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RE: [dinosaur] Tyrannosaurs and Deinodons (was re New Konzhukovia species (temnospondyl) from Permian of South America + Early Triassic polar coprolites + more papers

Tim Williams wrote-

>> Were Deinodontidae and Deinodontoidea actually created, or is their
>> existence assumed based on backforming from _Deinodon_ & the higher clades
>> which were named for _Tyrannosaurus_?
>> (I've seen backforming in linguistics, but not in nomenclature)
> Deinodontidae was named by Brown (1914). Same for Deinodontoidea.

Actually by Cope (1866) as Dinodontidae, but Brown (1914) was the first to 
emend it to Deinodontidae (Dinodon is a genus of snake).  If Deinodontidae were 
named in 1914, we wouldn't have a problem since Tyrannosauridae was named 
before that by Osborn (1906).

But yes, Deinodontoidea was actually backformed from Deinodontidae due to ICZN 
rules where naming one family-level taxon implicitly names all the others.  
Deinodontoidea wasn't explicitly used until Tatarinov (1964), but has Cope 1866 
as it's authorship.

References- Cope, 1866. [On the remains of a gigantic extinct dinosaur, 
  from the Cretaceous Green Sand of New Jersey]. Proceedings of the Academy of 
  Natural Sciences of Philadelphia. 18, 275-279.

  Osborn, 1906. Tyrannosaurus, Upper Cretaceous carnivorous dinosaur (Second 
  communication). Bulletin of the American Museum of Natural History. 22(16), 

  Brown, 1914. Cretaceous Eocene correlations in New Mexico, Wyoming, Montana. 
  Bulletin of the Geological Society of America. 25, 355-380.
Tatarinov, 1964. Nadotryad Dinosauria. Dinozavry. In Orlov (ed.). Osnovy 
  12, 523-589.

> I'm referring to species-based definitions (e.g., Tyrannosauridae =
> least inclusive clade containing _Tyrannosaurus rex_, Gorgosaurus
> libratus_, and _Albertosaurus sarcophagus_). I don't think
> character-based definitions are helpful. Phylogenetic definitions are
> best left separate to character-based diagnoses.

I agree they're problematic, but character-based definitions do exist and are 
accepted in the draft Phylocode.

>> But why stop at that half-measure? Why not give the boot to the ICZN genera
>> and species (and subspecies and superspecies and subgenera and other things
>> I've heard of over the years) ? What makes genus and species worth
>> saving, when nothing else is?
> I don't think we need to resort to this reductio ad absurdum
> argument. It's not about "saving" families. It's an issue over
> whether family-level clades should be subjected to ICZN rules
> regarding nomenclatural priority (= which ones were named first),
> irrespective of how and when they were first defined as clades. ICZN
> should continue to have jurisdiction over genera and species (and
> subspecies, subgenera, etc). But I don't see the sense in the ICZN
> deciding the validity of familes when these same families are also
> clades. Priority and validity of *all* suprageneric clades should be
> decided by phylogenetic nomenclature.

It's actually a good question.  We've now had some Mesozoic dinosaur genera and 
species phylogenetically defined.  Clarke (2004) defined Apatornis as 
(Apatornis celer <- Ichthyornis dispar, Struthio 
  camelus, Tetrao major, Vultur gryphus).  If we find some previously named 
genus to be closer to Apatornis than Struthio, Tetrao or Vultur, do we have to 
preserve Apatornis like we preserve Tyrannosauroidea?  If not, why not?  Your 
argument is that family-level taxa aren't special, so I don't see an out for 
you besides special pleading.

Mickey Mortimer
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