Two new papers

["高橋 和男" <pantheon@dino-pantheon.com>]

Enantiornithine Bird with Diapsidian Skull and Its Dental Development
in the Early Cretaceous in Liaoning, China
GONG Enpu, HOU Lianhai and WANG Lixia
ACTA GEOLOGICA SINICA Vol.78 No.1 pp.1-7

Abstract
A large number of enantiornithine birds are discovered from the Early
Cretaceous Jiufutang Formation in western Liaoning, China. They are all
small-sized birds with a few small teeth. The enantiornithine bird from
the Jiufutang Formation in the Shangheshou area, Chaohang, Liaoning 
Province reported in this paper is the largest individual known in all
enantiornithine birds of the Early Cretaceous. However, its teeth 
possess a feature of pseudoheterodont. Some diffrerent development
stages of the new teeth substitute the earlier stages and stages of
development are preserved in this specimen. This development pattern is
similar to that of Archaeopteryx and alligator but not dinosaur. A 
well-developed postorbital was also preserved in the skull, which was
a diapsidian skull like that of Confusiusornis. Additionally, the 
distinctive preservation of its prefrontal distinguishes it from other
enantioruthine birds of the Early Cretaceous.

Aberratiodontuiformes ord. nov.
Aberratiodontuidae fam. nov.
Aberrtiodontus wui gen. et sp. nov.


A New Troodontid (Theropoda: Troodontidae) from the Lower Cretaceous
Yixian Formation of Western Liaoning, China
XU Xing and WAN Xiaolin
ACTA GEOLOGECA SINICA Vol.78 No.1 pp.22-26

Abstract
A specimen collected from the Lower Cretaceous Yixian Formation of 
western Liaoning, China, represents a new genus and species of 
troodontid theropod. The new taxon is named and described on the basis
of the holotype and the only known specimen, which comprises an
articulated skelton with the presacral vertebral, shoulder girdle and
forelimbs missing as preserved. Diagnostic features of the new species
include nasals that are sinusoid in lateral view, absence of a passage
connecting the antorbital and maxillary fenestrae, relatively large
teeth, plate-like chevrons forming a band along most of the length of
the tail, and a long neck between the femoral head and shaft. The 
temporal constraints of the three paravian groups (Troodontidae, 
Doromaeosauridae and Aves) combined with the character distributions 
among the earliest known troodontids indicate a rapid evolution at the
base of the Troodontidae.

Sinusonasus magnodens gen. et sp. nov.



--
TAKAHASHI, Kazuo 高橋　和男
pantheon@dino-pantheon.com
http://www.dino-pantheon.com/
--