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RE: AW: The cladogram from the supp. inf. of the *Anchiornis* paper



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Tim williams wrote-

> AFAIK=2C the first paper to formally sink _Shenzhouraptor_ into _Jeholorn=
is_ was Zhou and Zhang (2006):
>
>
> "Two junior synonyms of _Jeholornis prima_ were proposed in the past base=
d on different specimens of _Jeholornis_. One is _Shenzhouraptor_ (Ji et al=
.=2C 2002b)=2C published in the same month (July 2002) as _Jeholornis_=2C b=
ut the Chinese Geological Science Bulletin that published the name is a mon=
thly journal=2C therefore _Jeholornis_=2C which was published in the weekly=
 journal Nature (25 July 2002)=2C according to international nomenclature r=
ule [sic]=2C clearly has the priority."
>
> (The other junior synonym is _Jixiangornis orientalis_: "...but like _She=
nzhouraptor_=2C it possesses no obvious differences from _Jeholoris prima_.=
")
>
>
> Zhou Z.-H. & Zhang F.-C. (2006). Mesozoic birds of China: a synoptic revi=
ew. Vertebrata PalAsiatica 44: 74-98.
>
>
> I don't know if their assertion regarding weekly vs monthly publications =
has a sound basis in the Code. In any case=2C the practice of regarding _Je=
holornis_ as having priority over _Shenzhouraptor_ has been followed fairly=
 consistently in the literature.

It doesn't have a sound basis.  People should be using Shenzhouraptor inste=
ad of Jeholornis (ditto for Scansoriopteryx instead of Epidendrosaurus).  F=
rom my site-
=20
Both Shenzhouraptor and Jeholornis were named in July 2002=2C with Shenzhou=
raptor appearing in the July issue of Geological Bulletin of China=2C and J=
eholornis appearing in the July 25th issue of Nature. I first recognized th=
em as synonymous on the DML=2C which has been the consensus in the literatu=
re as well. Ji et al. (2003) made Jeholornis a junior synonym of Shenzhoura=
ptor without comment=2C incorrectly making the Jeholornis holotype a paraty=
pe of Shenzhouraptor. Zhou and Zhang (2006) on the other hand=2C made Shenz=
houraptor a junior synonym of Jeholornis=2C again without discussion. They =
stated the ICZN gives priority to a weekly journal instead of a monthly jou=
rnal=2C undoubtedly based on Article 21.3.1. Yet=2C that article only appli=
es in the absence of evidence of "the earliest day on which the work is dem=
onstrated to be in existence as a published work." As Olshevsky (DML=2C 200=
2) noted=2C Wang (2002) reported the Shenzhouraptor article was published a=
s early as July 23rd=2C two days before Jeholornis was published. Thus Shen=
zhouraptor has precedence if the genera are synonymous. Somewhat oddly=2C n=
o one has yet published a rationale for their synonymy.

