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Re: Details on Capitalsaurus: Multiple musings....



Tom Lipka wrote-
> We do not need someone INTENTIONALLY erecting new nomina nuda-dubia , etc.,
> for capricious reasons.
 
Okay, due to advice from a certain "patient and sage individual", I've decided to leave the whole "Capitalsaurus" thing alone.  However, if I did officially name "Creosaurus" potens  Capitalsaurus (which I won't), how is that different from say... George Olshevsky naming Iguanodon exogirarum Ponerosteus.  Same situation, except at least "Capitalsaurus" is definitely not Creosaurus (or Allosaurus or Dryptosaurus), while Ponerosteus seems to be a complete mystery.  Does the ICZN say anything about having to name a new genus for a species that obviously doesn't belong in the genus which it was described, and appears to belong in no currently named genus?

> You're not scooping Kranz but you are in fact _confounding_ possibly ongoing and future work > with use of another useless name! Yours and Peter's nomenclature do not add one iota of
> information that sheds any NEW light on a largely undiagnostic vertebra! Not one! You are
> destabilizing the nomenclature!
 
I'd like to know how it would be confounding work.  The thing's neither Creosaurus nor Dryptosaurus, so the current nomenclature is misleading.  We're already stuck with the name "Capitalsaurus" in the literature for this vertebra, wouldn't it be better to formalize the name already used as opposed to continually referring to it as "Creosaurus" potens or "Dryptosaurus" potens?  Thus, I would say giving it a new genus "sheds new light" on the vertebra by indicating it does not belong to either of those genera.  Isn't that useful?

>>It's sort of a tricky situation.  Creosaurus potens (Lull, 1911) is based on
>>the same specimen as "Capitalsaurus" (Kranz, 1998).  I've verified this by
>>talking to Kranz and Lipka.  It's certainly not Allosaurus (=Creosaurus),
>>nor is it Dryptosaurus (as suggested by Gilmore 1921).  So Kranz wanted to
>>place it in a new genus, hence "Capitalsaurus". 
>
> ON what grounds? It posesses NO diagnostic features and is thus INDETERMINATE!
 
It actually _does_ possess diagnostic features compared to presently described theropod proximal caudal centra.  Nothing currently described has the combination of the ventral keel, slightly opisthocoelous centrum, tall body (1.3 times width anteriorly) and nearly flat ventral surface.  So it's not indeterminate.  The problem is that theropod caudal vertebrae are very poorly described for the most part and descriptions almost never indicate the amount of variation within the vertebral column.  Thus, the probability its unique combination of characters will hold up far in the future is low.  It's sort of like naming a theropod based on some really odd hyoids.  Sure they're unique within the hyoids that are described sufficiently, but just how many of those are there?  A similar situation arose when Howse and Milner (1993) described Ornithodesmus as a troodontid.  It was only known from a sacrum, so could only be distinguished from Saurornithoides junior among other troodontids.  They decided it was a "nomen vanum", so perhaps "Capitalsaurus" deserves this type of validity.

> Call the damn thing "Fred" if you want. That does not make it any more descriptive or
> taxonomically useful. Now if you want your name in print in some obscure "journal" only to be > consigned to the ash heap of history when someone finally does sink your nomenclature-go
> for it. A prime case in point is the paper done in part by Brenda Chinnery, myself, Mike Brett- > Surman where we in fact sunk Kranz's "Magulodon muirkirkensis" and assigned the teeth in
> question to Neoceratopsia _indet._! As it should be.
 
I'm rather confused by the fact you never mentioned the name "Magulodon muirkirkensis" in that article.  Wouldn't it have been proper to keep the name, but just conclude that it is indeterminate?  After all, the name exists in the literature already.  It's just going to end up in the nomina nuda sections of texts in the future, unconnected with a specimen.  Confusing nearly everyone as to what it really is, except those few who happen to read your neoceratopsian article and see that it refers to a tooth described by Kranz in 1996, which they might then look up to see was called "Magulodon".  Indeed, the fact "Magulodon" was originally mentioned as an ornithopod won't help matters.  I don't think authors should be allowed to "sink" a name into "taxon indet.".  It's like me selecting Embasaurus and saying the name will no longer be used and it will be hereby known only as "Neotheropoda indet.".
 
An additional question-
"Capitalsaurus" hasn't been connected to "Creosaurus" potens in the literature yet, UNLESS the Official Dinosaur Act of 1998 counts.  Seen here- http://www.dcwatch.com/archives/council12/12-538.htm , this clearly states "Capitalsaurus" is based on the specimen NMNH 3904, which is the holotype of "Creosaurus" potens.  I assume this act was published wherever such legal documents are usually published, but does this count as an actual publication that can be used to formally state "Creosaurus" potens = "Capitalsaurus"?  Although the holotype is listed, there is no valid illustration (Acrocanthosaurus?!  grumble...) and certainly no diagnosis, so this is still a nomen nudum regardless of whether it counts as published.  Nor are there any references to prior descriptions of "Creosaurus" potens, which would have made "Capitalsaurus" the valid generic name for the species (if I properly understand ICZN rules, and assuming this is properly published).  Finally, how should we properly refer to the taxon, assuming it's a nomen nudum?  If you have a properly described species and a nomen nudum genus that's been proposed for that specimen, what do you do?  Is it
 
"Capitalsaurus" potens (Lull 1911) Kranz 1998
= Creosaurus potens Lull 1911
 
 or
 
"Creosaurus" potens Lull 1911
= "Capitalsaurus" Kranz 1998

Mickey Mortimer