Species: fragilis MARSH, 1879
Etymology: Latin, fragilis, "fagile."

Syntypes: YPM 1991, 1992, 1993

Locality: Reed's YPM Quarry 13, T22N, R76W, Sec. 4 or 5, Como Bluff, East (East of Marshall road), Albany County, Wyoming.

Horizon: Salt Wash Member, Morrison Formation.

Biostratigraphy: Zone 2.

Age: Comobluffian age, Kimmeridgian Stage, uppermost Malm Epoch, Late Jurassic.

Material:

YPM 1991: 2 proximal caudal vertebrae, 1 proximal caudal centrum, 1 proximal caudal neural arch.
Note: A young individual.

YPM 1992: 8 mid-caudal vertebrae, 1 partial centrum of a mid-caudal vertebra.

YPM 1993: 1 cervical vertebra and 1 proximal caudal neural arch.

Referred material:

YPM 1994: 1 caudal centrum.

YPM 1995: 1 caudal vertebra plus fragments.

YPM 9162: 1 partial sacral vertebra.

 

CARPENTER, MILES, OSTROM & CLOWARD, 2005

Locality: Cleveland-Lloyd Dinosaur Quarry, approximately 20 miles south of Price, SE 1/4, SE 1/4, Sec. 21, T17S, R11E, SLBM. lat 39°19’00", Long. 110°41’15"W, San Rafael Swell Area, Carbon County, Utah.

Horizon: Upper or Brushy Basin Member, Morrison Formation.

Biostratigraphy: Zone 3.

Age: Comobluffian age, Kimmeridgian Stage, uppermost Malm Epoch, Late Jurassic.

Material:

UUVP 11743: ?Left humerus.

UMNH 7795: Left humerus.

 

MARSH, 1896

Locality: ?Quarry, Como Bluff, Wyoming.

Horizon: Morrison Formation.

Biostratigraphy: Zone ?

Age: Age?, Stage?, Epoch?, Late Jurassic.

Material:

YPM 1271: Tooth.

 

GILMORE, 1909/1920

Locality: Reeds YPM Quarry 9, (Mammal Quarry), T22N, R77W, Sec. 12, Como Bluff, Albany County, Wyoming.

Horizon: Brushy Basin Member, Morrison Formation.

Biostratigraphy: Zone 3.

Age: Comobluffian age, Kimmeridgian Stage, uppermost Malm Epoch, Late Jurassic.

Material:

USNM 1992: Caudal vertebrae.

USNM 1993: Vertebra.

USNM 5809: Sacral vertebra.

USNM 5810: Cervical vertebra.

USNM 6624, 6625, 6626, 6628: Caudal vertebrae.

USNM 6627: Distal caudal vertebra.

 

 

 

OSTROM & McINTOSH, 1966

Locality: Reed’s YPM Quarry 8, T22N, R77W, Sec. 11, Como Bluff West (west of Marshall Road), Albany County, Wyoming.

Horizon: Brushy Basin Member, Morrison Formation.

Biostratigraphy: Zone 3.

Age: Comobluffian age, Kimmeridgian Stage, uppermost Malm Epoch, Late Jurassic.

Material:

Number: Not given:

 

Locality: Marsh-Felch’s YPM Quarry 1, Garden Park, Sec. 28, T17S, R70W, Canyon City, Fremont County, Colorado.

Horizon: Salt Wash Member, Morrison Formation.

Biostratigraphy: Zone 2.

Age: Comobluffian age, Kimmeridgian Stage, uppermost Malm Epoch, Late Jurassic.

Material:

Number: Not given:

 

= Coelurus agilis MARSH, 1884
Etymology: Latin, agilis, "agile."
= Elaphrosaurus agilis (MARSH, 1884) RUSSELL, BELAND, & McINTOSH, 1980

Holotype: YPM 2010

Locality: Reed's YPM Quarry 13, T22N, R76W, Sec. 4 or 5, Como Bluff, East (East of Marshall road), Albany County, Wyoming.

Horizon: Salt Wash Member, Morrison Formation.

Biostratigraphy: Zone 2.

Age: Comobluffian age, Kimmeridgian Stage, uppermost Malm Epoch, Late Jurassic.

Material: Right dentary?, 3 cervical vertebrae, 2 dorsal vertebrae, 5 dorsal centra, 6 dorsal neural arches, 2 indeterminate neural arches, 1 proximal caudal vertebra, left and right ulnae, distal ends of both radii, left humerus, left femur, proximal end of right femur, both pubes, fragment of an ilium? distal three-quarters of left tibia, proximal end of left fibula, right scapula, distal end of metatarsal III, metatarsal II or IV, left and right radial, left and right metacarpal II, right metacarpal III, fragment of right metacarpal IV, 7 phalanges of the manus, and many unidentified fragments.

A) Cervical; B) Dorsal; and C) Caudal vertebrae, after Marsh, 1884.

After Marsh, 1884.

Pubis after Carpenter et al. 2005.

Modified from Marsh,

 

Metatarals after Carpenter et al. 2005: A) distal end of metatarsal III, and B) Left metatarsal IV.

Modified from Carpenter, Miles, Ostrom & Cloward, 2005.

Possible dentary of YPM 2010, however, Carpenter, Miles, Ostrom & Cloward, 2005 are skeptical of its association.

Note: Ostrom 1995 states that there is semilunate carpal.

Referred material:

WELLES & LONG, 1974

YPM 1252: Astragalus.