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Re: LAMBEOSAUR CLASSIFICATION



In a message dated 97-05-18 03:10:00 EDT, Tetanurae@aol.com writes, quoting
Jeremy Frost:

<< Jeremy Frost wrote:
 <Bactrosaurus, IMHO, is much better known than Tsintaosaurus.
  Parasaurolophus should have its own family.>
 
 Yes, in your opinion....  Almost nothing is known of _Bactrosaurus_' skull,
 which is really what is diagnostic about lambeosaurs past deciding if they
 are lambeosaurs or hadrosaurs.  _Tsintaosaurus_ on the other hand has a
 fairly good skull, and associated postcrania.  >>

There are still problems disentangling the type material of _Tsintaosaurus_,
as well as a dispute about the position and orientation of its crest.
 
<< <I'm sorry if you disagree, but these stuffy lamebrained Ivy League types
we
 have classifying these animals don't know their butts from a hole in the
ground>
 
 This is absolutely unneeded.  If you can't offer constructive criticism
 without offering unprovoked insults, I'll show you the door.>>

Agreed. There's no love lost between me and Ivy League types, but most of
them do good work and do not warrant stupid, blatant insults of the kind
offered by Frost.
 
<< <if they haven't figured out yet that they need to classify the said
animals
 by their CREST SHAPE.>
 
 This only really works on the small scale, like telling the difference
 between _Hypacrosaurus stebingeri_ and _H. altispinus_.  Remember these
 things were used for making the animals look sexy, so it is probable that
two
 closely related groups had strikingly different crest shapes.  Something
that
 I think is rather interesting is the possibility that _Parasaurolophus_ and
 _Lambeosaurus_ are closely related, as they both share a greatly reduced
 external nasal bone, compared to the giant nasal in _Corithosaurus_ and
 _Hypacrosaurus_, which might represent the plesiomorphic state for advanced
 lambeosaurs.>>

Based on postcranial anatomy as well as cranial, _Bactrosaurus_,
_Parasaurolophus_, and _Tsintaosaurus_ (the lambeosaurid portion, anyway)
seem to form a clade within Lambeosauridae, as do _Lambeosaurus_,
_Corythosaurus_, and _Hypacrosaurus_. Might be worth coining a subfamily
Parasaurolophinae for the former; in that case, the Code mandates
Lambeosaurinae for the latter.
 
<< <If that occurred, yes, there would be a Lambeosaurinae family, and
 Tsintaosaurus and Lambeosaurus would all be in it (if there's more than one
 species of each).> >>

You mean Lambeosauridae. The -inae suffix denotes a subfamily.

Jack Horner proposed creating Lambeosauridae in the Dinosaur Systematics
volume years ago. I still agree with him.
 
<< In my opinion also, there should be a lambeosaur family that is seperate
from
 the hadrosaur family.  I also think (I know, me, the heretic) that
 _Hadrosaurus_ itself should be made a _nomen dubium_ and the hadrosaur
family
 should be renamed Edmontosauridae.>>

For this family, Saurolophidae is the next available family-level name based
on an undoubtedly valid genus.

Take a look at Horner's 1992 _Prosaurolophus_ monograph.
 
<< One more thing, _Lambeosaurus_ should be said "LAM-o-saurus" since
Lawrence Lambe almost certainly said his name like "LAM" and not "LAM-bee".
 This extends to Lambeosauridae - "LAM-o-saur-i-die", and lambeosaur -
 "LAM-o-saur". >>

In combining forms, one often revives silent letters for euphony.