Genus: Brachysaurana STRAND, 1926
Etymology:
= Brachysaurus WILLISTON, 1897 non HALLOWELL, 1856 (Brachysaurus erythrogaster, Squamata, Tropiduridae)
Etymology:

Species: overtoni (WILLISTON, 1897) STRAND, 1926
Etymology:
= undrescribed genus overtoni WILLISTON, 1895
= Brachysaurus overtoni WILLISTON, 1897
= Ancylocentrum overtoni SCHMIDT, 1927
= Prognathodon overtoni (WILLISTON, 1897) RUSSELL, 1967

Holotype: KUVP 950

Locality: Near the top of the Pierre deposits of the Cheyenne River of South Dakota.

Horizon: Probably 100 feet or more above the level of Mosasaurus horridus, Upper Pierre Formation.

Biostratigraphy:

Age: Campanian Stage, Senonian subepoch, Upper Gulf Epoch, Late Cretaceous.

Material: Fragmentary skull, 20 vertebrae, humeri and 2 paddle bones.

Brachysaurus overtoni modified from WILLISTON, 1898.

Referred material:

Locality: 6 miles southwest of Cuny Table on Mule Creek, Shannon County, South Dakota.

Horizon: Virgin Creek Member, Upper Pierre Formation.

Biostratigraphy:

Age: Lower Maastrichtian Stage, uppermost Senonian subepoch, Gulf Epoch, Late Cretaceous.

Material:

SDSM 3393: Skull.

 

KONISHI, BRINKMAN, MASSARE & CALDWELL, 2011

Locality: Approximately 4 km NNW of Bullshead Butte, southern Alberta Province, Canada.

Horizon: Bearpaw Formation.

Biostratigraphy:

Age: Campanian Stage, Senonian subepoch, Upper Gulf epoch, Late Cretaceous.

Material:

RTMP 1983.164.001: Fragmentry skull, jaw, rib and girdle elements.

 

Locality: East side of St. Mary River about 10 km NWof Welling, southern Albeta Province, Canada.

Horizon: Lower Bearpaw Formation.

Biostratigraphy:

Age: Campanian Stage, Senonian subepoch, Upper Gulf epoch, Late Cretaceous.

Material:

RTMP 2007.034.0001: Complete skull and largely articulated postcranium lacking paddles.

 

Locality: Blood Tribe reserve lands along the west side of St. Mary River about 12 km NNW of Welling, southern Albeta Province, Canada.

Horizon: Lower Bearpaw Formation.

Biostratigraphy:

Age: Campanian Stage, Senonian subepoch, Upper Gulf epoch, Late Cretaceous.

Material:

RTMP 2002.400.0001: Nearly complete skull and largely articulated postcranium, with one incomplete scapula, associated front paddle elements, semi-articulated pelvic girdle, articulated proximal left hind paddle, adn articulated, nealry complete right hind paddle.

 

KUES & SPENCER, 1985

Locality: SE 1/4, NW 1/4 sec. 9, T33N, R1W, about 21 km south of Pagosa Springs, Archuleta County, Colorado.

Horizon: Lewis Shale.

Biostratigraphy:

Age: Late Cretaceous.

Material:

UNM LK-2: Right dentary tip, tooth, 2 posterior caudal vertebrae, posterior cervical vertebrae, and ulnae.

 

LUCAS & IKEJIRI, 2004

Locality: NMMNH 4547 (found during the construction of a house southwest of Durango), Sec 7, T34N, R10W, La Plata County, Colorado.

Horizon: Middle Lewis Shale.

Biostratigraphy: Baculites perplexus zone.

Age: Middle Campanian Stage, Senonian subepoch, Upper Gulf Epoch, Late Cretaceous.

Material:

NMMNH P-41767: Incomplete skull, including the quadrate, pieces of both lower jaws, including a dentulous piece with 7 broken teeth, 7 articulated cervical vertebrae, ribs and other bone fragments.

 

RUSSELL, 1967

Locality: Cheyenne River, 100 feet above the level of KU 1034, Custer County, South Dakota.

Horizon: Pierre Formation.

Biostratigraphy:

Age: Late Cretaceous.

Material:

KU 1034: