Message 2004-06-0017: Re: First International Phylogenetic Nomenclature Meeting

Wed, 16 Jun 2004 01:15:01 +0200

[Previous by date - Fw: Pan-clades, good or bad?]
[Next by date - Fw: First International Phylogenetic Nomenclature Meeting]
[Previous by subject - Re: Directions, PhyloCode Meeting]
[Next by subject - Re: First International Phylogenetic Nomenclature Meeting]

Date: Wed, 16 Jun 2004 01:15:01 +0200
From: David Marjanovic <>
To: DML <>
Cc: PML <>
Subject: Re: First International Phylogenetic Nomenclature Meeting

----- Original Message -----
From: "Mickey Mortimer" <>
To: <>
Sent: Tuesday, June 15, 2004 11:49 PM
Subject: First International Phylogenetic Nomenclature Meeting

> As David pointed out, the abstracts for this are online-
> .  Congratulations to him for
> authoring an abstract himself.  I've not read the whole thing yet, but the
> number of definitions I find problematic amazes me.
> First, we have Gauthier's continuing insistance on apomorphy-based clades,
> which will only lead to uncertain placement on the cladogram and uncertain
> application to intermediate states.
> Diapsida Osborn 1903 = Apomorphy (1st reptile with Caiman crocodilus' two
> temporal arches/fenestra).

That name _really_ cries for an apomorphy-based definition. The apomorphy is
very unambiguous (unlike "powered flight" or "feathers"), and fossils around
the base of Diapsida often include skulls, so I don't see a serious problem

> Rhynchocephalia Guenther 1867 = Apomorphy (1st lepidosaur with Sphenodon
> punctatus' premaxillary chisels).

Probably similarly unambiguous. I just hope we can use *Sphenodontida* or
suchlike for the stem. :-)

> Crurotarsi Sereno and Arcucci 1990 = Apomorphy (1st archosaur with Caiman
> crocodilus' fully rotary, hemicylindrical, fibulocalcaneal crurotarsal

Should better retain its original stem-based definition. Ah, this will be
replaced with *Pancrocodylia*...

> Gauthier et al. also define Reptilia and Sauria to include Aves!  I mean,
> sure birds are near certainly reptiles, but why should we force it?

Recommendation 11A Example 1 (,
scroll down far down) agrees with you -- the example being *Dinosauria*.

> Reptilia Laurentus 1768 = Crown (Chelonia mydas + Sphenodon punctatus +
> Draco volans + Caiman crocodilus + Vultur gryphus).

People will consider it proven that phylogenetic nomenclature is crazy.
        Laurentius, BTW.

> Sauria MacCartney 1802 = Crown (Sphenodon punctatus +
> Draco volans + Caiman crocodilus + Vultur gryphus).

Why *Draco*?
I've never seen Sauria being used precladistically in anywhere near this
sense. It's always used as a synonym of the rarer name Lacertilia -- the
paraphyletic lizards without snakes and sometimes amphisbaenians.

> The good ol' node-stem triplet of Sauria, Lepidosauromorpha and
> Archosauromorpha is destroyed by Gauthier et al. as well.

Isn't all that old... Why not *Neodiapsida* instead of *Sauria*? Usually
names starting with Neo- describe much smaller clades than the corresponding
prefix-less names; the current *Neodiapsida* includes almost all diapsids.
I'd like a solution similar to *Sauropoda* -- *Eusauropoda* -- 
*Neosauropoda*, *Theropoda* -- "Eutheropoda" -- *Neotheropoda* and *Aves* -- 
*Euornithes* -- *Neornithes*.

> Archosauromorpha von Huene 1946 = Node (Protorosaurus speneri +
> Rhynchosaurus articeps + Caiman crocodilus).

This is really weird. Why not keeping it stem-based?

> Finally, Gauthier et al. add Compsognathus to the definition of
> Archosauria Cope 1869 = Crown (Caiman crocodilus + Compsognathus longipes
> Vultur gryphus).
> Just why are dinosaurs constrained as archosaurs?

Perhaps just to be really certain, so that the BANDits can't complain?

> Luckily, Reisz has better definitions for some of the above clades-
> Reptilia: Clade (Testudo hermani, Crocodylus niloticus, Sphenodon
> Iguana iguana)

First, *T. hermanni*. Second, I don't like this either; see my abstract.

