Glossary TRI - TYR
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TRIGONIAS
(pronounced tri-GO-nee-us) Trigonias was one of the earliest rhinoceroses.
It lived during the early Oligocene Epoch, about 35 million years ago.
This large, plant-eating mammal was about 8 ft (2.5 m) long, had five-toed
front feet, and had more teeth than modern-day rhinos. It did not have
a snout "horn," as modern-day rhinos do. Fossils have been found
in Europe (France) and western North America (Montana). The type species
is Trigonias osborni. Classification: Order Perissodactyla (odd-toed ungulates),
Suborder Ceratomorpha (tapirs, rhinos), Family Rhinocerotidae, Genus Trigonas.
Photo courtesy of Jim Puckett.
TRILOBITE
(pronounced TRI-low-bite) Trilobites were early invertebrates with a segmented
body and an exoskeleton. Trilobites dominated the environment during the
Cambrian Period (540 to 500 MYA).
TRIMUCRODON
Trimucrodon (meaning "triply-pointed tooth"), Trimucrodon was
a small plant-eating dinosaur that lived during the late Jurassic Period,
roughly 150 million years ago. A fossilized tooth of this ornithischian
dinosaur have been found in Provincia do Estremadura, Portugal. The type
species of this genus is T. cuneatus, named by Thulborn in 1973. Due to
the lack of fossil information, this genus is a nomen dubium.
TRIOLOPHODON
Trilophodon (meaning "three crested tooth") was an ancient mammal
that lived during the Miocene - it is sometimes called Tetrabelodon. This
large Gomphothere was an ancestor of mastodons. Trilophodon was about
5 m long and 2.5 m high. It was a heavy, plant-eating animal that walked
on four column-like legs. It had a large skull, and elephant-like proboscis,
four parallel tusks (two on the top jaw, two smaller ones on the bottom
jaw), high-ridged grinding teeth, and a short tail. Fossils have been
found in Europe (France), Africa (Kenya), Asia (Pakistan), and North America
(Nebraska, South Dakota). Classification: Kingdom Animalia, Phylum Chordata,
Class Mammalia (mammals), Order Proboscidea, Suborder Elephantiodea (elephants,
mastodonts, mammoths), Family Gomphotheriidae, Genus Gomphothere.
TRIONYX
(pronounced triI-ON-iks) Trionyx is a genus of soft-shelled turtles that
first appeared during the Jurassic Period.
TRIOPS
(pronounced TRI-ops) Triops (Triops longicaudatus) are small, freshwater
crustaceans (often found in rice fields) that look a little like trilobites.
Also called tadpole shrimp, they are branchiopods with a hard exoskeleton,
and sturdy mandibles (jaws). They eat animals and plants, and are sometimes
cannibalistic. Their life span is about 20 to 40 days. Triops evolved
during the Devonian period, about 350 million years ago (long before the
dinosaurs appeared).
TROCHANTER
The trochanter is a bony bump on the femur (the thigh bone) to which large
muscles are attached.
TROÖDON
(pronounced TROH-oh-don) Troodon was a very smart, human-sized, meat-eating
theropod dinosaur from the late Cretaceous Period, about 76 to 70 million
years ago. Fossils of Troodon have been found in Montana, Wyoming (USA)
and Alberta (Canada). The type species is T. formosus.
TROPEOGNATHUS
Tropeognathus (meaning "keel jaw") was a pterosaur that lived
during the middle Cretaceous Period, about 122 to 112 million years ago.
This flying reptile ate fish and lived near the sea. A Pterodactyloid,
it had a wingspan of about 20 feet (6.2 m) and a short tail. The skull
was 2.2 feet (67 cm) long. Tropeognathus had a large beak that was enlarged
at the tip; it had many sharp teeth. Fossils have been found in the Santana
Formation in norteastern Brazil. Tropeognathus was named by Wellnhofer
in 1987. The type species is T. mesembrinus.
TROPHIC LEVEL
A trophic level is a level of the grazing food chain. For example, plant-eaters
are primary consumers; they occupy the second trophic level in the grazing
food chain.
