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Glossary AQU - ARC

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AAC - ACR - ALE - AMA - AMP - ANH - AQU - ARC - ARS

AQUATILAVIPES
Aquatilavipes is an early bird known only from its footprints, which are modern looking (not reptilian like Archaeopteryx). It lived during the early Cretaceous period, about 130 million years ago; these are the oldest-known bird tracks. Fossil footprints have been found in Canada.

ARAGOSAURUS
(pronounced AHR-ah-go-SAWR-us) Aragosaurus (meaning: "Aragón (Spain) lizard") was a large, quadrupedal plant-eating dinosaur that lived during the early Cretaceous Period, about 130-120 million years ago. This sauropod was about 60 ft (18 m) long and weighed about 28000 kg. It had a long neck, a long powerful tail, a small head, and a bulky body. It was similar to Camarasaurus. A partial fossil was found in Spain. It was named by Sanz, Buscalioni, Casanovi and Santafe in 1987. The type species is A. ischiatus.

ARALOSAURUS
(pronounced AR-a-lo-SAWR-us) Aralosaurus (meaning: "Aral Sea lizard") was a plant-eating dinosaur that lived during the late Cretaceous Period, about 95-80 million years ago. This sauropod was about 30 ft (9 m) long, and weighed roughly 5000 kg. It had a toothless beak, a stiff tail, and a bulky body. A partial fossil was found in Kazakhstan. It was named by Rozhdestvensky in 1968. The type species is A. tuberiferus.

ARARIPEDACTYLUS
Araripedactylus was a pterosaur (not a dinosaur). This Pterodactyloid had a skull 1.6 ft (50 cm) long and an estimated wingspan 16 feet (4.8 m). Fossils of this flying reptile were found in northeastern Brazil. This carnivore lived during the early Cretaceous Period. Araripedactylus was described in 1971 by L.I. Price.

ARAUCANORAPTOR
Araucanoraptor (which means "Argentinian Araucan thief") was a meat-eating dinosaur with sickle-like toe claws. It was about 8 ft (2.5 m) long. Fossils of this coelurosauris theropod were found in Argentina. Araucanoraptor lived during the late Cretaceous Period, roughly 90 million years ago. Araucanoraptor was named in 1997 by paleontologist F. Novas. The type species is A. argentinus.

Araucaria
This is the name for a group of ancient trees that survive to this day. They are tall, evergreen coniferous trees which have cones and needle-like leaves. One of the modern representatives of this group is the Monkey Puzzle tree.

ARCHAEOCERATOPS
(pronounced AHR-kee-oh-SER-a-tops) Archaeoceratops (meaning: "ancient horned-face") is the oldest-known ceratopsian dinosaur. It lived during the early Cretaceous Period, about 95-80 million years ago. A partial skeleton was found in China. It was named by Dong and Azuma in 1996. The type species is A. shimai.

ARCHAEOCETE
(pronounced AHR-kee-oh-SEAT) Archaeocetes (meaning: "ancient whales") are early whales - whales that lived during the Eocene period (roughly 55-34 million years ago) . Some archaeocetes include Pakicetus, Ambulocetus, Basilosaurus, Remingtonocetus, Dorudon, and other early whales, some of which had hind limbs.

Archaeopteryx
The oldest known which lived in the Late Jurassic period. It is known from only six skeletons and a few other disputed remains, all recovered from the Solnhofen Limestone of Germany. Archaeopteryx was about the size of a crow with well developed feathers on its forelimbs. However it retained several reptilian features, including a long bony tail, teeth in its jaws and clawed fingers on the wings. It is believed to have evolved from the dinosaurs from the dromaeosaur group.

ARCHAEORAPTOR
Archaeoraptor liaoningensis (meaning: "ancient robber from Liaoning [China]") is a newly-discovered dinosaur, which was recently found to be a fradulent fossil created by combining two separate fossils. This turkey-sized theropod was said to have lived about 120-140 million years ago. It supposedly had hollow bones, feathers, a long tail, and its shoulder girdle and breast bone were similar to those of modern birds, indicating that it may have been able to fly. Fossils of this bipedal meat-eater were found in Liaoning Province, China.

ARCHAEORNIS
Archaeornis (meaning: "ancient bird"), named in 1917 by Petronievics and Woodward, is actually Archaeopteryx (the Berlin specimen).

ARCHAEORNITHOIDES
(pronounced AHR-kee-OR-nith-OI-deez) Archaeornithoides (meaning: "Archaeornis-like [dinosaur]") was a Coelurosaurid dinosaur about 3 ft (1 m) long, weighing roughly 2 kg. This bird-like, meat-eating dinosaur had unserrated teeth. A partial skull of a juvenile Archaeornithoides was found in Mongolia. It dates from the late Cretaceous Period. This advanced theropod was named by Elzanowski and Wellnhofer in 1992. The type species is A. deinosauricus.

ARCHAEORNITHOMIMUS
(pronounced AHR-kee-or-NITH-oh-MIME-us) Archaeornithomimus (meaning: "ancient bird mimic") was a small Coelurosaurid dinosaur about 3 ft (1 m) long, weighing roughly 20 kg. This bird-like, meat-eating dinosaur had three fingers, which leads to questions about its being an ornithomimid. A partial skull of a juvenile Archaeornithoides was found in China. It dates from the late Cretaceous Period. This advanced theropod was named by Russell in 1972. The type species of this doubtful genus is A. asiaticus.

ARCHAEOZAOIC or ARCHEAN
The Archaeozoic (also called the Archean) was an eon of geologic time during which the earliest life forms evolved. One celled organisms, including blue-green algae, archaeans, and bacteria appear in the sea. This began to free oxygen into the atmosphere.The Archaeozoic lasted from 3.9 to 2.5 billion years ago. Archaeozoic means "ancient life."

AAC - ACR - ALE - AMA - AMP - ANH - AQU - ARC - ARS