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Fossils and Strata 36 (1994) An international monograph series of palaeontology and �=---ILS stratigraphy ,.........TA Postcranialanatomy and habits of Asian multituberculate mammals ZofiaKielan- Jaworowska andPetr P. Gambaryan SCANDINAVIAN UNI VERSITYPRESS or.l�Oslo · Copenhagen • Stockholm FOSSILS AND STRATA An international monograph series of palaeontology and stratigraphy Owner Lethaia Foundation, Oslo. Administrative Council: Hans Jørgen Hansen, Copenhagen, David Bruton, Oslo, Christina Franzen, Stockholm, Stefan Bengtson, Uppsala. Editor Stefan Bengtson, Institute of Geosciences - Palaeontology, Norbyvagen 22, S-752 36 Uppsala, Sweden; tel. +46-18 18 27 62; fax +46-1818 27 49; Internet [email protected]. Publisher Scandinavian University Press, P.O. Box 2959, Tøyen, N-0608 Oslo 6, Norway. Programme Fossils and Strata is an international series of monographs and memoirs in palaeontology and stratigraphy, published in cooperation between the Scandinavian countries. It is issued in Numbers with individual pagination. Fossils and Strata forms part ofthe same structured publishingprogramme as the journals Lethaia and Boreas. These two journals are fullyinternational and accept papers within their respective sectors of sciencewithout nationallimitations or preferences. Fossils and Strata, however, is an outlet for more comprehensive systematic and regional monographs emanating primarily fromthe five countries of Norden. Contributions from other countries may also be included if this series is deemed appropriate with regard to distribution and availability. Articles can normally only be accepted if they are heavily subsidized by the national Research Council in their country of origin or by other funds. All income is re-invested in fo rthcoming numbers of the series. Althougharticles in German and French may be accepted, the use ofEnglish is stronglypreferred. An English abstract should always be provided, and non-English articles should have English versions of the figurecaptio ns. Abstracts or summaries in one or more additionallanguages may be added. Many regional or systematic descriptions and revisions contain a nucleus ofresults which are of immediate and general interest in international palaeontology and stratigraphy. It is expected that authors of such papers will to some extent duplicate their publication in the fo rm of an article for a journal, in the firstplace Lethaia or Boreas. Sales Individual numbers and standing subscriptions may be ordered from Scandinavian University Press (address as above). Prices (subject to revision) are listed on the back side of each issue. IPA members generally have a 50% discount on older issues (ask for information fromScandina vian University Press). Allprices exclude postage and handling. LETHAlA An international journal of palaeontology and stratigraphy An international journal of Quaternary research Scandinavian University Press, P.O. Box 2959, Tøyen, N-0608 Oslo 6, Norway Postcranial anatomy and habits of Asian multituberculate mammals ZOFIA KIELAN-JAWO ROWSKA AND PETR P. GAMBARYAN Kielan-Jaworowska, Z. & Gambaryan, P.P. 1994 12 15: Postcranial anatomy and habits of Asian multituberculate mammais. Fossils and Strata, No. 36, pp. 1-92. Oslo. ISSN 0300-9491. ISBN 82- 00-37650-8. Postcranial skeietal elements of six Late Cretaceous taeniolabidoid taxa from the GobiDesert are described, and the postcranial musculature of Kryptobaatar and Nemegtbaatar is reconstructed. A new reconstruction of multituberculate pes is given, showing Mt lI! abducted 30° from the longitudinal axis of the tuber calcanei. The calcaneo--MtV contact and abduction-adduction at the astragalonavicular joint in a horizontal plane, around a vertical axis, are recognized as new multituberculate autapomorphies. Other new, partly plesiomorphic, multituberculate characters are: no transverse foramen in atlas; cervical ribs present at least in some taxa; large iliosacral angle (35-37°); iliosacral contact dorsoventral rather than mediolateral; an incipient supraspinous fo ssa and a peg-like acromion. The deep multituberculate pelvis with femoral adductors originating ventraI to the acetabulum and the large mediolateral diameter of the tibia indicate abduction of the fe mora by 30-60°, while twisting of the humerus is indicative of abducted fo relimbs. Long spinous processes of the lumbar vertebrae, sloping craniodorsally in Asian multituberculates, suggest asymmetrical gait and long jumps, but the short tibia and short Mt lI! suggest short jumps. This inconsistency is due to the abducted limbs, because of which the direct transposition of jump mechanics of mammals with parasagittal limbs does not work for multituberculates. Multituber­ culates possibly had a steeper trajectory ofjump than modem therian mammals. The