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Re: Typical and less typical types



Ah, not quite. Paratypes are all the specimens used to make the original 
diagnosis. A paratype cannot be designated after the fact. A paratype might be 
a headless skeleton and the holotype a skull with a few other bones that tie it 
to the paratype as the same species.
 
cotypes are not important anymore since the term is no longer used. We would 
call these syntypes today, a term still in use. 
 
A holotype is always a holotype, even if the name is declared a nomen dubium. 
The tooth of Paleoscincus costatus (Acad. Nat Sci of Phil. 9263) is still the 
holotype for that taxon even though the name is a nomen dubium. The name is 
just restricted to that specimen.


Kenneth Carpenter, Ph.D.
Curator of Lower Vertebrate Paleontology &
Chief Preparator
Dept. of Earth Sciences
Denver Museum of Natural History 
2001 Colorado Blvd.
Denver, CO 80205

Phone: (303)370-6392
Fax: (303)331-6492
email: KCarpenter@DMNS.org

For fun: http://dino.lm.com/artists/display.php?name=Kcarpenter

>>> David Marjanovic <david.marjanovic@gmx.at> 10/Aug/04 >>>
In mid-late July there was a discussion on the meaning of holotype, neotype,
paratype and so on. Here's how I understand the subject:

1) Holo-, syn-, co-, lecto- and neotypes are important. Para-, allo- and
paralectotypes are not.

2) Imagine someone finds one new specimen and designates it the holotype of
a new species. Then a lot of better preserved specimens are found and
referred to the same species. Then it turns out that they are not the same,
or that the holotype is undiagnostic. The normal procedure is to pick one of
the referred specimens as the holotype of a new species. But if this would
produce too much confusion, someone can petition the ICZN. The ICZN (and
_nobody else_, ignoring the ICBN...) can then decide to pick one of the
referred specimens as the neotype of the original species. The original
holotype _loses its type status_ in the process! The neotype _replaces_ it.
A species with a neotype has no holotype anymore. -- This has happened with
*Coelophysis*, and, "one level higher up", with *Iguanodon* (whose original
type species, *I. anglicus*, is a nomen dubium, so the ICZN has made *I.
bernissartensis* the new type species; *I. anglicus* is no longer the type
species of anything).

3) Imagine someone finds 5 new specimens that seem to belong to the same
species (perhaps a growth series). Being in the early 20th century or
earlier, he designates _all of them together_ the type; they are syntypes.
This practice has meanwhile been forbidden; the reason is obvious -- who
guarantees that the syntypes all belong to the same species (as IIRC has
turned out not to be the case with *Trachodon* and *Chienkosaurus*). Lots of
syntypes are, however, still haunting around; this is because a first
revisor is needed for each case. That person picks one of the syntypes and
declares it the lectotype (lectus, Latin: chosen/picked). The others become
paralectotypes in the process; as paratypes, they are not of much further
nomenclatural interest.

4) I'm not sure what a cotype is, but I think that's what syntypes are
called when there are 2 of them (perhaps supposed to show sexual
dimorphism).

5) An allotype is a special sort of paratype, namely one of the opposite sex
to the holotype. Rare, AFAIK not existing for any Mesozoic dinosaur, and, as
a paratype, not of any nomenclatural interest. (Except that it probably has
a heightened probability of becoming the neotype should one ever be needed.)

I hope all this is correct and helps! :-)