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Re: Horns and Beaks: New taxa and descriptions
As someone who routinely works with this material, I am not planning on using
the name Mantellisaurus. The differences between the species have existed for
some time (indeed, over 130Million years), and were recognised by Norman in his
many papers on the animals, and he never saw fit to split them. In real terms,
one name or the other merely serves to create more monospecific genera, which
in my opinion is not a desirable thing.
On Mickey's point: Vectisaurus atherfieldensis is a very confused sounding
name... most I. atherfieldensis material doesn't come from Atherfield (the
place: mainly defined as Atherfield point, which is a ledge of marine
calcareous sandstone), where the Vectis Fm (lagoonal) is overlain by the
Atherfield Clay (shallow marine). In ye olde days (where this naming problem
arises), material was labelled as having come from whichever bay it was
collected (eg. 'atherfield' 'brixton' etc). If we found and named this new
material today, we might call the specimen Iggy vectisensis or something...
later this locality naming habit changed to recalling whichever gorge (called
'chines': in the local lingo) the collector happened to walk down to get to the
beach. Consequently, locality data for much historical IOW material is a bit
dodgy.. Thankfully, if you collect enough you get a good feel for slight
variations in preservation (mainly bone colour and the nature of the siderite),
and you can
relocate which horizon bones actually came from. Iggy material from the Vectis
Fm (=Wealden Shales of old usage) is very rare.. hell, most terrestrial
vertebrates are rare there (mostly pterosaurs, croc, sharks.. it's actually
possibly considerable as a lagerstatten.. but that's something for another
study). Anyway, most Iggy atherfieldensis comes from the Wessex, and within the
Wessex, from the fire-flood mass-death-assemblage plant debris beds.
IIRC Vectisaurus derives from the old ?latin? name for the isle of wight, the
same derivation as Vectis Fm. The name Vectisaurus atherfieldensis appears
<erroneously> to contain geographical & formational references which are
potentially confusing, and also undesirable. I'm sure there's some ICZN rule
that says we can;t re-use Vectisaurus (since I. atherfieldensis came first vs
V. valdensis), but i don't really care, since it's a non-issue, and ICZN
chatter is insufferably dull.
I have not got a copy of the book yet (I'll order one when I am in the states),
so i do not know how Greg Paul addresses the issue of all the other potential
'gracile' Iguanodon species. No doubt some of the older mainland deposits have
ancestors of I. atherfieldensis in their ranks. When do we stop calling
something Iguanodon, and start using a new name? Of course, where we get a good
record, we encounter the same problems (eg. the Late Cretaceous of North
America). It is best if we have a series of species of the same genus.
I will admit that, for convenience's sake, saying Mantellisaurus may be more
desirable than our current usage (where we have 'berni' and 'atherfieldensis').
However, an additonal problem is that all the 'Iguanodon sp.' material
currently in collections should be relabelled as 'iguanodontidae indet.' , and
that's going to cause even more confusion, especially if a future uninformed
researcher suddenly thinks that mantellisaurus collections are hopelessly
sparse. Maybe in the paper Greg Paul has good reason for erecting the new
taxon, but those of us that work with it (on a daily basis for some of us)
don't see any real issue.
----- Original Message ----
From: Michael Mortimer <email@example.com>
Sent: Monday, 6 November, 2006 8:23:22 AM
Subject: RE: Horns and Beaks: New taxa and descriptions
Andrew A. Farke wrote-
>Paul, G. S. 2006. Turning the old into the new: a separate genus for the
>gracile iguanodont from the Wealden of England; pp. 69-77 in K. Carpenter
>(ed.), Horns and Beaks: Ceratopsian and Ornithopod Dinosaurs. Indiana
>University Press, Bloomington.
>Iguanodon atherfieldensis is renamed Mantellisaurus atherfieldensis.
ere synonyms of
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