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Glossary J

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(pronounced JAYN-noh-SAWR-us) Jainosaurus was a 58 feet (18 m) long sauropod, a titanosaurid dinosaur found in India. This plant-eater lived during the late Cretaceous Period. It was named by Hunt, Lockley, Lucas and Meyer in 1995.

Werner Janensch was a German paleontologist and museum curator (the Natural History Museum of Berlin) who led an expedition (with Edwin Hennig ) to the Tendaguru Beds in what is now Tanzania, Africa. That expedition found many late Jurassic period dinosaurs, including some Brachiosaurus. Janensch named Dicraeosaurus (1914) and Elaphrosaurus (1920).

(pronounced yah-NEN-chee-ah) Janenschia (named after Werner Janensch) was an 80 feet (24 m) long sauropod dinosaur found in Tanzania, Africa. Only 2 forelimbs, 3 clawed hindlimbs, and back and tail vertebrae were found. This enormous, long-necked, long-tailed plant-eater lived during the late Jurassic Period, about 156-150 million years ago. It is the earliest-known titanosaurid and was named by paleontologist Rupert Wild in 1991. The type species is J. robusta.

(pronounced jax-SAHR-toh-SAWR-us) Jaxartosaurus (meaning: "Jaxartes Lizard," for a river in Kazakhstan) was roughly 30 feet (9 m) long; it was a lambeosaurine hadrosaurid, a duck-billed dinosaur. Fragmentary fossils (just the skull roof and braincase) were found near the Jaxartes River in Kazakhstan. This wide-headed plant-eater had flat-topped teeth. It lived during the late Cretaceous Period, about 91-83 million years ago. Jaxartosaurus was named by Riabinin in 1939. The type species is J. aralensis.

Jeholodens was a triconodont, an early mammal. Jeholodens jenkinsi, named by Luo Zhexi and Ji Qiang, dates from the middle Cretaceous period, about 125 million years ago. Its almost complete fossil was recently found in Lianong, China. This long-tailed, quadrupedal mammal was about 5 inches ( cm) long. An insectivore, it had relatively advanced, grasping hands, but a primitive pelvis and hind limbs. It may have had large eyes, and may have been nocturnal (most active at night).

James A. Jensen was a US paleontologist who discovered Supersaurus (1972) and Ultrasauros (1979). He named Cathetosaurus (1988), Dystylosaurus (1985), the family Torvosauridae (1985), and Torvosaurus (with P.M. Galton, 1979).

(pronounced jang-junn-miao-SAWR-us) Jiangjunmiaosaurus is the same as Monolophosaurus.

Jibeinia was a toothed bird that lived during the early middle Cretaceous Period (the Barremian Age). It was roughly 115 mm long. Fossils (an almost complete skeleton) were found in the Yixian Formation, Hebei, China. The type species is J. luanhera, name by Hou in 2000.

Jobaria was a primtive, long-necked, long-tailed dinosaur from the early Cretaceous Period, about 135 million years ago. This sauropod was about 70 feet (21 m) long and weighed about 20 tons. It was a plant-eater that had scoop-like teeth. Jobaria was excavated by a team of paleontologists led by Paul Sereno. Several fossils were found together, indicating that this dinosaur was a herding animal. Fossils were found in a rock formation near the town of Agadez in the Sahara desert in Niger, Africa. This area was forested during the Cretaceous period. The type species is Jobaria tiguidensis. Jobaria was named for Jobar, a mythical creature of north African legends.

(pronounced juh-buhl-POOR-e-ah) Jubbulpuria was a meat-eating dinosaur that lived during the late Cretaceous Period. Jubbulpuria was roughly 1-2 m long. The type species is J. tenuis; it was named by von Huene and Matley in 1933. Fossils (2 back vertebrae) have been found in Jubbulpore, India. Jubbulpuria is a nomen dubium (since only two vertebrae have been found).

(pronounced JEW-gul) The Jugal is the cheek bone, the bone between the eye and the upper jaw.

Jurassic Period
The Jurassic period lasted from about 205 million years ago to 144 million years ago.

(pronounced jur-ASS-o-SAWR-us) Jurassosaurus nedegoapeferima (Jurassosaurus means Jurassic lizard; nedegoapeferima is fragments of the names of cast members of the movie Jurassic Park, Sam Neill, Laura Dern, Jeff Goldblum, Richard Attenborough, Bob Peck, Martin Ferrero, Ariana Richards and Joseph Mazzello). Steven Spielberg, the director of the movie "Jurassic Park," donated money for Chinese dinosaur research, so he was allowed to suggest its name. He chose Jurassosaurus nedegoapeferima, which was later changed to Ticinosaurus nedegoapeferima (by paleontologist Dong in 1993). Jurassosaurus was an armored, plant-eating dinosaur that was about 10 feet 3 m) long. It lived during the middle Jurassic Period. Fossils of this ankylosaurid were found in Xinjiang Province in northwestern China. Ticinosaurus is a Nomen Nudum.