Glossary ARS - AZE
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ARSINOITHERIUM
Arsinoitherium was an early, rhinoceros-like mammal that lived during
the early Oligocene (about 38 to 23 million years ago). Although it looked
like a rhinoceros, it is more closely related to elephants. This large
quadruped had 5-toed legs. It had 2 huge, conical, hollow horns made of
bone on its snout. It was about 11.5 feet (3.5 m) long and about 6 ft
(1.8 m) tall at the shoulder. This plant eater may have lived in forests
near rivers. Fossils of Arsinoitherium have been found in Faiyum, Egypt.
Classification: Class Mammalia (mammals), Subclass Theria, Infraclass
Eutheria (placental mammals) Order Embrithopoda, Genus Arsinoitherium.
ARSTANOSAURUS
(pronounced ahr-stahn-oh-SAWR-us) Arstanosaurus (meaning: "Arstan
(Kazakhstan) lizard" ) was a lambeosaurine hadrosaur dinosaur (it
was originally though to be a ceratopsian) roughly 50 feet (15 m) long.
It was a beaked plant-eater from the late Cretaceous Period, about 87.5
million-73 million years ago. It is known from a very incomplete skeleton
found in Kazakhstan. Arstanosaurus was named by paleontologists Suslov
and Shilin in 1982. The type species is A. akkurganensis.
ARTHROPLEURA
(pronounced AHR-throw-PLOOR-ah) Arthropleura was a six-foot long myriapod
(related to millipedes), an arthropod with spines jutting out all along
the sides of its exoskeleton. This jointed animal lived in damp forests
during the Carboniferous (roughly 300 million years ago).
Arthropod
Invertebrate animals with jointed legs and an external skeleton that has
to be periodically shed as growth proceeds. The three principal groups
are the centipedes, millipedes and insects; the spiders and scorpions;
and the crustaceans. The ancestors of all these three main groups were
well developed by the end of the Cambrian period.
ARTHURDACTYLUS
Arthurdactylus conan-doylensis (named for Sir Arthur Conan Doyle, who
wrote "The Lost World") was a pterosaur (not a dinosaur). This
Pterodactyloid had an estimated wingspan 15 feet (4.6 m); this pterodactyl
has wings that were proportionately longer than any other pterosaur. Fossils
of this flying reptile were found in northeastern Brazil . This carnivore
lived during the early Cretaceous Period. Arthurdactylus was described
in 1994 by E. Frey and D. Martill.
ASIACERATOPS
(pronounced AY-zha-SER-ah-tops) Asiaceratops (meaning: "Asian horned
face") was a primitive ceratopsian, a quadrupedal, beaked, horned,
frilled, plant-eater from Kazakhstan during the late Cretaceous Period,
about 97.5 to 90 million years ago. It was about 6-7 ft (2 m) long and
weighed about 180 kg. It was similar to Montanoceratops. Only fragmentary
fossils of Asiaceratops have been found. It was named by paleontologists
Nessov and Kaznyshkina in 1989. The type species is A. salsopaludalis.
ASIATOSAURUS
(pronounced AYE-see-at-tuh-SAWR-us) Asiatosaurus (meaning: "Asian
lizard") was a large sauropod, a quadrupedal plant-eater from Mongolia
during the early Cretaceous Period. Only fragmentary fossils of Asiatosaurus
have been found. It was named by paleontologist Henry Osborn in 1924.
The type species is A. mongoliensis.
ASTEROID
An asteroid is a large rock or small planet from the belt that orbits
the sun between Mars and Jupiter. An asteroid impact with the Earth may
have caused the extinction of the dinosaurs.
ASTRODON
(pronounced AS-troh-don) Astrodon (meaning: "star-tooth") was
a long-necked plant-eating dinosaur, a brachiosaurid sauropod that was
about 30? feet (9 m) long (which is small for a brachiosaurid). It lived
during the early Cretaceous Period, about 130 million-120 million years
ago. Astrodon is known only from fossilized teeth found in Maryland, USA
(Astrodon is the state dinosaur of Maryland). Astrodon was named by Johnston
in 1859. The type species is A. johnstoni. Astrodon may be the same as
Pleurocoelus.
ATLANTOSAURUS
(pronounced at-LAN-tuh-SAWR-us) Atlantosaurus ("Atlanta lizard")
is a doubtful genus and is probably Apatosaurus. It was named by Marsh
in 1877.
ATLASCOPCOSAURUS
(pronounced AT-las-KOP-kuh-SAWR-us) Atlascopcosaurus (named for the company
Atlas Copco [Compagnie Pneumatique Commerciale], that donated some of
the equipment for the dig) was an ornithopod about 6.5 to 10 feet (2 to
3 m) long and weighed roughly 125 kg. It was a plant-eater that lived
during the early Cretaceous Period. It is known only from fossilized jaws
and teeth found in Australia. It was named by T. Rich and P. Rich in 1989.
The type species is A. loadsi
ATOM
Everything is made up of tiny atoms. An atom is the smallest part of an
element that has the properties of that element.
