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Re: Archie skull pneumatics?



David Marjanovic wrote-

> (3) is wrong,

Why?  Because Scansoriopteryx also has it?

> (7) is
> wrong because of *Microraptor* -- and who knows what the prezygapophyses
in
> a pygostyle look like? --,

But Microraptor has more caudal vertebrae (24-26) than Archaeopteryx (22).
Sinornithosaurus may not (~20) though.
More important for the reduced prezygopophyseal character is the condition
in Jeholornis.

> But
> why I'm writing this to the list is that I don't know about (5) and (6). I
> expect Witmer (who else?) knows what he's writing about here (he also
cites
> himself for both), but could someone give me a broader picture of where
> these characters occur?

5.
0- Tyrannosauridae (Makovicky and Norell, 1998; 1 in Norell et al., 2001)
Ornithomimidae (Makovicky and Norell, 1998)
Erlikosaurus (Clark et al., 1994)
?Caenagnathidae (Holtz, 2000)
Oviraptoridae (Makovicky and Norell, 1998; Clark et al., 2002)
?Dromaeosaurus (Norell et al., 2001)
?Deinonychus (Norell et al., 2001)
Velociraptor (Barsbold and Osmolska, 1999)
?IGM 100/1015 (Norell et al., 2001)
1- Mononykinae (Chiappe et al., 1998)
Sinovenator (Xu et al., 2002)
Troodon (Currie, 1985; 0 in Norell et al., 2001)
Archaeopteryx (Chiappe et al., 1998)
Patagopteryx (Chiappe, 2002)
Ornithurae (Chiappe et al., 1998)

6.
0- ?Troodon (Troodontidae in Chiappe, 2001)
?Deinonychus (Chiappe et al., 1998)
?Archaeopteryx (Chiappe et al. 1998, Chiappe 2001; 1 in Chatterjee, 1999)
Confuciusornithidae (Ji et al., 1999)
1- Caenagnathidae (Sues, 1997)
Oviraptoridae (Elzanowski, 1999)
Archaeornithoides (Elzanowski and Wellnhofer, 1993)
?Gobipteryx (Chiappe, 2001)
Ornithurae (Elzanowski and Wellnhofer, 1992)

Nick Gardner wrote-

> How many non-avian theropods lack dental serrations anyway?

For coelurosaurs.....
All teeth-
Harpymimus (Currie et al., 1990)
Pelecanimimus (Perez-Moreno et al., 1994)
Incisivosaurus (Xu et al., 2002)
Mononykinae (Perle et al., 1994)
Byronosaurus (Norell et al., 2000)
Scansoriopteryx (Zhang et al., 2002)
Archaeornithoides (Elzanowski and Wellnhofer, 1993)
Premaxillary only-
Compsognathus (Ostrom 1978)
Sinosauropteryx (Currie and Chen, 2001)
Ornitholestes (Rauhut, 2000)
Caudipteryx (Ji et al., 1998)
Sinovenator (Xu et al., 2002)
Sinornithosaurus (Xu et al., 1999; first tooth has a few faint denticles on
the anterior carina)
Microraptor (Xu et al., 2000)
Outside Coelurosauria, add spinosaurines, and the premaxillary teeth of
coelophysoids.
The condition in Protarchaeopteryx is unclear, though Witmer (2002) supports
a lack of serrations.

> As for basal constriction of the teeth in non-avian theropods, I know it
is
> present in *Caudipteryx*, *Microraptor*, *Shuvuuia*, segnosaurs,
> troodontids, and perhaps *Protarchaeopteryx*?

Also Richardoestesia, Compsognathus, Ornitholestes, Pelecanimimus,
Incisivosaurus and Mononykus.

> Is it indeed present in segnosaurs and troodontids?

Yes.
Beipiaosaurus (Xu et al., 1999)
Alxasaurus (Russell and Dong, 1993)
Neimongosaurus (Zhang et al., 2001)
Erlikosaurus (Clark et al., 1994; anterior dentary teeth not constricted)
Segnosaurus (Barsbold and Maryanska, 1990)
Nothronychus (Kirkland and Wolfe, 2001)
Sinornithoides (Currie and Dong, 2001)
Byronosaurus (Norell et al., 2000)
?Saurornithoides mongoliensis (Norell et al., 2001)
Saurornithoides junior (Barsbold, 1974)
Troodon (Currie, 1987)

> There are other non-pygostylian theropods
> with very short tails, such as the avian *Jeholornis* (22), the curious
> *Protarchaeopteryx* (23), and *Caudipteryx* (22).

Protarchaeopteryx actually has an uncertain number.  23 are preserved, but
Ji et al. estimate no more than 28 were originally present.  Nomingia only
has 23 though (Barsbold et al.'s first caudal is fused to the sacrum, so I
view it as a sacral), and Yandangornis has only slightly more than 19.

Jaime Headden wrote-

> Both *Archaeopteryx* and *Bambiraptor* have incomplete preservation of
> the postorbital bar.

Bambiraptor's looks completely preserved (Burnham et al., 2000).

>   *Caudipteryx* does not have a basal constriction, and
> *Protarchaeopteryx* has them in the premaxillary teeth anyway. They also
> exist in *Pelecanimimus*, *Sinosauropteryx*, *Compsognathus*, *Eoraptor*,
> etc..

Zhou et al. (2000) state the teeth of Caudipteryx are indeed constricted at
the base.
What's the reference for constriction in Sinosauropteryx?  Figure 4b of
Currie and Chen (2001) does not appear to be, and Rauhut (2000) codes it as
0.

> Actually, *Caudipteryx* has 24.
> In both the type and paratype, as well as one referred specimen, there
> is an incomplete gap in the series, which is filled by haemal arches.
> Reconstructing the series has approximated 24 through 26, though I am
> willing to be wrong.

Not according to Ji et al. (1998) or Zhou et al. (2000).  Both the holotype
and IVPP V 12430 are reported to have 22 caudal vertebrae in their complete
tails.  I can see at least eighteen vertebrae in the holotype, including two
that fill a gap in the series.  These vertebrae are right above the gap,
making it improbable that Ji et al. missed them when counting.  The plates
of Zhou et al. are not clear enough for me to tell the condition in IVPP V
12430.

Mickey Mortimer