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*Caudipteryx*: A New Family, a New Species, a New Headache



Just having read through the new paper by Zhao and
Wang (2000) on *Caudipteryx dongi*, I have the
following comments to make:

  Zhou Zhong-He and Wang Xiao-Lin, 2000. A new species
of *Caudipteryx* from the Yixian Formation of
Liaoning, northeast China. _Vertebrata PalAsiatica_ 38
(2): 111-127. [w/ Chinese abstract and summary, w/ 5
pls.]

  -----

  First, data on the specimen for those without access
to the paper:

  *Caudipteryx dongi* is diagnosed from *C. zoui* on
the following characteristics: sternum is relatively
smaller, the femorosternal ratio is higher (6 > 4.1)
mcI:mcII ratio is higher (4.5 > 4), ischium is
relatively shorter, and ilium is relatively longer.
*C. dongi* is larger than *C. zoui* by about .5ft
(.15m).

  The holotype (IVPP V12344) lacks the skull, cervical
vertebrae, anterior dorsals, and about the distalmost
10 caudals and haemal arches. It comes from
Zhangjiagou, Sihetun, in Layer 6 of the Yixian
Formation. Comparative stratigraphy is offered
elsewhere, and there are multiple Chinese and other
papers on the stratigraphy which I'm sure Josh can
summarize if he feels willing to indulge the cranial
fracture. Unique to this specimen of *Caudipteryx*, it
is very well preserved, nearly all the pubes are
preserved, there are uncinates on three consecutive
ribs, and gastralia are of the latticed type described
in dromaeosaurs (Norell and Makovicky, 1999) and
oviraptorids (Clark, Norell, and Makovicky, 1999).
There are gastroliths, and it seems to my mind this
pile is larger than in the type and paratype of *C.
zoui*. Mentioned is an uncatalogued IVPP? specimen of
the latter species. Skin impressions (along with
feathers) on the arms are present around manal digits
1, 2, the wrist, and lower forelimb of the left arm.
Scattered cervicals, dorsals, and sacrals litter the
specimen.

  Comments:

  First off, it's nice to see a well-preserved,
illustrated, and described specimen of *Caudipteryx*
from Sihetun. Now we need to see the *C zoui*
specimens treated well -- especially the skull.

  The pelvis is very well preserved, complete, and a
reconstruction is offered (it's dissarticulated);
propuby is advocated, but not demonstrated
unequivocally -- Ji et al. (1998)'s original assesment
of opisthopuby was made on the prescence of a ventral
notch in the pubic peduncle of the ilium, but the
articulation of the pubis to the ischium in *C. dongi*
shows that the only way for the pubis to articulate
was in a propubic orientation. There isn't really
anything new about the pelvis except that the two alae
are of nearly equal length, and the preacetabular ala
has a very long ventral extension, pointy ventrally.

  The pes has a supposedly attenuated mtIII, but only
along the mid-shaft, and the proximal and distal ends
were expanded in such a way that the pinched proximal
form seen in maniraptorans and a few other forms (like
*Nedcolbertia*, a maniraptoran?). The pes, the only
fully articulated one for Caudi, has a shorter 4th toe
than the 2nd, succesively shorter pedal phalanges in
all toes with the claws longer than the penultimate,
and a retroverted hallux, articulated in one pes.

  Zhou and Wang consider the avian or dinosaurian
relationship of *C. dongi*, in reference to the two
main camps of bird origins. 16 features are listed as
showing Caudi is a maniraptoran theropod outside of
Aves or Avialae, some of which are equivocal (pers.
obs.) and highly variable among extant and unequivocal
fossil avian taxa. The condition of the jugal (similar
to dromaeosaurids), derived haemal arches, unfused
sternal plates in an adult(~), mcI:mcII ratio higher
than .36, relatively long manal digit 1, large
obturator process, pubic symphysis half the length of
the pubis, and separate calcanea and astragali, are
probably the less equivocal ones (lack of a pretibial
bone, propuby, extent of the pubic peduncle of the
ilium, scapula/coracoid angle, very short forelimb
relative to hindlimb, are some of the others).

  Oviraptorosaurs are considered as likely sister
groups, but Caudi lacks many suggested synapomorphies
of oviraptorosaurs (Ji et al., 1998; Makovicky and
Sues, 1998; Xu et al., 1999) and so an indetirminate
maniraptoran relationship is advocated. In fact, Zhou
and Wang suggest a few oviraptorosaurian
synapomorphies, and a few dromaeosaurid
synapomorphies, so it is suggestable (me) there was
some basal maniraptoran features reversed by both
dromaeosaurs and oviraptorosaurs present in Caudi. Xu
(in a pers. comm. to Zhou and Wang) says Caudi has
constricted bases on the teeth. The ilium has a
shallow (reduced) fossa for the m. cuppedicus, like
birds, *Microvenator,* and oviraptorosaurs.

  All in all, trichotomy of Caudi, ovis, and dromies
is suggested as the most parsimonious analysis by Zhou
and Wang.

=====
Jaime "James" A. Headden

  Dinosaurs are horrible, terrible creatures! Even the
  fluffy ones, the snuggle-up-at-night-with ones. You think
  they're fun and sweet, but watch out for that stray tail
  spike! Down, gaston, down, boy! No, not on top of Momma!

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