> Diapsida: Clade (Petrolacosaurus kansensis, Iguana iguana, not Captorhinus
> aguti, Procolophon trigoniceps, Paleothyris acadiana)

Currently a heterodefinitional synonym of the apomorphy-based one. Could
stay so.

> As does Sereno (gasp!)-
> Archosauria: Crown Clade (Crocodylus niloticus and Passer domesticus)

Fine, fine. But using a nonavian dinosaur would have been even better (Rec.

> Neornithes finally gets an official definition, from Sereno-
> Neornithes: Crown Clade (Passer domesticus not Crocodylus niloticus)


> But he still can't get the hang of defining clades based on eponymous
> Nodosauridae: Clade (Panoplosaurus mirus not Ankylosaurus magniventris)
> Nodosaurinae: Clade (Panoplosaurus mirus not Sarcolestes leedsi,
> Hylaeosaurus armatus, Polacanthus foxii)
> Iguanodontia: Clade (Parasaurolophus walkeri not Hypsilophodon foxii,
> Thescelosaurus neglectus, Parksosaurus warreni, Orodromeus makelai,
> Othnielia rex, Zephyrosaurus schaffi, Yandusaurus hongheensis)
> Hadrosauriformes: Clade (Iguanodon bernissartensis and Parasaurolophus
> walkeri)
> Hadrosauroidea: Clade (Parasaurolophus walkeri not Iguanodon
> bernissartensis)


> And isn't the type species of Stegosaurus S. armatus?  Why does he use S.
> stenops?  Wagner knows to use S. armatus.

*S. armatus* is the type. *S. stenops* is better known... or at least much
more famous. Has more beautiful plates.

> Interestingly, Neornithischia seems to be the marginocephalian stem-
> Neornithischia: Clade (Triceratops horridus not Ankylosaurus magniventris,
> Stegosaurus stenops and Parasaurolophus walkeri)

Weird. Really.

> And Sereno's always right, of course, so let's define Heterodontosaurus to
> be an ornithopod! ;-)
> Ornithopoda: Clade (Heterodontosaurus tucki and Parasaurolophus walkeri)
> I'll be using Wagner's definition-
> Ornithopoda: Clade (I. bernissartensis not A. magniventris, S. armatus, or
> C. montanus)

I agree. But only one of these two definitions can survive!

> More apomorphy-based definitions, this time from Padian-
> Pterosauria (Pterosauromorpha with fourth metacarpal and digit
> to support wing membrane synapomorphic with Pterodactylus antiquus)
> Pterodactyloidea (Pterosauria with metacarpus at least 80% as long as
> humerus synapomorphic with Pterodactylus antiquus)
> So imagine Peters is right, and Longisquama and Sharovipteryx are the
> closest relatives of pterosaurs AND have elongated fourth manual digits
> support membranes.  They'd be pterosaurs.  Or are they not _wing_
> because they weren't used for flight?  But if Sharovipteryx glided using
> leg-wings, do its tiny arm wings count because they assist flight?  Ugh.
> Apomorphy-based definitions MUST STOP!

Oh, they aren't even the problem. If he's right, then *Pterosauria* _does
not exist_. Why? Because *Pterosauromorpha* is defined as a part of
*Archosauria* -- and at least *Longisquama* is most likely not an archosaur.

The problems with foggy apomorphies is recognized, though. Recommendations
9E and 9F (at the bottom of are
meant to deal with this problem. Let's hope they will be followed.

> Clarke et al. define some names-
> Theropoda Marsh 1881 = Branch (Allosaurus fragilis, not Plateosaurus
> engelhardti).
> Why not Megalosaurus bucklandii?!  They use Megalosaurus for Dinosauria
> Saurischia.


> Finally, they give us a new, difficult to apply name-
> Avipluma New = Apomorphy (1st theropod with Vultur gryphus' hollow-based,
> branched, filamentous epidermal appendages [= feathers]).
> Yeah... so that's probably less inclusive than Avetheropoda, perhaps as
> inclusive as the Sinosauropteryx+Vultur node (_currently_ Av[i]filopluma),
> definitely as inclusive as Maniraptora.  Wow, the utility is astounding
> Mickey Mortimer
> Undergraduate, Earth and Space Sciences
> University of Washington
> The Theropod Database -

I hope Recommendations 9E and 9F will be followed at length. Otherwise the
name is going to be forgotten.


Feedback to <> is welcome!