THE ANKYLOSAURIAN DINOSAURS
Middle to late Credaceus
Acanthopholis was an 18-foot-long (5.5m) animal with an armor
of rows of oval plates made from bone set in skin, and sharp
spikes along the middle of its back. The best skeleton was found
over a hundred years ago at Folkestone, southern England, in the
chalk marl rocks at the very edge of the sea.
Alberta, Canada, and Montana, USA
Ankylosaurus was the largest ankylosaur. It was over
32ft (1mm) long, and had the size and shape of a military tank.
The body and limbs were powerful and protected by spines and bone
plates. The tail was long and carried a heavy mass of bone at the
end. An armor of heavy bone plates and horns even covered the top
of the skull.
Dyoplosaurus was a large ankylosaur that was closly
reltaed in ankylosaurus. Dyoplosaurus had massive legs, and it
was 20ft (6m) long. It was as big as a military tank and probably
as heavy. Dyoplosaurus had a masive head which was 14in (35cm)
wide. The bones of the skull were heavily fused together, and
there were extra bones bone plates on top. The end of the tail
formed a club. The last ten bones by fused bone and strengthened
tendons along either side. At the very end was a great lump of
bone made from four joined blocks. The whole solid club was 4ft.
(1.3m) long and very heavy. It must have been a useful weapon
Hylaceosaurus is the oldest fairly well-known
ankylosaur. There are some partial skeletons, bt its armor is
more than often found. The aniaml was about 20ft (6m) long. It
had an armor of spines that stuck out sideways and upwards along
the back and tail. The top of the head was thick and bony. This
was one of the first dinosaues to be named frim a skeleton
discovered in Sussex, southern England, in 1833.
Kansas and Wyoming, USA
Nodosaurus was a medium-sized armored dinosaur related
to panoplosaurus and silvisaurus. It had an armor of small bony
knobs which were set in its skin all over the body. On the back
and hip region were some oval-shaped plates with small spines.
These plates and spines were not attached to the bones of the
skeleton; they sat in the animal' tough skin. This makes it
difficult to know exactly how they were arranged. Nodosaurus was
20ft (6m) long.
Alberta, Canadam and Texsas, USA
Panoplosaurus was one of the last surviving
ankylosaurus. It is known from a partial skull and skeleton. Its
head was massive, and the top of the skull was arched and curved
with large armor plates. Panoplosaurus had a narrow snout and
small ridged teeth, and it may have fed by selecting plants at
Mongolia and northern China
Pinacosaurus was a large, lightly built armored
dinosaur. It had a rounded beak and the top of its skull was
covered with small bony plates. Its eyes were set quite far back,
and its teeth were very small Pinacosaurus is remarkable for a
pair of small openings in the skull near the nostrils. The
purpose of these is not known. Pinacosaurus is related to
ankylosaurus and Dyoplosaurus, and was 12ft. (3,5m) long.
Silvisaurus was a medium-sized armored dinosaur. It
was named in 1960 from a skull and partial skeleton which show
that it was 13ft. (4m) long. Silvisaurus had a heavy head,
long neck, and a bulky body. Its body was covered with an armor
of flat honeycomb-shaped or round plates. There were some rounded
spikes sticking out sideways on the tail and part of the body. Silvisaurus
was related to nodosaurus and panoplosaurus.
Austria, France, Hungary, Romania
Struthiosaurus was the smallest known armored dinosaur.
At only 6ft. (1.8m) long, it was less than half size of its
relatives acanthopholis, nodosaurus and hylaeosaurus. Struthiosaurus
was also one of the last ankylosaurs and it is unusual because it
comes from Europe, not North America or Asia. Struthiosaurus had
a smalll head and five different kinds of bony armor: plates with
a big spine and small bones on the neck, a pair of very long
spines on the shoulders, pairs of sloping plates on the hips and
tail, and smaller spines and knobs on the sides of the body and