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Marco Mendez wrote:


Here's some prelim info on spinosaurs from my inprep write-up (I have
papers to get before I can finish it, and there's an *Irritator*
monograph to get to finalize things.... that'll be a while):

  *Spinosaurus aegyptiacus* [Stromer, 1931] is known from the published
material and apparently _tons_ of teeth from Egypt, Tunisia, Algeria,
Morocco, and Niger. These teeth are unserrate, so are spinosaurine, and
some may pertain to the Moroccan S. moroccanus. Skull is around 4.5-5
ft in length, estimated from the dentary, which is very nearly
complete. Body lenght was probably between 45-50ft, but this was a
slender animal. The sail may not be as de Lapparent and then everyone
else after him has reconstructed; Tracy Ford has reconstructed the sail
as more compact and higher over the dorsum than the hip. The vertebrae
(and I'm not talking about the spines) are very interesting....

  *Spinosaurus maroccanus* [Russell, 1997] is known from Morocco and
some of the spinosaurine teeth from there may belong to this species
than the Egyptian one. Taquet and Russell refer a whopper of an upper
snout that beats anything theropodan known to date, as preserved it's
2ft, and as reconstructed along both baryonichine and spinosaurine
lines, in comes between 6.5 or 7ft, depending on the group you
reconstruct from. The snout may or may not pertain to maroccanus due to
lack of overlapping with the holotype, a vertebra. Even though the head
is so large, it was probably from an animal about the same size as
aegyptiacus or a little smaller, between 40-45ft or so, perhaps longer

   *Irritator challengeri* [Martill, Cruickshank, Frey, Small, &
Clarke, 1996] is from the Santana of Brazil, and represents a
half-snouted spinosaurine that has been messed up one way or another
before and since its discovery. There is no big pterosaur-like or
fin-like crest (this comes from the dislocated right maxilla) but there
is a crest similar to baryonichines. *Angaturama limai* [Kellner and
Campos, 1996] is identical in morphology to the teeth and sedimentology
it was preserved in, and most probably pertains to the same taxon, but
as Martill and others suggested at SVP in Danver, '99, they are not the
same specimen, broken off each other, as the ends do not match. There
is revision and revelation, and this taxon, which can conventionally
have the little snout summarily sunk into, is stranger than fiction.
The skull was probably 3ft. long complete and so the whole animal may
have been close to 30ft.

  *Baryonyx walkeri* [Charig & Milner, 1986] is a British baryonychine
with a relatively curvaceous snout and low dorsal spines, compared to
known spinosaurines and baryonychines with dorsal vertebrae. Keen,
microserrated teeth and lots of them with a high disparity between
uppers and lowers, its interesting to see the maxilla and dentary
together. The pelvis seems quite highly arched, interestingly enough.
It had a 3ft skull and a 30ft body, both approximated.

  *Cristatusaurus lapparenti* [Taquet and Russell, 1998] is also from
the Gadoufaoua of Niger, but differs in having a more hooked premaxilla
(as in *Baryonyx*) and a midline crest [as in *Irritator* (sensu
*Angaturama*)]. See below for further.

  *Suchomimus tenerensis* [Sereno, Beck, Dutheil, Gado, Larsson, Lyon,
Marcot, Rauhut, Sadlier, Sidor, Varricchio, Wilson, Wilson, 1998] from
the Gadoufaoua of Niger has few differences from *Baryonyx* aside from
size, shape of the sail, shape of the snout and dorsal crest with
proportion of teeth (more), more robust forelimbs and epiphyses
especially, and big olecranon. There may be a few more. I am cautious
thinking of this as a new genus, and it could serve equally well as a
species of *Baryonyx*. The skull can come out to ~4ft, and the body
about 36ft or so. Interestingly, the deep opisthocoely seen in
*Spinosaurus* and *Baryonyx* in the cervicals and anterior dorsals is
not as pronounced, and the epiphyses of the centra in these elements
are not as large, so this taxon may be closer to the primitive state
than other spinosaurids. The premaxillae of *Cristatusaurus* differ
very little from *Suchomimus*, and this is curious, because the
suchomime snouts fall between the two cristatusaur snouts in

  *Cristatusaurus lapparenti*, holotype:  185mm/95mm     (fused)
  *Suchomimus tenerensis*, holotype:      154mm/107.7mm  (part fused)
  *Cristatusaurus lapparenti*, referred:  115mm/55mm     (unfused)

  despite being a little taller; this can be considered both
ontogenetic and variable within the form. The dorsal margin of
*Suchomimus'* snout is a narrow ridge, but not a midline crest, as in
*Irritator*. The variation of the alveoli is similar, as is the
arrangement, and both bear finely serrated crowns with similar
compression (weak and sub-conical). My recommendation? They're the same

  That's it for now,

Jaime A. Headden

  Where the Wind Comes Sweeping Down the Pampas!!!!

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