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Re: Details on Capitalsaurus: Multiple musings....
HP Mortimer replied:
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.
To paraphrase Tom, at least wait until more material comes out. ;-)
However, if I did officially name "Creosaurus" potens Capitalsaurus (which I won't),
You seem to keep missing the point that by your invoking the new name that you have done on this list, that (admittedly is a long shot) a possibility exists that that name is regarded as a published diagnosis by "someone." Or it gets picked up and published in a hardcopy article somewhere. So even if you never intended to do so, and I believe you when you say that, the possibility exists that it does in fact take root and hold.
That is essentially all that I and others have been trying to say.
how is that different from say... George Olshevsky naming Iguanodon exogirarum Ponerosteus.
having not been on list for three + months and not keeping up with the (surprising) volume of email generated on this list since I have been back, I cannot venture a comment about what George allegedly has done. One thing though, G.O. is well versed in the ICZN and Cladistics so he may have a strong reason for doing so. However, in keeping with my admonition about naming names on this (or any) list, perhaps he should have not. Again, I don't know the facts.
>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?
"Creosaurus potens," in my view, has priority (although still nomen dubium) and should be retained for historical reference only unless and until certifiably diagnostic material come to light by which time an entirely new name will likely be erected. A similar situation exists regarding the situation with Astrodon johnstoni vs. Pleurocoelus sp.
> 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.
I agree it's not Dryptosaurus nor Allosaurus because of the temporal paradox the names imply. But we really cannot determine what affinities this tailbone has with known taxa. What is a "Creosaurus"? And for that matter, what is a "Capitalsaurus"? What shared derived characters does this single bone posses to unite it with or separate it from other known taxa. What of the possibility of _pathology_ or preservation modification? None of that has been considered.
However, many of our best and brightest have looked at the same thing (up close and personal) including Ostrom, Weishampel, Holtz , etc., and reached similar conclusions.
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?
Here's what you are advocating....
"Allosaurus medius"> "Creosaurus potens"> "Dryptosaurus potens"> and the Kranz name which I won't use. (No offense) BTW, it is not Acrocanthosaurus either (much as I would have liked)!
> ON what grounds? It possesses 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.
You have essentially made my point. BUT even if an exhaustive survey was done on contemporaneous theropod proximal caudals (where there are a relatively adequate sample to work with) this one specimen may not be significant enough except as an outlier. Conversely, one may find it had affinities with something already known. Sounds like a thesis project for the upwardly mobile undergrad-grad student!
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.
I'm rather confused by the fact you never mentioned the name "Magulodon muirkirkensis" in that article.
See responces in a separate post.
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"?
It _remotely_ could be construed as such although I pray to God that is does not!
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?
It's a nomen nudum ("Creosuaurs potens") and should properly be referred to as such although it will more likely be a n. dubium.
See (Weishampel et al., 1990: The Dinosauria) p. 98
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
When and if material comes to light that has a proximal caudal similar to the type "Creosaurus potens" but is "properly described" ( read to mean _other_ associated diagnostic material) C. potens will almost certainly be scrapped and a new nomen proposed.
One last remark that needs to be made here. The whole Capitalsaurus thing arose in large part for local _political_ reasons. In order to engender sponsors for a district dinosaur, it is necessary to make politicians feel self important about it. Consider the forgoing discussion and try to sell Creosuaurs potens (and its nomenclatural history) to publicity minded and low intelligence politicians? Now instead lets call this locally found bone (it was found in DC) something that reefers to the city and voila, you get sponsors and mayoral edicts etc. Peter is very good at mobilizing the troops fort such things. He even had a group of schoolchildren attend a council meeting where the bill was being debated to drive the point home. Furthermore, it was Kranz, through similar methods, got Astrodon johnstoni named the official state dinosaur. Too bad the name Astrodon may get the heave ho as well!
Last but not least, some local humor in the same vein:
The state fossil - a Gastropod (a snail-jokingly referred to as the "state slug" in deference to the politicians here) Ecphora quadricostata from the Miocene Calvert Fm (the famous Calvert Cliffs of Maryland) was one of the first fossils from the New World to be described in the literature in Europe, ca. 1770. However, it wasn't soon enough for E. quadricostata was preoccupied by a similar gastropod from the Pliocene of Virginia! Fast forward to 1987 when Druid Wilson of the Smithsonian Institution discovered the faux pas and proposed Ecphora gardnerae. A year later, Ward and Gilinski subdivided the genus into several species and subspecies and gave us E. gardnerae gardnerae Wilson.
In 1984 E. quadricostata was adopted the Md. State Fossil. See the problem?
SOOOOO in 1994 the State Legislature had to rewrite its law supplanting E. quadricostata with E. g. gardnerae. Whew!
Maryland Geological Survey, 1993. (revised , 1994) fact Sheet No.6., 2p.
See what we in the "Free State" have to put up with! ;-)
Thomas R. Lipka
2733 Kildaire Drive
Baltimore, Md. 21234 USA