Genus: Mesadactylus JENSEN & PADIAN, 1989
Etymology: "Mesa" to commemorate the Dry Mesa locality, Mesa County, western Colorado and Greek, dactylus, "finger," a traditional root of pterodacyloid names.

Species: ornithosphyos JENSEN & PADIAN, 1989
Etymology: Greek, ornitho-, "bird" and Greek, osphyos, "lower back or loin."

Holotype: BYU 2024

Locality: Dry Mesa Quarry 1, sec. 23, T.50N, R.14, on the Uncompahgre Plateau, Mesa County, western Colorado.

Horizon: Lower Upper Brushy Basin Member, Morrison Formation.

Biostratigraphy: Zone 2.

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

Material: Synsacrum.

Referred material:

BYU 2025: Left femur.

BYU 2500: Proximal right wing phalanx 1.

BYU 9483: Cervical vertebra.

BYU 9484, 9485: Dorsal vertebrae.

BYU 9486, 9487: ?Transverse processes.

BYU 9488: Right scapulocoracoid.

BYU 9489, 9490, 9491: Right humeri.

BYU 9492: Distal left ulna.

BYU 9493: Distal left radius.

BYU 9494: ?Proximal ulna.

BYU 9495: Left metacarpal IV.

BYU 9496: Metacarpal IV.

BYU 9497: Proximal left wing phalanx I.

BYU 9498: Left wing phalanx 1.

BYU 9499: Left wing phalanx 2.

BYU 9500: Proximal left wing phalanx 1.

BYU 9501: Distal left wing phalanx 1.

BYU 9502: ?Wingbone shaft.

BYU 9503: Metapodial (?Metacarpal)

BYU 9504: Manus phalanx (III-3?)

BYU 9505: Partial manus phalanx (III-2?)

BYU 9506: ?Pedal phalanx.

BYU 9507: Metapodial fragment.

BYU 9508: Phalanx.

BYU 9511: Distal right femur.

BYU 10023: Left femur.

BYU 10024: Distal left scapulocoracoid.

BYU 10025: Metapodial.

BYU 10033: Distal left metacarpal IV.


BYU: Braincase missing the dorsal edge, but with attached posterior orbit region of the left side, the left squamosal and quadrate, and much of the back of the skull including the occipital region.


BYU 9126: Cervical vertebra.

BYU 11463: Basicranium.

BYU 13033: Proximal rib.

BYU 13595: Proximal humerus.

BYU 17206, 13618: Two specimens of phalanx IV-1.

BYU 17207: Fourth Metacarpal.

BYU 17214: Femur.



Locality: Kings View Quarry near Fruita, Mesa County, Colorado.

Horizon: Member? Morrison Formation, Group?

Biostratigraphy: Zone?

Age: Age? Stage? Epoch? Late Jurassic.


Numbers: Not given: Right radius, right first wing phalax, rib(?), and manual (?) phalanx (digt, I, II or III).