RE:LARGE PTEROSAURS OF EARLY CRETACEOUS MARYLAND

[Fabio Marco Dalla Vecchia <fabdalla@box1.tin.it>]

Ray Stanford wrote:<<Fabio M. Dalla Vecchia, Ph.D., said, "Actually the so
called 'giant' pterosaurs were already present during the Early Cretaceous.
Fragmentary remains have been found in Brazil and England.Giantism is not a
feature of latest pterosaurs only (see Unwin's presentation at Bozeman SVP
meeting)."
    For those few on list who may not know, Dr. Dalla Vecchia is
unquestionably very experienced regarding pterosaurs. He has many years of
experience, in fact, and is not speculating when he tells us that gigantism
is not a feature of latest pterosaurs only.
    As for me, I am only an amateur studying a vast amount of tracks from
the Early Cretaceous of Maryland, and am, therefore, certainly no expert on
pterosaurs.  But I would like agree with Dr. Dalla Vecchia by saying that
the pterosaur manus ('hand') imprints found here in Maryland (roughly 115 to
120 million years old), measure (tip of digit I to that of digit III) from a
relatively tiny 4 cm to a comparatively gigantic 22 cm, and the largest one
measures 24 cm (although that one might have been slightly enlarged by
erosion). Pes (foot) imprints finds are fewer than those of manus, probably
because a greater weight was carried upon the manus.  So, I have fewer of
these for comparison, but the smallest pes imprint found to date is 4.5 cm
long (these smaller pterosaurs leave a differently shaped pes imprint than
do the much bigger ones, suggesting a different species), while the largest
is 10 cm in length.The larger tracks from Maryland's Early Cretaceous,
thus, suggest that some very large pterosaurs imprinted the sand and silt
here, and graced the local skies.  How large?  Based on manus imprints, one
can only make a rough calculation. Based on a pterosaur manus of only 15.5
cm length (measured as earlier described), I 'guesstimated' a wing span of
22 feet, while a well-known professional paleontologist suggested 26 to 28
feet.
    If those figures are anywhere nearly accurate, then one might reasonably
estimate the wingspan of the pterosaur that made the aforementioned 22 cm
manus imprint at something over 10 meters, I suspect.  Of course, we cannot
determine what type of pterosaur left the imprints, so calculating the wing
span with any great accuracy becomes even more problematic.
    Suffice it to say, however, that some very large pterosaurs were here as
much as 50 to 55 million years before the K/T terminal event.>>

Dear Ray,
because of a bizarre reason that I do not understand, I cannot send you
this message directly (no connections to earthlink.com), thus I do it by
the list.
First of all, I thank you for your kind words.
Then, I hope that you are going to publish the footprints found in the
Lower Cretaceous of Maryland (perhaps with the review of the well-known
professional paleontologist). During the symposium in Tolouse, Kevin Padian
spectacularly argued against the pterosaurian nature of the so called
"Pteraichnid footprints", concluding that only those in Crayssac
(France)are actually pterosaur footprints. Thus, the description of new
stuff could help in shedding light on this thorny matter.
All the best
Fabio 
----------------------------
Fabio M. Dalla Vecchia, PhD
Museo Paleontologico Cittadino
Via Valentinis 134
I-34074 Monfalcone
ITALY
http://www.fante.speleo.it