Comparison is hindered by the short description of each taxon and low resol=
ution photos for much of Jeholornis. Shenzhouraptor's holotype was reported=
 to have no observed teeth=2C yet the Jeholornis holotype has three tiny de=
ntary teeth=2C and IVPP V13550 has two. I agree with Chiappe and Dyke (2006=
) that poor preservation in Shenzhouraptor may be to blame=2C as they are h=
ard to discern even in the published photo of Jeholornis. Ji et al. report =
that Shenzhouraptor has a straight mandible=2C and its lower edge does appe=
ar less concave than in Jeholornis and IVPP V13550=2C but this could be due=
 to individual variation. The caudal vertebral count of Shenzhouraptor was =
reported as 23-25=2C which is within the range of individual variation of t=
he Jeholornis holotype (22)=2C IVPP V13553 (24) and V13550 (27). The decrea=
sing count with size/age is congruent with trends seen in other basal avial=
ans. There seems to be a deeper dorsal concavity just posterior to the acro=
mion in Shenzhouraptor than the referred Jeholornis specimen IVPP V13553=2C=
 but this is poorly preserved in the Jeholornis holotype. The first metacar=
pal and phalanx I-1 in Shenzhouraptor have an "unclear" suture=2C while tha=
t in the Jeholornis holotype is obvious. Whether Shenzhouraptor's condition=
 is anatomical or taphonomic is uncertain. Phalanx II-2 is 108% of II-1 in =
Shenzhouraptor=2C but 92% in IVPP V13553 and ~96% in Jeholornis. Yet this i=
s known to vary by 28% in Deinonychus and over 80% in Struthiomimus and Dro=
miceiomimus. The third manual digit would seem to differ in the ratio betwe=
en phalanges III-2 and III-1 based on the illustration of Shenzhouraptor=2C=
 which has a ratio of ~80% compared to Jeholornis' reported ratio of <50%. =
Yet the photo of Shenzhouraptor's manus suggests an alternative identificat=
ion where the supposed proximal end of III-2 is really the distal end of II=
I-1=2C based on apparent distal condyles and phalanx outlines. Indeed=2C Ji=
 et al. only dotted in the boundary in their illustration=2C and the result=
ing ratio of ~50% matches the ~40% ratio measured in Jeholornis. The manus =
is otherwise extremely similar in the two holotypes=2C except that in Jehol=
ornis metacarpal III reaches slightly past metacarpal II. The ilia seem to =
differ in that Shenzhouraptor's has a large ventral process on the preaceta=
bular process while Jeholornis' tapers based on the illustration. Yet IVPP =
V13553 has an ilium in medial view which seems to taper as well=2C unless t=
he ventral process is taken into account=2C which is separated from the mai=
n blade by the cuppedicus fossa. In the Jeholornis holotype=2C the photo in=
dicates that the ilium is overlain by the caudal series=2C so is probably i=
n medial view as well. The ventral process would be underneath the second a=
nd third caudals and chevrons if it exists=2C so this difference cannot be =
substantiated. IVPP V13553 differs from both holotypes in having a postacet=
abular process which is blunt posteriorly. The proximodorsal ischial proces=
s in Jeholornis' holotype is expanded distally=2C while Shenzhouraptor's is=
 rounded. Perhaps more importantly=2C the ischium of Jeholornis is illustra=
ted with a pronounced dorsal kink about halfway down the shaft=2C inviting =
comparisons to the mid dorsal processes of some other maniraptorans. Shenzh=
ouraptor's is gently concave. Examination of the photo indicates that the i=
schium in Jeholornis is straight until a crack in the slab interrupts it=2C=
 after which what must have been identified as the distal ischium extends a=
t a more ventral angle. Yet this supposed distal ischium is just as parsimo=
niously a fibular fragment=2C while the true distal ischium could be undern=
eath the left tibiotarsus or right femur. The proximal metatarsus of Shenzh=
ouraptor is unfused=2C unlike the Jeholornis holotype=2C but this could be =
ontogenetic due to its smaller size. Similarly=2C the small IVPP V13553 has=
 a free distal tarsal and seems to have an unfused metatarsus. Shenzhourapt=
or was reported to have an unreversed hallux=2C while Jeholornis' was said =
to be reversed. Yet in Jeholornis the distal metatarsus is almost completel=
y destroyed by a gap in the matrix=2C all phalanges except for right digit =
IV are disarticulated=2C and the probable hallucial ungual (based on its pr=
oximal position) is oriented to curve in the same direction as five of the =
six other pedal unguals in any case. IVPP V13550 has a hallux preserved in =
unreversed position like the Shenzhouraptor holotype=2C while Li and Zhang =
(2008) find the preserved orientation depends on taphonomy in any case. In =
conclusion=2C the demonstrable differences are limited to those explainable=
 by ontogeny (caudal count=3B metatarsal fusion) or individual variation (d=
egree of ventral dentary concavity=3B distal extent of metacarpal III=3B ma=
nual digit II proportions=3B proximodorsal ischial process expansion). Thei=
r synonymy is upheld.
=20
Mickey Mortimer
The Theropod Database- http://home.comcast.net/~eoraptor/Home.html              
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