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Re: New references



Thomas Holtz wrote-

> PETER J. MAKOVICKY, MARK A. NORELL, JAMES M. CLARK, and TIMOTHY ROWE.
2003.
> Osteology and Relationships of _Byronosaurus jaffei_ (Theropoda:
> Troodontidae). American Museum Novitates: No. 3402, pp. 1-32.

Great paper.  The other side of the skull is shown, preserving a large
external mandibular fenestra and enlarged surangular foramen.  Also, the
maxillary "fenestra" is more of a fossa, as it does not perforate the bone
(besides the connection with the antorbital fenestra).  Nor is it retained
inside the antorbital fossa, as the interfenestral bar is not recessed.
Interestingly, the narial passage follows the top of the snout until it
exits on the anterodorsal corner of the antorbital fenestra, presumedly to
then curve ventrally through the posteriorly placed choanae.  This is much
like Paul's (2002) reconstruction of dromaeosaurids, but unlike the Oregon
team's endothermic reconstructions.
A new phylogenetic analysis was presented, like that of Xu et al. (2002),
but with a few taxa and 14 characters added.  These are IGM 100/44,
Ornithomimus edmontonicus, Anserimimus planinychus, Archaeornithomimus
asiaticus and an "unnamed toothed ornithomimid".  Could the latter be
"Grusimimus"?  I forget if cranial material is known for the latter, but
should be able to check soon.  Oddly, IGM 100/42 has been replaced by
Citipati osmolskae in the cladogram, I wonder if they believe this is the
correct assignment for the specimen.  Only Allosaurus was used as an
outgroup, an option Holtz has frowned upon in the past.  The topology (432
mpt's, 586 steps, Ci 0.45) is-
|--Allosaurus
`--+--+--Albertosaurus libratus
   |  `--Tyrannosaurus rex
   `--+--+--Pelecanimimus
      |  `--+--unnamed toothed ornithomimosaur
      |     `--+--Harpymimus
      |        `--+--Garudimimus
      |           `--+--Archaeornithomimus asiaticus
      |              |--Gallimimus bullatus
      |              |--Struthiomimus
      |              |--Ornithomimus edmontonicus
      |              `--Anserimimus
      `--+--Ornitholestes
         `--+--+--Alvarezsaurus
            |  `--+--Patagonykus
            |     `--+--Shuvuuia
            |        `--Mononykus
            `--+--+--+--Alxasaurus
               |  |  |--Erlikosaurus
               |  |  `--Segnosaurus
               |  `--+--Caudipteryx zhoui
               |     `--+--+--Avimimus
               |        |  |--Microvenator
               |        |  `--Chirostenotes pergracilis
               |        `--+--Oviraptor philoceratops
               |           |--"Rinchenia" mongoliensis
               |           |--Citipati osmolskae(?)
               |           |--Conchoraptor
               |           `--Ingenia
               `--+--+--+--Sinovenator
                  |  |  `--+--IGM 100/44
                  |  |     `--+--Byronosaurus
                  |  |        |--Sinornithoides
                  |  |        `--+--Troodon
                  |  |           `--+--Saurornithoides mongoliensis
                  |  |              `--Saurornithoides junior
                  |  `--+--Microraptor
                  |     `--+--Sinornithosaurus
                  |        `--+--Unenlagia
                  |           |--Velociraptor
                  |           |--IGM 100/1015
                  |           |--Deinonychus
                  |           |--Saurornitholestes
                  |           |--Adasaurus
                  |           |--Dromaeosaurus
                  |           |--Achillobator
                  |           `--Utahraptor
                  `--+--Rahonavis
                     `--+--Archaeopteryx lithographica
                        `--Confuciusornis sanctus
Unfortunately, the character list and matrix are not included, and have not
yet been placed online
(http://research.amnh.org/users/norell/matrices.html), so I cannot add the
new data to my analysis.  I was able to code Byronosaurus for several more
characters than before however.

Mickey Mortimer