from nonaffiliated authors may be considered as space permits. of at least of The Journal carries a page charge of $65.00 per printed page or fraction thereof. Payment 50% page which reduces the time. Contributions from staff, research charges qualifies a paper for expedited processing, publication to the full associates, and invited authors will be considered for publication regardless of ability pay page charges, however, of the text title charge is mandatory for nonaffiliated authors of unsolicited manuscripts. Three complete copies (including should be submitted two review which be page and abstract) and of the illustrations (one original copy plus copies may or submitted to reviewers before all materials are machine-copies). No manuscripts will be considered for publication complete and in the hands of the Scientific Editor. of Natural Illinois Manuscripts should be submitted to Scientific Editor, Fieldiana, Field Museum History, Chicago, 60605-2496, USA. 11-inch with wide Text: Manuscripts must be typewritten double-spaced on standard-weight, 8Vfe- by paper margins submit text on 5V4-inch diskette on all four sides. If typed on an IBM-compatible computer using MS-DOS, also Microsoft or (WordPerfect 4.1, 4.2, or 5.0, MultiMate, Displaywrite 2, 3 & 4, Wang PC, Samna, Word, Volkswriter, WordStar programs or ASCII). a Table of a "List of For papers over 100 manuscript pages, authors are requested to submit Contents," Illustrations," an "Abstract" and and a "List of Tables" immediately following title page. In most cases, the text should be preceded by Cited." should conclude with "Acknowledgments" (if any) and "Literature format All measurements should be in the metric system (periods are not used after abbreviated measurements). The that issues of Fieldiana. and style of headings should follow of recent The of For more detailed style information, see The Chicago Manual of Style (13th ed.), published by University Chicago Press, and also recent issues of Fieldiana. are desirable References: In "Literature Cited," book and journal titles should be given in full. Where abbreviations authors should follow Botanico-Periodicum-Huntianum and TL-2 Taxonomic (e.g., in citation of synonymies), consistently Sources the Biosis Data Base Literature by F. A. Stafleu & R. S. Cowan (1976 et seq.) (botanical papers) or Serial for (1983) of botanical authors should follow the "Draft Index of Author published by the BioSciences Information Service. Names Abbreviations, Royal Botanic Gardens, Kew," 1984 edition, or TL-2. References should be typed in the following form: 943 Croat, T. B. 1978. Flora of Barro Colorado Island. Stanford University Press, Stanford, Calif., pp. 1963. of montane and lowland rain forest in Ecuador. Grubb, P. J., J. R. Lloyd, and T D. Pennington. A comparison 51: 567-601. I. The forest structure, physiognomy, and fioristics. Journal of Ecology, D. R. A. Langdon, E. J. M. 1979. Yage among the Siona: Cultural patterns in visions, pp. 63-80. In Browman, L.,and The Netherlands. Schwarz, eds., Spirits, Shamans, and Stars. Mouton Publishers, Hague, of South American Murra, J. 1946. The historic tribes of Ecuador, pp. 785-821. In Steward, J. H., ed., Handbook Smithsonian Indians. Vol. 2, The Andean Civilizations. Bulletin 143, Bureau of American Ethnology, Institution, Washington, D.C. Fieldiana: 6: 1-522. Stolze, R. G. 1981. Ferns and fern allies of Guatemala. Part II. Polypodiaceae. Botany, n.s., must be Illustrations: Illustrations are referred to as "figures" in the text (not as "plates"). Figures accompanied by such as "x are not some indication of scale, normally a reference bar. Statements in figure captions alone, 0.8," acceptable. of Fieldiana for details of Captions should be typed double-spaced and consecutively. See recent issues style. All illustrations should be marked on the reverse with author's name, figure number(s), and "top." x 28 and not exceed 1VA x 16V* Figures as submitted should, whenever practicable, be SY2 x 11 inches (22 cm), may to be obtained in the work. This inches (30 x 42 cm). Illustrations should be mounted on boards in the arrangement printed as and ink be original set should be suitable for transmission to the printer follows: Pen drawings may originals (preferred) and must be or photostats; shaded drawings must be originals, but within the size limitation; photostats high-quality, glossy, to author unless otherwise black-and-white prints. Original illustrations will be returned the corresponding upon publication specified. or color must make Authors who wish to publish figures that require costly special paper reproduction prior