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Re: L. laticaudus
>>"I do not remember what the paper says about the LACM specimen you refer to."
The 1981 paper just says ""?L. laticaudus, for example, attained lengths of
16.5 m, and weights of 23 tons (Morris, 1972)."
But that 1972 paper says, "Based on the computation by Colbert (1962) of about
4 metric tons for Corythosaurus sp., LACM 26757 would have weighed close to 23
The problem is that the 1981 paper refers LACM 17712, LACM 20874, LACM 17705,
LACM 17706,LACM 20876, left tibia; LACM
17711 LACM 17704, LACM 28990, LACM 17702 to the species (LACM 17715 being the
type specimen). LACM 26757 isn't mentioned in the paper at all. So we have a
size estimate for L. laticaudus that's based on a specimen never actually
assigned to L. laticaudus!
>> "In my paper on Velafrons, I rejected the name Lambeosaurus because there
>> was no reason at all to call it that genus, absolutely no autapomorphy was
>> given to support the assignment. As for the species, many differnt
>> lamebosaurines have tall broadened tails, again, not an autapomorphy. So by
>> my consideration, this taxon is undiagnosible."
Is the specimen a nomen dubium based on Morris' description, or based on the
bones themselves? That is, clearly Morris' description doesn't provide
sufficient justification to assign it to a genus -- but that doesn't
necessarily mean the specimen itself too poor to support a genus assignment.
(Where is the specimen, anyway? Morris 1981 says:
"Although all specimens collected are now at the Museum of Natural History,
Los Angeles County, they will shortly be returned to Mexico, for they are
considered to be the property of the Federal Government of Mexico, as
stipulated in original agreements allowing us permission to collect and study
these fossils. At the present time the final disposition of the specimens is
not known." (though he suggests two museums they might end up in)
Did they get given back to Mexico & in that case where are they now? Morris
does however say "Copies of the catalogued specimens are registered at these
two institutions as well as at the Museum of Natural History, Los Angeles
County." -- so there might at least be casts still there.)
>> "If you have more information there are several places to publish the
>> information. If the paper is short "Notes" within journals is a good
>> starting place."
I don't have answers, just questions...
----- Original Message -----
From: "Terry Gates" <firstname.lastname@example.org>
Sent: Wednesday, September 15, 2010 4:38:34 PM GMT -06:00 US/Canada Central
Subject: L. laticaudus
Hello. I have not read the Morris papers for years, and they in fact packed
away in my files somewhere. I do not remember what the paper says about the
LACM specimen you refer to. However, it is possible that the postcrania from
that specimen and "L. laticaudus" are the same, but also possible they are
different. In my paper on Velafrons, I rejected the name Lambeosaurus because
there was no reason at all to call it that genus, absolutely no autapomorphy
was given to support the assignment. As for the species, many differnt
lamebosaurines have tall broadened tails, again, not an autapomorphy. So by my
consideration, this taxon is undiagnosible. If you have more information there
are several places to publish the information. If the paper is short "Notes"
within journals is a good starting place. For more comments you might want to
contact David Evans at the ROM. He is an expert on all things lambeosaurine.