Re: Amazing Tendaguru and the most prolific localities in the world

[Tim Williams <twilliams_alpha@hotmail.com>]

Mike Taylor wrote:

> Yes, I quite agree that the proliferation of non-diagnostic brachiosaur 
> names isn't helping anyone.  Here in the UK alone we have Pelorosaurus, 
> Oplosaurus, Eucamerotus, Ornithopsis, "Pleurocoelus
> valdensis", perhaps Chondrosteosaurus and more.

You hit the nail on the head here.

> > At the current time, there is no evidence that more than one
> > brachiosaurid species existed in the Morrison (AFAIK).
>
> That's my understanding, too (unless anyone here knows different?)

I was informed (off-list) by a former DML member that another Morrison 
brachiosaurid is known, but not yet described.  He says that a "nearly 
complete new brachiosaurid" was "collected by the University of Kansas and 
then sent to Korea" where it is being studied by Larry Martin ("yea, the 
bird guy").  This former DML member is not sure whether the specimen was 
sent to South Korea or North Korea, but I hope it's South Korea, otherwise 
we'll probably never see the dinosaur every again (or Larry Martin either, 
for that matter!).  The skull is apparently "in pretty poor shape because 
the Koreans didn?t know what they were doing".  When and where this 
discovery will be published is unknown; Larry is apparently a very busy man. 
 I can't confirm the veracity of any of this, and i don't know from which 
part of the Morrison this alleged brachiosaur hails from.  I just thought 
I'd pass this info on.

> Ye-es.  I found Curtice and Stadtman's (2001) referral of _Dystylosaurus_ 
> to _Supersaurus_ less wholly convincing than Curtice et al.'s (1996) 
> similar job on _Ultrasaurus_;

I'm with you on that one.  Still, from memory the taphonomy supports Curtice 
and Stadtman's (2001) referral.

> I agree that the skull is certainly brachiosaurid.  The thing is, the only 
> way we know that is be reference to _B. brancai_!  There is _nothing_ to 
> make anyone think that USNM 5730 is closely related to FMNH 25107 except 
> that both of them resemble Tendaguru brachiosaur material.  So if you use 
> USNM 5730 as "evidence" to remove _brancai_ from _Brachiosaurus_, then you 
> cut off the very branch that USNM is hanging from, and it could just as 
> easily be (say) the head of
> _Haplocanthosaurus_.  (Bear in mind that one of the many positions _Haplo._ 
> has been recovered in is as a basal Macronarian.)

Yes, but I think we can be fairly certain that USNM 5730 belongs to either 
_Brachiosaurus_ or to a very close relative.

Firstly, the combination of features seen in the skull is consistent with a 
primitive titanosauriform.  I very much doubt that the skull belongs to a 
diplodocoid, or even a basal macronarian.

Secondly, USNM 5730 was found near a brachiosaurid cervical (OK, I admit 
this is hardly compelling evidence, because this Felch Quarry has lots of 
other sauropod bones.)

As for _Haplocanthosaurus_, it has been suggested that the braincase named 
_Morosaurus agilis_ may belong to _H. priscus_.

Carpenter and Tidwell point out that USNM 5730 shows a number of primitive 
characters shared by _Camarasaurus_, which is consistent with the 
proportionately longer dorsal vertebral column (relative to the humerus or 
femur) of _altithorax_ compared to _brancai_; this longer trunk is a 
primitive trait for _altithorax_.  They cite Paul (1988) for this character. 
 So Mike (or anybody else), I can't locate my copy of Paul (1988), so is 
this last character still considered a valid way of distinguishing 
_altithorax_ from _brancai_?

Cheers

Tim