Re: 3 questions (fwd)

["T. Mike Keesey" <tmk@dinosauricon.com>]

Forwarded from Jon Wagner, currently off the list.

Peter Frick wrote:

> Can anybody tell me who created the
> Euiguanodontia, Iguanodontidea and Euhadrosauria ?

    Well, the flip answer is, in order, the last ancestor of Euiguanodontia,
Iguanodontoidea and Euhadrosauria, respectively. :)

    In all seriousness, I know what you mean, so here's the poop:

    Euiguanodontia Coria and Salgado 1996, was defined in a
quasi-phylogenetic manner as (Gasparinisaura + Dryomorpha), the latter being
Dryosaurus (or -idae, if you must) and all Ankylopollexia (Camptosaurus +
Iguanodontoidea, ad inifinitum).
    Editorial comments: The taxon is perhaps a bit redundant, and comes
close to the hated, egregious no-no of "naming every node." However, in
light of the phlyogenetic study in which context this name was presented,
this is certainly understandable (how many nodes on the currently accepted
ornithischian cladogram are NOT named?!?!?!)

    Iguanodontoidea Hay 1902, I found the reference in Sereno, 1986, given
as emended (presumably because he "raised" it to a "hyperfamily"). I do not
have the paper in question, nor do I even have the reference. Perhaps George
Olshevsky can enlighten us further.
    Editorial comments: Sereno appears to have abandoned this term in favor
of Hadrosauriformes... I prefer to leave the node unnamed until I can
support Norman's contention that there is even ONE exclusive species sister
to Iguanodon. I'll probably still leave it then...

    Euhadrosauria Weishampel, Norman and Grigorescu 1993, was originally
concieved as " traditional grouping of lambeosaurines and hadrosaurines".
They apparently intended it to be defined by synapomorphies, both from their
original description, and that fact that the content has *changed*,
encompassing a more inclusive clade now including the "Fontllonga Taxon."
    Editorial comments: My take on this has been to retain the taxon (which
is, as originally concieved, synonymous with the best, IMHO, take on
Hadrosauridae) with the definition (Hadrosaurus > Telmatosaurus) rather than
picking a particular synapomorphy; this corresponds well with the authors'
current usage, and keeps their contribution to the hadrosaur nomenclatural
morass from being lost in the nomenclatural shuffle.

    Hope this helps,

    Wagner



Jonathan R. Wagner
9617 Great Hills Trail #1414
Austin, TX 78759