The skull ofMorganucodon
作者:
K. A. KERMACK,
FRANCES MUSSETT,
H. W. RIGNEY,
期刊:
Zoological Journal of the Linnean Society
(WILEY Available online 1981)
卷期:
Volume 71,
issue 1
页码: 1-158
ISSN:0024-4082
年代: 1981
DOI:10.1111/j.1096-3642.1981.tb01127.x
出版商: Blackwell Publishing Ltd
关键词: Morganucodon;Triconodonta;Docodonta;middle ear;jaw articulation;skull;Mesozoic mammal;Atheria;mammal;like reptile;cynodont;braincase;monotreme
数据来源: WILEY
摘要:
Morganucodonis a triconodont (atherian) mammal from the Lower Jurassic. Two species are described:M. oehlerifrom China andM. watsonifrom Wales. The skull inM. walsoniis 26 mm long;M. oehleriis slightly larger. The dentition is differentiated functionally into incisors, canines, premolars and molars. The pineal foramen is closed. The prefrontals, postfrontals and postorbitals are lost. Septomaxilla, quadratojugal, tabular and pterygoid flanges are retained. The bony external nares are unpaired. The nasal cavity had the mammalian complement of turbinals. The posterior palate has ridges and troughs similar to those in tritylodonts, triconodonts and multituberculates. The alisphenoid ascending process is narrow and is not in contact with the anterior lamina of the petrosal, lying lateral to it. There is a cavum epiptericum, as in late therapsids. The anterior lamina forms the lateral braincase wall, perforated by the foramina pseudovale and pseudorotundum. There is a squamosal‐dentary articulation, but the reptilian jaw joint is retained. The ear resembles that in later therapsids, with the tympanum in the lower jaw. The small quadrate was moveable, buttressed medially be a large stapes. Sound conduction from the tympanum was via articular, quadrate and stapes. The systematic position ofMorganucodonis discusse
点击下载:
PDF
(14703KB)
返 回