COELURUS
a meat-eating coelurosaurian theropod dinosaur from the Late Jurassic of North America.
Pronunciation: seel-YOOR-us
Meaning: Hollow tail
Author/s: Marsh (
1879)
Synonyms: See
below
First Discovery: Wyoming, USA
Discovery Chart Position: #57
Coelurus fragilis
Coelurus fragilis is known from a partial skeleton found strewn around Quarry 13 of Wyoming's Morrison Formation that O.C. Marsh described in 1879 as belonging to an "animal about as large as a wolf and probably carnivorous".
(Fragile hollow tail)
Etymology
Coelurus is derived from the Greek "koilos" (hollow) and "oura" (tail) because of the hollow interiors of its thin-walled vertebrae.
The
species epithet,
fragilis, means "fragile" in Latn, again referring to its vertebrae.
ZooBank registry:
urn:lsid:zoobank.org:act:EDCB4E5B-6AD3-4D19-A8D2-F62BD50F7E67.
Discovery
The first fossils of
Coelurus were found in Reed's Quarry 13 at Como Bluff in Wyoming's Morrison Formation, between September 1879 and September 1880.
The
holotype (YPM 1993) is a partial skeleton, including numerous vertebrae, partial pelvic and shoulder girdles, and much of the arms and legs.
Estimations
Timeline:
Era: Mesozoic
Epoch: Late Jurassic
Stage: Kimmeridgian
Age range: 156-151 mya
Stats:
Est. max. length: 2.5 meters
Est. max. hip height: 0.7 meters
Est. max. weight: 30 Kg
Diet: Carnivore
Coelurus agilis (Marsh, 1884)
Elaphrosaurus agilis (Russell, Beland and McIntosh, 1980)
References
• Marsh OC (1879) "
Notice of new Jurassic reptiles".
American Journal of Science, Series 3, 18(108): 501-505. DOI: 10.2475/ajs.s3-18.108.501 
• Marsh OC (1881) "
A new order of extinct Jurassic reptiles".
American Journal of Science, 21(124): 339–341. DOI: 10.2475/ajs.s3-21.124.339
• Marsh OC (1884) "
Principal characters of American Jurassic dinosaurs, Part 8: The Order Theropoda".
American Journal of Science, 27(160): 29–40. DOI: 10.2475/ajs.s3-27.160.329
• Cope ED (1887) "The dinosaurian genus
Coelurus".
American Naturalist, 21(4): 367–369. DOI: 10.1086/274464
• Marsh OC (1888) "
Notice of a new genus of Sauropoda and other dinosaurs from the Potomac Formation".
American Journal of Science, 35(205): 89–94. DOI: 10.2475/ajs.s3-35.205.89
• Ostrom JH (1980) "
Coelurus and
Ornitholestes: Are they the same?" in "
Aspects of vertebrate history: Essays in honor of Edwin Harris Colbert".
• Carpenter K, Miles C, Ostrom JH and Cloward K (2005) "Redescription of the small maniraptoran theropods
Ornitholestes and
Coelurus from the Upper Jurassic Morrison Formation of Wyoming" in "
The Carnivorous Dinosaurs (Life of the Past)".
• Holtz Jr TR (1998) "
A new phylogeny of the carnivorous dinosaurs".
Gaia, 15: 5–61
• Holtz Jr TR, Molnar RE and Currie PJ (2004) "Basal Tetanurae" in Weishampel, Dodson and Osmólska (eds.) "
The Dinosauria: Second Edition".
• Long J and Schouten P (2009) "
Feathered Dinosaurs: The Origin of Birds".
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To cite this page:
Atkinson, L.
"
COELURUS :: from DinoChecker's dinosaur archive".
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http://www.dinochecker.com/dinosaurs/COELURUS›. Web access: 06th Mar 2026.
