Iguanodon(?) sp. and Jixiangornis

["Nick Gardner" <ratites637@hotmail.com>]

Neraudeau et al., 2003.  A new Early-Cenomanian paralic deposit with fossil 
wood, amber with insects and Iguanodontidae (Dinosauria, Ornithopoda) at 
Fouras (Charente-Maritime, southwestern France).  C.R. Palevol: 221-230

I used Babel Fish to translate the part of the paper describing Iguanodon(?) 
sp. so I'm little fuzzy on some details.  Instead of trying to re-describe 
the entire thing, I'm copying my translation into this email.

"The remainders of dinosaurs are represented in the layer of Fouras by about 
fifty osseous fragments, including only one about fifteen decimeteres. 
Except for a right ulna (Figs. 2.1A and B) and distal end of a tibia (Figs. 
2.C and D), these fragments are not for the majority, identifiable with 
precision.

The preserved ulna is a 25.5 cm long bone. In lateral view, its posterior 
margin is right[?] and not concave, as in Iguanodon bernissartensis [ 25 ], 
Iguanodon atherfieldensis [ 26 ] or Ouranosaurus nigeriensis [ 30 ]. The 
proximal end is widened and has an olecranon process more developed than 
that of Hadrosauridae. A concavity intended to receive the humerus is 
arranged on the former face of the olecranon process. Ventral to this 
concavity, a vertical and prominent osseous peak extends distally for ten 
centimeters. This peak longitudinally divides the anteroproximal face of the 
ulna into two concavities. Side concavity thus formed is intended for the 
articulation with the radius. The section of the proximal end has a form of 
T at the specimen of Fouras, whereas it is U-shaped in Ouranosaurus [ 30 ]. 
In Iguanodon atherfieldensis, the longitudinal peak develops proximmally on 
the anteromedial face of the ulna, then extends distally by dividing the 
former face from the ulna [ 26 ].  The width of the ulna decreases gradually 
in front of the proximal end of the ulna, to grow again with the approach of 
the distal end. The distal end is slightly compressed transversely. It 
anteromedially presents a light depression of which was to form part the 
distal end of the radius. Contrary to Ouranosaurus [ 30 ], the distal end is 
not curved backwards.

The distal end of the right tibia of the specimen of Fouras is lengthened 
transversely. The malleoli are strongly damaged, but the external malleolus 
extends distally, definitely further the internal malleolus. The two 
malleoli are separated by a marked projection. The former face of the distal 
end is plane, and its strongly convex posterior face as in Camptosaurus 
prestwichii [ 10(fig. 10-L) ]. This character makes it possible to 
distinguish the distal extremity from Fouras of those of Iguanodon 
atherfieldensis and Iguanodon bernissartensis, at which the former and 
posterior faces of the distal end of the tibia are concave [ 25, 26 ].

If the two bones described previously are clearly identifiable like 
pertaining to Iguanodontidae, their attribution with the genus Iguanodon 
remains dubious. The remainders of Iguanodontidae are largely represented in 
the European layers of the lower Cretaceous, and two species, Iguanodon 
bernissartensis [ 3 ] and Iguanodon atherfieldensis [ 14 ], were described 
in detail [ 25, 26 ].  The genus Rhabdodon [ 17 ], is only Iguanodontidae 
known in the higher Cretaceous (Campanien and Maastrichtien) of Western 
Europe. Although it is present in many European layers [ 1, 4, 11, 15, 27 ], 
its membership of Iguanodontidae only was recently suggested [ 29 ].  The 
discovery of new remainders of Iguanodontidae in lower Cénomanien of the 
layer of Fouras brings to us significant data from a point of view 
biostratigraphic. If the membership of the Iguanodon kind can be confirmed 
by new discoveries, it will extend the stratigraphic distribution of this 
genus to the higher Cretaceous.  This discovery stresses also the importance 
of the layer of Fouras: the vertebrate remainders continental ones in 
general, and dinosaurs in particular, are indeed very rare in France for the 
period extending from Cénomanien in Santonien [ 6 ]."