arrangements with the Scientific Editor. author will receive a Page Proofs: Fieldiana employs a two-step correction system. The corresponding normally copy and answered. one set of of the edited manuscript on which deletions, additions, and changes can be made queries Only of in page proofs will be sent. All desired corrections of type must be made on the single set page proofs. Changes page in can be made if the proofs (as opposed to corrections) are very expensive. Author-generated changes page proofs only author agrees in advance to pay for them. THIS PUBLICATION IS PRINTED ON ACID-FREE PAPER. fiKfc06YUBRABY FIELDIANA Geology NEW SERIES, NO. 28 Osteology of Simosaurus gaillardoti and the Relationships of Stem-Group Sauropterygia Olivier Rieppel Department of Geology Field Museum of Natural History Roosevelt Road at Lake Shore Drive Chicago, Illinois 60605-2496 U.S.A. Accepted July 19, 1994 Published December 30, 1994 Publication 1462 PUBLISHED BY FIELD MUSEUM OF NATURAL HISTORY © 1 994 Field Museum of Natural History Library of Congress Catalog Card Number: 94-61792 ISSN 0096-2651 PRINTED IN THE UNITED STATES OF AMERICA Table of Contents 11. Lower jaw of Simosaurus gaillardoti ... 15 12. Posterior part of the lower jaw of Notho- saurus mirabilis 16 Abstract 1 13. Cervical vertebra of Simosaurus gaillar- zusammenfassung 1 doti 17 Introduction 1 14. Dorsal vertebrae of Simosaurus gaillar- Systematic Paleontology 4 doti 18 slmosaurus gaillardoti h.v. meyer, 1 842 . 4 15. Sacral vertebrae of Simosaurus gaillar- Morphological Description 10 doti 18 Skull 10 16. Dorsal centrum of Simosaurus gaillar- Lower Jaw 14 doti and Nothosaurus 19 Postcranial Skeleton 16 17. Sacral vertebrae of Simosaurus gaillar- Vertebral Column 16 doti 19 Ribs 20 18. Cervical ribs of Simosaurus gaillardoti ... 20 Pectoral Girdle 22 19. Cervical ribs of Nothosaurus 20 Pelvic Girdle 23 20. Ribs of Simosaurus gaillardoti 21 Forelimb 25 21. Sacral ribs of Simosaurus gaillardoti ... 22 Hindlimb 27 22. Caudal ribs of Simosaurus gaillardoti . 22 Functional Morphological Correlates 23. Gastral rib of Nothosaurus 23 in the Skeleton of Simosaurus gail- 24. Pectoral girdle of Simosaurus gaillar- LARDOTl 30 doti 23 Phylogenetic Analysis 36 25. Dermal pectoral girdle of Simosaurus Definition of Characters 37 gaillardoti 24 Summary and Conclusions 73 26. Endochondral pectoral girdle of Simo- Acknowledgments 76 saurus gaillardoti 25 Literature Cited 76 27. Left ilium of Simosaurus gaillardoti .... 26 Appendix I 81 28. Pelvic girdle of Simosaurus gaillardoti ... 27 Appendix II 82 29. Pubis of Nothosaurus sp 28 30. Forelimb of Simosaurus gaillardoti .... 29 31. Intermedium and astragalus of Simo- saurus gaillardoti 31 32. Metacarpal series of Simosaurus gaillar- List of Illustrations doti 31 33. Hindlimb of Simosaurus gaillardoti .... 32 34. Astragalus of Simosaurus gaillardoti ... 33 1. Competing hypotheses of sauropterygian 35. Metatarsal series of Simosaurus gaillar- interrelationships 3 doti 33 2. Distribution of outcrops yielding Simo- 36. Reconstruction of the skeleton of Simo- saurus gaillardoti in the upper Muschel- saurus gaillardoti 34 kalk basin 6 37. Dual jaw adductor system of Simosau- 3. Mandibular symphysis of Simosaurus rus 35 gaillardoti, Nothosaurus mougeoti, and 38. Skull of Pistosaurus longaevus 38 Nothosaurus mirabilis 7 39. Incomplete skull of Cymatosaurus 40 4. Holotype of Simosaurus guilielmi 8 40. Parietal skull table of cf. Cymatosaurus . 40 5. Sutures identified on holotype of Simo- 41. Skull fragment of Placodus gigas 41 saurus guilielmi 9 42. Skull of Nothosaurus mirabilis and Pla- 6. Skull of holotype of Simosaurus guiliel- codus gigas 43 mi var. angusticeps 10 43. Skull of Placodus gigas 45 7. Jaw fragment of cf. Lamprosauroides 44. Mandibular symphysis of Lariosaurus. goepperti 10 Cymatosaurus, and Nothosaurus 46 8. Skull of Simosaurus gaillardoti 11 45. Lower jaw of Placodus gigas 47 9. Skull of Simosaurus gaillardoti in dorsal 46. Mandibular symphysis of Nothosaurus view 12 mirabilis 47 10. Skull of Simosaurus gaillardoti in ven- 47. Dorsal vertebra of a placodont (?Cy- tral view 13 amodus) 49 in 48. Dorsal centrum of Simosaurus, Notho- List of Tables saurus, and Placodus 50 49. Dorsal centrum of a pachypleurosaur and of Pistosaurus 50 1 . Measurements of coracoids of Simosau- 50. Ilium of Nothosaurus and Placodus gi- rus gaillardoti 25 gas 50 2. Measurements of pubis and ischium of 51. Pelvis of Nothosaurus "raabr 50 Simosaurus gaillardoti 30 52. Pectoral girdle of Placodus gigas 51 3. Measurements of the humerus of Simo- 53. Clavicle of Nothosaurus 52 saurus gaillardoti 30 54.