ATREIPUS
(pronounced ah-TREE-ih-pus) Atreipus is a poorly-known ornithischian (bird-hipped)
dinosaur known only from its fossilized tracks. No fossilized bones have
been attributed to this ichnogenus. Two sizes of footprints (4.5 and 1
cm long) have been found in conjunction, indicating that this small dinosaur
walked on four legs and its rear legs were much larger and longer than
the front legs. Atreipus was roughly 6 feet (1.8 m) long. Trackways were
found in Pennsylvania, USA Mike Szajna and Brian Hartline. It lived during
the late Triassic Period, about 220 million years ago. The type species
is Atreipus milfordensis
AUBLYSODON
(pronounced ah-BLEECE-oh-don) Aublysodon (meaning: "backwards tooth")
is a poorly-known theropod dinosaur (perhaps a tyrannosaurid) about 15
feet (4.5 m) long, weighing about 80 kg. It was a meat-eater from the
western USA during the late Cretaceous Period, about 76 million-65 million
years ago. Its front teeth were long and sharp but not serrated. It was
named by paleontologist J. Leidy in 1868. It is only known from teeth
and partial skulls. The type species is A. mirandus
AULAPODUS
Aulapodus icels is an ichnogenus, a dicynodont known from its human-sized
footprints, which were made during the Permian period, roughly 255 years
ago. According to paleontologist James Kitching, Aulapodus is Aulacephaledon,
a relatively common dicynodont known from the area. The tracks of this
plant-eating, tusked therapsid were found in the Karoo near Grahamstown,
Eastern Cape, South Africam which was a marsh during the Permian period.
Aulapodus was named by geologist Billy de Klerk in 1998. The tracks were
found by IC ''Ice'' Els, a very perceptive road builder.
AUROCHS
(pronounced OR-rox) Aurochs was a large, wild ox that lived in Europe.
This hoofed mammal (an artiodactyl) went extinct in 1627. It was black
and had forward-curving horns; it stood about 6 feet (1.8 m) tall at the
shoulder. The aurochs was the ancestor of domestic cattle. The genus and
species are Bos primigenius.
AUSKTRIBOSPHENOS
Ausktribosphenos nyktos (meaning: "Australian Cretaceous tribosphenic
mammal that lived during the night") was a small mammal that lived
during the Cretaceous period, about 115 million years ago. This insect-eater
was not a dinosaur, but it lived during the time of the dinosaurs. Its
fossilized jaw was found by Nicola Barton in 1997 at Flat Rocks, southeast
of Melbourne, Australia. Ausktribosphenos may have been nocturnal. It
is the oldest-known mammal from Australia, and was neither a marsupial
nor a monotreme (it may have been a placental mammal or a new type of
mammal). Ausktribosphenos was named by Tom Rich and Pat Vickers-Rich.
AUSTROSAURUS
(pronounced AW-stroh-SAWR-us) Austrosaurus (meaning: "southern lizard")
is a poorly-known sauropod (perhaps a cetiosaurid) dinosaur about 50 feet
(15 m) long, weighing roughly 20000 kg. It was a plant-eater during the
early Cretaceous Period, about 113 million-98 million years ago. Incomplete
fossils were found in Queensland, Australia. It was named by paleontologist
J. Longman in 1933. It is only known from teeth and partial skulls. The
type species is A. mckillopi
AUTOTROPH
(pronounced AW-toh-trofe) An autotroph (or producer) is an organism that
makes its own food from light energy or chemical energy (inorganic matter)
without eating. Most green plants, many protists (one-celled organisms
like slime molds) and most bacteria are autotrophs. Autotrophs are the
base of the food chain.
AVACERATOPS
(pronounced AY-vuh-SUR-uh-tops) Avaceratops was a small, horned, frilled
ceratopsian dinosaur about 7-14 feet (2-4 m) long, weighing roughly 1200
kg. It was a beaked plant-eater from Montana during the late Cretaceous
Period, about 77 million-73 million years ago. It was named by Canadian
paleontologist Peter Dodson in 1986. It is known from partial skulls.
The type species is A. lammersi
AVIMIMUS
(pronounced AH-vee-MIME-us) Avimimus (meaning: "bird mimic")
was a very fast moving, long-legged, bird-like theropod dinosaur about
5 feet (1.5 m) long, weighing about 14 kg. It was a long-beaked carnivore
from Mongolia during the late Cretaceous Period, about 85 million-75 million
years ago. It may have had feathers. It was named by Russian paleontologist
Sergei Mikhailovich Kurzanov in 1981. The type species is A. portentosus
AVIPES
(pronounced AH-vee-MIM-us) Avipes (meaning: "bird foot") was
a small theropod dinosaur or lagosuchian (reptiles that led to the dinosaurs)
with bird-like feet (hence its name). It was a long-beaked carnivore from
Germany during the middle Triassic Period. It was named by paleontologist
von Huene in 1932. The type species is A. dillstedtianus
AZHDARCHO
(pronounced as-DAR-choh) Azhdarcho (meaning: "dragon") was a
pterosaur, a flying reptile, not a dinosaur. It was a carnivore that lived
during the late Cretaceous Period. It is known from fossils found in Uzbekhistan.
It was named by Nessov in 1984.
AZENDOHSAURUS
(pronounced ah-ZEN-doh-SAWR-us) Azendohsaurus (meaning: "Azendoh
[Morocco] lizard") was an early plant-eating dinosaur, a prosauropod
about 6 ft (1.8 m) long. It is known only from a partial jaw and some
teeth found in Morocco. It lived during the late Triassic Period, about
228 million years ago. It was named by paleontologist Dutuit in 1972.
The type species is A. laaroussii