Spinosaurids differ from the other theropods by unserrated teeth, elongated skulls, and short arms and feet.
Baryonyx has for a long time been the best known of this group, then Suchomimus
popped up, with it's exciting skeleton, and before we knew it Jurassic Park 3 turned up with
Spinosaurus breaking our beloved "T. Rex"'s neck.
Baryonyx and Suchomimus are both known to have long slender skulls, with a row of
tiny needle-like teeth in the lower jaw, and big strong teeth in the upper.
They allso had a huge curved claw on the 1st finger, probably to hold onto prey with, and Suchomimus
allso featured a sail along the back.
The sail is allso about the only known elements from Spinosaurus. Beside from the sail, only some
teeth, vertebrae and other fragments are known from Spinosaurus, and S. maroccanus didn't even
pose a sail
Irritator was found in Brazil, and had a strangely shaped skull; with half of the snout (partial maxilla and premaxilla)
part of the lower jaw (dentary) missing. What was left of it the jaw
seemed toothless. Angaturama, however, is allso known from Brazil, but this species is known from a snout
(partial maxilla and premaxilla) and part of the lower jaw (dentary). What a coincidense!
As the obvious image shows Irritator and Angaturama are the same creature, and is presented as
Irritator with much more foreward pointing teeth than Baryonyx, and
much more slender skull.
There was allso a skull restoration of Irritator with a tall crest on the roof of the skull,
allmost like in Dilophosaurus, but it turned out that the crest was a jaw fragment that got lost,
and that Irritator had the typical spinosaurid triangle-shaped mini-crest on the nasal bone.