Re: Ostrom Symposium: further information

["David Marjanovic" <david.marjanovic@gmx.at>]

> Check out the following webpage:
> http://www.peabody.yale.edu/collections/vp/SPproc.html

Norell, Clark & Makovicky: Phylogenetic relationships among coelurosaurian
theropods

Character 53 is
"Dorsal process of quadrate single-headed (0) or with two distinct heads, a
lateral one contacting the squamosal and a medial one contacting the prootic
(1)."

Well, I think they've seen the fossils, and they code

*Oviraptor mongoliensis* ?
*Oviraptor philoceratops* ?
*Conchoraptor gracilis* 0
Oviraptorid IGM 100/42 [ = ?*Citipati* sp. nov.] 0
*Caudipteryx zoui* [*C. dongi*, *C.* sp. nov. not included in the matrix] 0
all known alvarezsaurs (*Shuvuuia*) and birds 1
everything else 0

What's going on here? Marya´nska and Osmólska have seen the fossils, too,
and declare *Oviraptor* has state 1?!? Are the fossils so difficult to
interpret? Or is that a series typo? ~:-|

Interesting is character 65, the tetra- (0) vs. triradiate palatine (1),
often cited as a synapomorphy of *Archaeopteryx* + Pygostylia. As expected,
*Archaeopteryx* has "1"; *Shuvuuia* has that, too, and so does
*Erlikosaurus*. Comes in handy, apart from IGM 100/42 which, as the only
oviraptorosaur not coded "?", has "0". *Confuciusornis*, the only included
pygostylian, has "?".

What is IMHO really interesting is that only 2 unambiguous synapomorphies,
as they write, link *Archaeopteryx* and *Confuciusornis*:

"197. Distal tarsals separate, not fused to metatarsals (0) or form
metatarsal cap with intercondylar prominence that fuses to metatarsals early
in postnatal ontogeny (1).
198. Metatarsals not co-ossified (0) or co-ossification of metatarsals
begins proximally (1) or distally (2)." (This character must be older than
the matrix, as nothing in the latter has state 2.)

What's more, they are not unambiguous according to the character matrix, as
*Chirostenotes* has a polymorphism for 197, *Avimimus* has "1" for both 197
and 198, and *Velociraptor* has "1" for 197!

The authors are a bit more generous in recognizing a vertebra as a sacral
than some list members.

"111. Number of sacral vertebrae: 5 (0) or 6 (1), or 8 or more (2).
Ordered."

Apparently they lump 6 and 7 sacrals. All caenagnathoids, ornithomimosaurs
and troodontids with known sacra as well as *Velociraptor*, *Rahonavis* and
*Shuvuuia* get "1", *Deinonychus* gets "0/1", *Sinornithosaurus*,
*Saurornitholestes*, *Alxasaurus* (only coded segnosaur with known sacrum),
both tyrannosaurs (*Tyrannosaurus rex* and *Albertosaurus [sic] libratus*),
*Archaeopteryx* and *Caudipteryx* are coded "0", and *Confuciusornis* is the
only one with "2".