studied Asian multituberculates do not show adaptations to arborealism. It is suggested that the coracostemal joint disappeared in multituberculates (and independently in therians) as an adaptation to asymmetrical gai!. It is speculated that the competitive inferiority of multituberculates to eutheri­ ans is related to the structure of the pelvis with a ventraI keel, which hindered prolongation of the gestation period, and to abducted limbs that limited their endurance for prolonged running. The analysis of multiturbeculate-therian postcranial synapomorphies does not support the idea that Multituberculata is the sister taxon of Theria. DMammalia, Multituberculata, Anatomy, Creta­ ceous, Asia. Zofia Kielan-Jaworowska, Paleontologisk Museum, Universitetet i Oslo, Sars Gate 1, N--0562Oslo 5, Norway; Petr P. Gambaryan, Zoological Institute, Russian Academy of Sciences, Universitetskaya Naberezhnaya 1, 199164 St. Petersburg, Russia; 27th September, 1993; revised 21st April, 1994. Contents Introduction .............................................................................................. 3 Genus Nemegtbaatar Kielan-Jaworowska, 1974 ................................ 17 Terminology ......................................................................................... 5 Nemegtbaatar gobiensis Kielan-Jaworowska, 1974 ............................. 17 Osteological descriptions .......................................................................... 6 Skull ............................................................................................... 17 Suborder Cimolodonta McKenna, 1975 (new rank); Infraorder Axial skeleton .............................................................. .................. 17 Taeniolabidoidea Sloan & Van Valen, 1965 (new rank); Pectoral girdle and forelimb ............................. ...... ......... ........... 22 Family Eucosmodontidae Jepsen, 1940 ...................................... 6 Pelvis and hind limb ...................................................................... 26 Genus KryptobaatarKielan- Jaworowska, 1970 .................................... 6 Genus Chulsanbaatar Kielan-Jaworowska, 1974 ............................... 30 Kryptobaatardashzevegi Kielan-Jaworowska, 1970 ............................. 6 Chulsanbaatar vulgaris Kielan-J aworowska, 1974 ............................. 30 Skull ................. ................................................................................ 6 Skull ............................................................................................... 31 Axial skeleton ........ ......................... ...................................... ... ...... .. 6 Hyoid apparatus ................. ........................................................... 31 Pectoral girdle (forelimb unknown) ............................................... 7 Axial skeleton ..................... ........................................................... 32 Pelvic girdle and hind limb ............................................................. 7 Pectoral girdle and forelimb ......................................................... 36 Pelvic girdle and hind Iimb ..................... .... ...... ..... ....................... 36 Anatomical comparisons ........................................................................ 57 Family Sloanbaataridae Kielan-Jaworowska, 1974 ............................ 38 Proportions of the body ..................................................................... 57 Genus Sloanbaatar Kielan-Jaworowska, 1970 .................................... 38 Hyoid apparatus ................................................................................. 57 Sloanbaatar mirabilis Kielan-Jaworowska, 1970 ................................ 38 Vertebral column ............................................................................... 57 Axial skeleton ................................................................................ 38 Pectoral girdle and fo relimb .............................................................. 60 Pelvie girdle and hind limb ........................................................... 38 Pelvie girdle and hind limb ................................................................ 62 Family Taeniolabididae Granger & Simpson, 1929 ........................... 39 Functional anatomy ................................................................................ 65 Genus Catopsbaatar Kielan-Jaworowska, 1994 .................................. 39 Reconstruction oflocomotion .......................................................... 65 Catopsbaatar catopsaloides (Kielan-Jaworowska, 1974) ..................... 39 Structure and function of multituberculate pes ................................. 74 Taeniolabidoid, fa
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