TSINTAOSAURUS
(pronounced sin-tau-SAWR-us) Tsintaosaurus is a genus of plant-eating,
duck-billed dinosaurs (hadrosaurs) of which little is known. Tsintaosaurus
was roughly 33 ft (10 m) long. It may have had a thin, hollow bony crest
on its head (jutting forwards, or maybe backwards) but some paleontologists
think that this crest may in fact be an artifact of the fossilization
process (Tsintaosaurus may be a lambeosaurine, a crested hadrodaur). Tsintaosaurus
lived during the late Cretaceous period. Tsintaosaurus was named by Young
Chung Chien in 1958. Tsintaosaurus means "Tsintao lizard", named
for the city of Tsingtao (Ch'ing-tao or Qingdao, which means "green
island") near where the fossil was found in the Wangshi Formation,
Shandong Province, China. Tsintaosaurus may be the same as Tanius (which
was named earlier and therefore retains its name), which was a crestless
Hadrosaurid from China. Tanius was named by Carl Wiman in 1929.
Tuatara
The tuatara, Sphenedon, from New Zealand, is the most famous "living
fossil". It evolved in the Triassic around the same time as the dinosaurs.
TULLY MONSTER
The Tully monster (Tullimonstrum gregarium) was a soft-bodied sea animal
with a long proboscis that ended in a "jaw" with eight small,
sharp teeth. Tullimonstrum was an active swimmer that was a carnivore
(meat-eater). It lived roughly 280 to 340 million years ago, during the
Carboniferous period. Fossils of this unusual organism were first found
by Francis Tully in Illinois, USA, in 1958. It was named and described
scientifically by Dr. Eugene Richardson.
TUOJIANGOSAURUS
(pronounced Too-oh-gee-ANG-oh-SAWR-us) A stegosaurid, a quadrupedal, plant-eating
dinosaur about 23 feet (7 m) long with double rows of plates along its
back, a toothless beak, a long, low-hanging head, spoon-shaped teeth,
2 shoulder spikes, and a 4-spiked tail. It was from the late Jurassic
Period, about 163-150 million years ago in China. It was named in 1977
by Shiwu Zhou, Dong, Zhang, and Li.
Turtle
Turtles, with the tortoises, are a group of reptiles characterized principally
by the development of a massive protective carapace or ‘shell’. The first
turtles appeared in the Upper Triassic period and already had a fully
developed shell. These early forms were probably unable to withdraw the
head or limbs into the shell unlike many species today. In general terms
turtles are primarily aquatic while tortoises are land-living.
TYLOCEPHALE
(pronounced TY-low-SEF-ah-lee) Tylocephale (meaning "swollen head")
was a small, plant-eating dinosaur from the Late Cretaceous Period, about
80 to 75 million years ago. It was a Pachycephalosaurid (and looked a
lot like Pachycephalosaurus). It was about 7 feet (2.5 m) long and had
a domed skull (like other Pachycephalosaurids) with bony knobs around
it (almost like a crown). It had short arms, long legs, and a long, stiff
tail. Only an incomplete skull was found (in Mongolia). It was named by
paleontologists Maryanska and Osmólska in 1974.
TYLOSAURUS
(pronounced TIE-low-SAWR-us) Tylosaurus (meaning "swollen lizard")
was a mosasaur, a large, carnivorous marine reptile (but not a dinosaur)
that lived during the late Cretaceous Period. It was a powerful swimmer
that had four paddle-like limbs on a long, streamlined body. The large
head had large jaws with many teeth. It hunted fish, turtles, mollusks,
and shellfish. It was about 33-40 feet (10-12.3 m) long and had long,
sharp teeth. Fossils have been found in America (Kansas) and New Zealand.
Tylosaurus dispar was one of the largest mosasaurs.
TYLOSTEUS
Tylosteus is an old name for Pachycephalosaurus.
TYPE SPECIES
A type species is the species of an organism from which a new genus is
named. For example, Tyrannosaurus rex is the type species for the genus
Tyrannosaurus.
TYPE SPECIMEN
A type specimen is the set of fossil remains of an organism from which
a new species is named.
Tyrannosaurus
This huge two legged carnivore lived in the Late Cretaceous period. It
roamed around the forests and marshes searching for prey. Its long, serrated
teeth and enormous jaw made it a fearsome predator. It was 12.4 meters
long, and weighed five to seven tonnes.
TYRANNOSAURIDS
(pronounced tye-RAN-oh-SAW-rids) The tyrannosaurids (meaning "tyrant
lizards") were meat-eating dinosaurs (theropods) with two-fingered
hands, small arms, a large head, sharp teeth, and lond, powerful hind
legs. They lived during the late Cretaceous period. Other tyrannosaurids
included Albertosaurus, Alectrosaurus, Alioramus, Chingkankousaurus, Daspletosaurus,
Gorgosaurus, Nanotyrannus, Prodeinodon, Tarbosaurus, and Tyrannosaurus
rex.