Dinosaur footprints
of the Connecticut River Valley

Picture of Dilophosaur |
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 large, bipedal,
carnivorous, theropod dinosaurs 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 dinosaurs. 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,
herbivorous dinosaurs 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 dinosaur
that sometimes dropped down onto its front two feet
to walk on all four legs. These footprints were made by an
early Ornithischian dinosaur. 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 farmers
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 todays crocodiles, the Batrachopus
track maker walked on all four legs, so both their hand and
foot impressions are found in the walkways. However, unlike
todays crocodiles, which are aquatic, the Batrachopus
animals were fast-running land animals. It wasnt 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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