[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

Re: Coelurus a maniraptoran (for how long?)

I've been going over Holtz (2000), which has caused me to re-evaluate some
of my characters.  Because of this, there are a few comments I would like to
make.  I wrote-

> 45.  Humeral distal condyles mainly located on distal (0), or cranial (1)
> aspect.
> Also known in tyrannosaurids, segnosaurs and troodontids.

Holtz codes these as lacking the derived condition.  My original data came
Tyrannosauridae- Forster et al. 1998, Xu et al. 1999
The authors code tyrannosaurids as "1" in their matrix.
Segnosauria- Xu et al. 1999
"As in other therizinosauroids, the humerus (of Beipiaosaurus) has ...
anteriorly positioned radial and ulnar condyles on its distal end"
Troodontidae- Forster et al. 1998, Xu et al. 1999, Xu et al. 1999, Xu et al.
These groups of authors code troodontids as having the derived condition.
And yes, the two Xu et al. 1999's are different.  One is the Beipiaosaurus
description, the other the Sinornithosaurus description.  Of course, it's a
possibility Xu et al. simply took the codings directly from Forster et al.,
in which case it's a question of whether Foster et al. or Holtz is correct.
Tom knows his tyrannosaurids, so I've changed my coding of them to "0" to
reflect this.  I tend to trust written statements more than codings, so I'm
more likely to believe Xu et al. regarding segnosaurs.  Jaime also believes
segnosaurs have the derived state.  So I'm keeping them coded as "1" with
some caution.  The only troodontid humeri published are those of
Sinornithoides, which are not described or illustrated well enough to
determine the position of the distal condyles.  I'm therefore uncertain as
to the condition in troodontids.  Maybe someone can enlighten me.

> Confuciusornis only fuses metacarpal I with
> the semilunate.

I was just confused here.  Confuciusornis fuses metacarpals II and III
proximally to the semilunate and each other.  Metacarpal I remains separate.

Mickey Mortimer