-------------------------------------------------------------

Ji Qiang, Ji Shuan, Zhang Hongbin, You Hailu, Zhang Jianping, Wang Lixia, 
Yuan Changri, & Ji Xinxin, (2002).  A new Avialian Bird - Jixiangornis 
orientalis gen. et sp. nov. - from the Lower Cretaceous of Western Liaoning, 
NE, China.  Journal of Nanjing University (Natural Sciences) 38(6): 723-736

> From the Abstract-
"A well-preserved specimen of an avialian bird with a complete skull and 
postcranial bones was found from the lower part of the Yixian Formation 
(Early Cretaceous) in Sihetun area of Beipiao City, western Liaoning, NE 
China.  It is characterized by the development of a beak, the large sternum 
with a weak keel, the typical U-shaped furcula, the forelimbs much longer 
than the hindlimbs (about 131:100) and the long tail with about 27 caudal 
vertebrae.  Due to the characters mentioned above, the new avialian bird is 
surely capable of flight stronger than Shenzhouraptor and Archaeopteryx.  It 
is described in detail and named as Jixiangornis orientalis gen. et sp. nov. 
in this paper."

Ji et al. assign it to the Avialae (Gauthier, 1986)

Material- premaxilla, nasal, frontal, lacrimal, maxilla, orbit, jugal, 
quadrate, dentary, hyoid, cervical vertebrae, dorsal vertebrae, sacral 
vertebrae, caudal vertebrae, scapula, furcula, sternum, uncinate processes, 
sternal ribs, coracoids, dorsal ribs, gastralia, manus (MC I, MC II, MC III, 
M I-1, M II-1, II-2, III-3, radiale, semilunate carpal, radiale), ulna, 
radius, humerus, ilium, ischium, pubis, femur, tibiotarsus, fibula, 
calcaneum, astragalus, complete pes

The premaxilla is not tapered rostrally.  The maxilla contacts external 
naris. Nasals are rostrodorsally depressed (?). Premaxillary teeth absent 
are absent.  Maxillary teeth are absent.  The antorbital fenestra has not 
been lost.

The dentary teeth are absent.  The dentary is rostroventrally curved.  The 
external mandibular fenestra is present.  The dentary is ~60-75% of 
mandibular length.  The posteroventral process of the dentary is very long, 
and extends for most of the length of the external mandibular fenestra.

There are quadrangular lateral processes on sternum.  The sternal plates are 
ossified and co-fused with a midline keel.  The furculae is robust and 
U-shaped.  The acromion process of the scapula appears to be prominent, 
triangular, and perhaps cranioventrally directed.  The superficial surfaces 
of coracoid face anteriorly.  There are ossified uncinate processes.

The metacarpals are not fused to each other or to the semilunate carpal.  
The semilunate carpal covers the proximal bases of metacarpals I, II, and 
III.  Metacarpal I is 10% or less the length of metacarpal II.  Metacarpal 
III is bowed posterolaterally.  Manual phalanx I-1 is slightly bowed. Manual 
ungual I is shorter than manual ungual II, and less curved.  Manual 
phalanges II-1 and II-2 are nearly subequal.  Only III-3 and the ungual as 
far as the phalanges go for manual digit III.  Manual phalanx II-1 is 
expanded transversely.  The ulna is longer than the humerus.  The humerus 
appears to have a hatchet-shaped deltopectoral crest.

The astragalus and calcaneum are proximally fused to the tibia, but I 
presume not to each other since they are referred to as separate elements?  
The metatarsus is proximally fused to each other and to the distal tarsals.  
The hallux is retroverted.  Pedal ungual II is larger and more curved than 
III.  Pedal phalanx II-1 is shorter (~75%) than II-2.  Pedal digit IV is 
nearly as long as III and much longer than II.  The distalmost phalanges are 
the longest in all the digits.  I cannot tell if pedal digit II is 
hyperextendible.  The tibia is longer than femur.

The tail is 5-7 times the length of the femur.

Figure 5 is the uhm... quote "sketchy cladogram of dinosaur-bird 
phylogenetic relationship, showing that Shenzhouraptor sinensis Ji et al. 
2002 and Jixiangornis orientalis gen. et sp. nov. from western Liaoning of 
China are the oldest birds with a real ability of active flight in the 
world." Here it is-

-- Avialae
     |-- Archaeopteryx
     `-- Orthavialae
         |-- Shenzhouraptor
         `-- Euavialae
             |-- Jixiangornis
             `-- Pygostylia
                 |-- Confuciusornithidae
                 `--+-- Enantiornithes
                    `-- Ornithurae
                        `-- Aves




~~~~

Nick Gardner

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