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The 5th cerebral nerve once more



I just finished reading

Yoichi Azuma & Philip J. Currie: A new carnosaur (Dinosauria: Theropoda)
from the Lower Cretaceous of Japan, Canadian Journal of Earth Sciences* 37,
1735 -- 1753 (?December 2000)

This paper (the description of *Fukuiraptor*) includes a long character
list, long character matrix and small cladogram. "Except where stated
otherwise, characters are derived from Holtz (1994)" which I haven't read
that closely. Character 16 is

"Braincase, trigeminal nerve, separation of ophthalmic branch within the
bone; 0, no; 1, incipient with trough in lateral surface of laterosphenoid;
2, complete with ophthalmic branch enclosed in a tube within
laterosphenoid."

As expected, *Acrocanthosaurus* and *Herrerasaurus* (the outgroup) are coded
0, *Fukuiraptor* and *Sinosauropteryx* are coded ?, Dromaeosauridae 1,
Ornithomimidae and Tyrannosauridae 2. More surprising but already discussed
onlist is 2 for *Allosaurus*, which might be a real convergence, given that
*Sinraptor* is coded 1. What is really surprising is the 1 rather than 2 for
Oviraptoridae. It contradicts everything I've read so far. Can it simply be
a typo, or is it real? Any clarification is appreciated.
(In the cladogram this character never reverses, Dromaeosauridae and
Oviraptoridae come out as sister groups, birds, Troodontidae, and
"enigmosaurs" except Oviraptoridae are not included in the cladogram, but
coelurosaur relationships are not the topic of the paper.)

*Wouldn't have thought that the geosciences library here has this journal. I
mean, it can be expected of a geosciences library, but I'd have thought they
would exhibit the newest issues rather than bury them all in the archive --
there is much more than enough room in the new journals section. BTW,
Vertebrata PalAsiatica extends back to 1957 in the same archive.