Re: Laelaps and Brontosauria (was Re: Resending)

[Tim Williams <twilliams_alpha@hotmail.com>]

Jaime Headden wrote:

>   Thus it's appeal is very strong. Original useage does not
> preclude name useage, and exaptation of nomenclature has been done before,
> where a name's "old" or "original" meaning (example, Coelurosauria used to
> include all the SMALL, gracile theropods, including coelophysids, as well 
> as
> traditional coelurosaurs we know and love, but NOT the big animals such as
> tyrannosaurids)

Another example is Ceratosauria.  When Marsh erected this new group it had 
only a single member: _Ceratosaurus_.  Marsh subsequently expanded the 
Ceratosauria to include _Ornithomimus_ as well!  For the next 100 years, the 
name disappeared from usage - until it was revived as the name for a new 
clade that included _Ceratosaurus_, _Dilophosaurus_ and coelophysids 
(=podokesaurids).  The "old" and "new" Ceratosauria have almost nothing in 
common - except that they both include _Ceratosaurus_.

Jay <sappororaptor@yahoo.com> wrote:

> However, unlike Ceratopsidae and Hadrosauridae, Brontosauria was only 
> prososed relatively
> recently, AND i add, well after it's syonymny with Apatosaurus was accepted 
> throughout literatue.
> Why couldn't the author of Brontosauria go with Apatosauria? Where's the 
> respect for Apatosaurus?

You'd have to ask George Olshevsky why he coined the name Brontosauria.  I 
would add that "brontosaur" was a colloquial term for sauropod dinosaurs 
long before the name "Brontosauria" was proposed.  As Jaime said, the name 
does have some intuitive appeal for historical reasons.

> However who use's Brontosauria in the literature?

Absolutely nobody.  Except for the guy who proposed the name Brontosauria, 
and he wasn't constructing a phylogeny.  The name first appeared in a 
self-published article that included a Linnean classification of dinosaurs.  
There were other quirks beside the Brontosauria entry (e.g., _Longisquama_ 
was regarded as a basal theropod).

> Why not just abandon Brontosauria? It's original announcement was because 
> of a purported
> relationship between therizinosaurs and sauropodomorphs.

For all intents and purposes, the name Brontosauria has been abandoned, 
because the name hasn't actually been used in any sauropod phylogeny.  I 
don't see it on the horizon either.

> Also, it's based on Brontosaurus, itself invalid by synonymy.

The name _Brontosaurus_ is nomenclaturally valid.  The genus is invalid, as 
long as it's considered a junior synonym of _Apatosaurus_.  However, the 
validity of _Brontosaurus_ in no way impacts on the availability of the name 
Brontosauria.

> We already have the names Plateosauridae, Plateosauria, Prosauropoda, 
> Anchisauria

Interestingly, the type specimen of _Plateosaurus_ appears to be 
non-diagnostic.  If this is the case, then _P. engelhardti_ would require a 
new type (a neotype) to ensure that the genus _Plateosaurus_ is valid.

Cheers

Tim