A new specimen of Eurylambda aequicrurius and considerations on "symmetrodont" dentition and relationships. American Museum novitates ; no. 3398

Simple item page
dc.contributor.authorRougier, Guillermo W.en_US
dc.contributor.authorSpurlin, Barton K.en_US
dc.contributor.authorKik, Peter K.en_US
dc.contributor.authorMarsh, Othniel Charles, 1831-1899.en_US
dc.date.accessioned2005-10-06T16:39:33Z
dc.date.available2005-10-06T16:39:33Z
dc.date.issued2003en_US
dc.description15 p. : ill. ; 26 cm.en_US
dc.descriptionIncludes bibliographical references (p. 14-15).en_US
dc.description.abstractA new specimen of the tinodontid "symmetrodont" Eurylambda (Simpson, 1925a, 1929) from the late Jurassic Como Bluff Quarry, Morrison Formation, is described. The specimen, a complete upper left molariform, is probably an M1. The major crown cusps of Eurylambda show similarities to those of triconodontids on the one hand and to spalacotherioids on the other. Cusp B of basal mammaliaforms is tentatively proposed as homologous with the cusp traditionally described as a stylocone in Eurylambda and with cusp Bʹ of Peralestes. These homologies imply that the stylocone is ancestrally a small cusp in the lineage leading to Theria and that the development of a parastylar lobe or "hook" is a derived feature of post-tinodontid mammals. If accepted, this scenario results in a more complex origin for the therian upper molar than previously recognized. Wear facet 1 (Crompton, 1971) of holotherians would not be homologous between Kuehneotherium-Eurylambda-Zhangheotherium, on the one hand, and the therians, on the other.en_US
dc.format.extent450544 bytes
dc.format.mimetypeapplication/pdf
dc.identifier.urihttp://hdl.handle.net/2246/2824
dc.languageengen_US
dc.language.isoen_US
dc.publisherNew York, NY : American Museum of Natural Historyen_US
dc.relation.ispartofseriesAmerican Museum novitates ; no. 3398en_US
dc.subject.lccQL1 .A436 no.3398, 2003en_US
dc.subject.lcshEurylambda aequicrurius.en_US
dc.subject.lcshTeeth, Fossil -- Wyoming -- Como Bluff.en_US
dc.subject.lcshMolars -- Evolution.en_US
dc.subject.lcshMaxilla.en_US
dc.subject.lcshMammals, Fossil -- Wyoming -- Como Bluff.en_US
dc.subject.lcshTeeth -- Evolution.en_US
dc.subject.lcshMammals -- Evolution.en_US
dc.subject.lcshDentition.en_US
dc.subject.lcshPaleontology -- Jurassic -- Wyoming -- Como Bluff.en_US
dc.subject.lcshPaleontology -- Wyoming -- Como Bluff.en_US
dc.subject.lcshPaleontology -- Morrison Formation.en_US
dc.titleA new specimen of Eurylambda aequicrurius and considerations on "symmetrodont" dentition and relationships. American Museum novitates ; no. 3398en_US
dc.typetexten_US

Files

Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
/v2/dspace/ingest/pdfSource/nov/N3398.pdf
Size:
439.98 KB
Format:
Adobe Portable Document Format
Description:
Download

Collections

American Museum Novitates