Dinosaur footprints
of the Connecticut River Valley

Picture of Dilophosaur
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It must be stated at the
beginning that dinosaurs have two different naming systems. One system
is for the skeletal remains and the other system is for the tracks or
trace fossils they left behind. The reason for this is that unless a
dinosaur died in its tracks, a scientist can not know for certain which
skeleton goes with which tracks. Of the tracks that have been found, it
is not even possible to know if the skeleton has yet been found for
that particular track.
Types Of Tracks In The Connecticut River Valley
There are numerous types of
dinosaur tracks found in the sedimentary layers of the Connecticut
River Valley . Seven of the more common or more interesting are
described briefly below, but there are others . Six of these track
types are those of dinosaurs and the seventh was made by an early
ancestor of the crocodiles . There are other types of tracks found that
do not fit neatly into any of these seven categories of tracks and
scientists continue to debate whether they represent distinct footprint
types or are simply deformed footprints of these known genera.
Generally, for every inch of
track (heel to toe) there is one foot in length of the dinosaur.
A. Large Dinosaur Tracks
1. Eubrontes ("True
Thunder") track length 10-20 inches:
These tracks were made by a
large, bipedal, carnivorous, Theropod dinosaur similar to a
Dilophosaurus and are among the most common tracks found in the valley.
These dinosaurs probably reached a length of 20 feet .
The animal that made these tracks
was one of the first large meat-eating dinosaurs . Scientists studying
these tracks have compared the tracks to the foot skeleton of the
well-known dinosaur Dilophosaurus . They have noted that the foot
skeleton of the Dilophosaurus seems to fit nicely into these footprints
. Thus it is likely that an animal similar to the Dilophosaurus made
the Eubrontes tracks. Dilophosaurus is best known for its role in
Jurassic Park , where it ate the computer expert in the jeep. It's the
valley dinosaur that went to Hollywood and made it big.
2. Gigandipus
("Giant Foot") track length 10-20 inches:
These tracks were made by large,
bipedal, carnivorous, Theropod dinosaur similar to a Dilophosaurus .
The Gigandipus track is relatively rare . These dinosaurs probably
reached a length of 20 feet.
The distinctive features of these
tracks are that they show a tail dragging and the presence of a hallux
toe ( The hallux is the first toe. In humans this is the big toe , but
in most dinosaurs it was reduced and much smaller than the three
weight-bearing toes .)
These tracks are very much like
Eubrontes tracks, so much so that many scientists who study these
tracks think that they were made by the same large theropod dinosaur.
The differences may indicate that there was variability between
different animals within the genera .The presence of the hallux toe and
a tail dragging suggest to some paleontologists that the dinosaur may
have been walking low to the ground - possibly while stalking prey or
carrying something in its mouth.
3. Otozoum ("Giant Animal") track
length around 10-20 inches:
These tracks were made by large,
bipedal, Prosauropod dinosaur similar to the Plateosaurus. It is
considered to be an early prosuaropod and the track is quite rare . The
dinosaur probably reached a length of 20-30 feet .
Scientists have never found any
skeletal material for this dinosaur in the Connecticut River Valley,
but it is thought to have been an early plant-eating ancestor of the
later sauropod dinosaurs. It can be distinguished from other dinosaur
tracks in that it has four, thick, forward-pointing toes while all the
other dinosaur tracks in the valley are three-toed. Sometimes the front
feet are evident in the walkways so it must have sometimes dropped down
and walked on all four legs.
Picture of Coelophysis
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B. Medium-sized Dinosaur Tracks
4. Anchisauripus
("Close to Lizard Foot") track length 7-10 inches:
These tracks were made by a
medium-sized, bipedal, carnivorous, Theropod dinosaur similar to a
Coelophysis . This dinosaur probably reached a length of 7-10 feet.
Skeletal remains of an animal
similar to Coelophysis have been found in the valley supporting the
conclusion that it was like a Coelophysis . These tracks could have
been made by the adult version of the dinosaur that made the Grallator
tracks.
5. Grallator ("Stilt
Walker") track length 3-7 inches:
These
tracks were made by a small to medium-sized, bipedal, carnivorous,
Theropod dinosaur similar to Podokesaurus holyokensis, which was found
nearby in South Hadley, Massachusetts. These dinosaurs probably reached
a length of 3-7 feet .
These tracks were made by a
slightly smaller dinosaur than the one that made the Archisauripus
tracks, and may simply be a juvenile of that dinosaur. The stride of
their walkways show that they were probably the fastest dinosaurs in
the valley. They may have attained speeds of up to 20 miles per hour.
This is one of the most common types of dinosaur tracks found in the
Connecticut River Valley.
6. Anomoepus ("Odd
Track") track length 3-6 inches:
These
tracks were made by a small, bipedal, herbivorous, Ornithischian
dinosaur similar to a Scutellosaurus that sometimes dropped down onto
it’s front two feet so as walk on all four legs. These
dinosaurs probably reached a length of 3-6 feet .
The ornithischian dinosaurs are
the group of dinosaurs that include the familiar stegosaurs,
ankylosaurs, the horned ceratopsians, and the duckbills. Occasionally
there is a sign of a tail dragging present in the walkways. Anomoepus
was the first type of dinosaur footprint found in the Connecticut River
Valley . The first specimens were discovered near the Nash Dinosaur
Track Site in 1802 by Pliny Moody, a farmer’s son, as he plowed a
field .
C. Small Reptile Tracks
7. Batrachopus ("Frog
Foot") track length 1 inch:
These tracks were made
by an early crocodilian-like reptile similar to Stegomosuchus longipes
. The animals that made these tracks probably reached a length of 2-3
feet.
Like today’s crocodiles,
the Batrachopus track maker walked on all four legs, so both their hand
and foot impressions are found in the walkways. However, unlike
today’s crocodiles, which are aquatic, the Batrachopus animals
were fast-running land animals. It wasn’t until later that the
crocodile became a dominant aquatic carnivore . The first of these
tracks were found in East Longmeadow, Massachusetts.
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