Re: "E"-nough already!

["Jaime A. Headden" <qilongia@yahoo.com>]

Tommy Bradley (htomsirveaux@mybluelight.com) wrote:

<1): Is _Eoceratops_ a junior synonym of _Chasmosaurus_?  Or is it
retained as a Nomen Dubium and "possible" juvenile specimen of
_Chasmosaurus_?>

  I beleive the separation of *E. canadensis* is no longer supported as
all systematic analyses of the last decade have supported it as a
juvenile, perhaps distinct species of, *Chasmosaurus.* So far, I beleive
one and only one analysis suggests *E. canadensis* is a synonym of a
chasmosaur species, likely *C. russelli*, on the basis of the elongate
brow horns (*C. belli* has short ones, and *C. mariscalensis* is separated
geographically and may be a southern endemic, not to mention a very basal
form that may not actually be part of the stricter *Chasmosaurus*
morphotype).

<2): Is _Efraasia_ a junior synonym of _Sellosaurus_?  Or has it been
recently reestablished as a separate, valid genus?>
 
  Yates currently separates *E. diagnostica* Galton from either
*Sellosaurus* or *Plateosaurus*; all three species, since 2000-2003 have
been found to be diagnostic species, depending on the validity of the type
one finds for *P. engelhardti*, which Galton has gone to some great
lengths to resolve.

<3): What is _Euronychodon's_ current phylogenic placement?  All the
sources I found said "_Maniraptoriformes_,? "_Deinonychosauria_" and every
point in between!>

  *E. portucalensis* may not even be theropodan, as small, ziphodont,
carinate, non-denticulate and ridged teeth are not exclusive to theropods.
Though virtually all references appear to support a theropod relationship
based on these general type forms. Otherwise, *E. portucalensis* is
virtually identical to the morphotype expressed in the type of
*Paronychodon* and is distinguished only by its geography (Paro is North
American, Euro is European).

<Finally, 4): is the recently named _Epidendrosaurus_ a NON-Avian
Dinosaur? Or is it an actual Avian?>

  Onlist and off this is contentious. The original analysis Zhang et al.
(2001) supports a near-avian relationship, as a member of Aves. Mickey
Mortimer, onlist, supported an avian relationship. When characters were
corrected in Zhang et al. (onlist) and re-ran in Xu et al.s *Sinovenator*
matrix (onlist) -- as well as Holtz' 2000 GAIA matrix, which I never
posted on, but retain the analysis info for -- it was found to be a basal
maniraptoran, and the avian support almost entirely supported in the
relative length of manus and arm, which may be convergent and stem from an
apomorphic third finger length, not the second. Depending on a more
complete analysis and evaluation of such contentious things like wether to
use the proximal scapular glenoid to articulate the coracoid, whether it
is anisodactyl (hallux is backwards), and use of proportions within the
arm to identify avian clades or near-avian taxa (which have a highly
significant functional aspect in that a long arm can serve more functions
than flying, and both *Epidendrosaurus* and *Scansoriopteryx* lack
pennaceous feathers one would expect if it were an avian or avialean with
long arms (or even short)), this position may change.

  Cheers,

=====
Jaime A. Headden

  Little steps are often the hardest to take.  We are too used to making leaps 
in the face of adversity, that a simple skip is so hard to do.  We should all 
learn to walk soft, walk small, see the world around us rather than zoom by it.

"Innocent, unbiased observation is a myth." --- P.B. Medawar (1969)

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