Species: canadensis GILMORE, 1928
Etymology: In reference to Canada, where the specimen was discovered.

Holotype: USNM 10864

Locality: Near Steveville, Red Deer River, Newell County, Alberta Province, Canada.

Horizon: Dinosaur Park Formation, upper Judith River Group.

Biostratigraphy:

Age: Judithian age, Middle Campanian Stage, middle Senonian subepoch, upper Gulf Epoch, Late Cretaceous.

Material: Dorsal vertebra.

Referred material:

BRYANT, 1990

Locality: Eastern Montana.

Horizon: Hell Creek Formation.

Biostratigraphy:

Age: Lancian age, upper Maastrichtian Stage, uppermost Senonian subepoch, Upper Gulf Epoch, Late Cretaceous.

Material:

UCMP 130716: Dentary.

UCMP 130717-130723: Vertebrae.

 

CURRIE, 1986

Locality: Dinosaur Provincial Park, Newell County, Alberta Province, Canada.

Horizon: Dinosaur Park Formation, upper Judith River Group.

Biostratigraphy:

Age: Judithian age, Middle Campanian Stage, middle Senonian subepoch, upper Gulf Epoch, Late Cretaceous.

Material:

Number: Not given:

 

ESTES, 1964

Locality: UCMP V-5003, S 1/2, Sec. 20, T37N, R64W, Lance Creek, Powder River Basin, Niobrara County, Wyoming.

Horizon: Lance Formation.

Biostratigraphy:

Age: Lancian age, upper Maastrichtian Stage, uppermost Senonian subepoch, Upper Gulf Epoch, Late Cretaceous.

Material:

UCMP 49862: Caudal vertebra.

 

Locality: UCMP V-5620, Lull Quarry, near the head of a tributary of Buck Creek, Powder River Basin, Niobrara County (Formerly Converse County), Wyoming.

Horizon: Lance Formation.

Biostratigraphy:

Age: Lancian age, upper Maastrichtian Stage, uppermost Senonian subepoch, Upper Gulf Epoch, Late Cretaceous.

Material:

UCMP 46051: Dorsal vertebra.

UCMP 49952, 49953, 49954, 49955, 49956: Teeth.

 

Locality: UCMP V-5711, Bushy Tailed Blowout, Quarry area includes the floor of a small blowout approximately 10 yards northwest of the highest point on the ridge forming the northeastern side of the blowouts of loc. V-5003, S 1/2, Sec. 20, T37N, R64W, Lance Creek, Powder River Basin, Niobrara County, Wyoming.

Horizon: Lance Formation.

Biostratigraphy:

Age: Lancian age, upper Maastrichtian Stage, uppermost Senonian subepoch, Upper Gulf Epoch, Late Cretaceous.

Material:

Unnumbered: Caudal vertebra.

 

Locality: UCMP V-5815, Hatcher Number 2, western side of a cross-stratified sandstone erosional remnant near the center of a large blowout on the crest of a ridge, the distance form the nearest point on the road, approximately 150 yards south of the quarry, to the Johnson ranch is 0.4 miles, Niobrara County (Formerly Converse County), Eastern Wyoming.

Horizon: Lance Formation.

Biostratigraphy:

Age: Lancian age, upper Maastrichtian Stage, uppermost Senonian subepoch, Upper Gulf Epoch, Late Cretaceous.

Material:

UCMP 50047: Tooth.

 

ESTES, 1984

Locality: Lance Creek, Niobrara County, Wyoming.

Horizon: Lance Formation.

Biostratigraphy:

Age: Lancian age, upper Maastrichtian Stage, uppermost Senonian subepoch, Upper Gulf Epoch, Late Cretaceous.

Material:

PU 16767-16768: Vertebrae.

YPM: Vertebrae.

 

ESTES, BERBERIAN & MESZOELY 1969

Locality: Bug Creek Anthills locality, McCone County, Montana.

Horizon: Hell Creek Formation.

Biostratigraphy:

Age: Lancian age, upper Maastrichtian Stage, uppermost Senonian subepoch, Upper Gulf Epoch, Late Cretaceous.

Material:

MCZ 3665: Vertebra.

 

Locality: Alberta Province, Canada.

Horizon: Judith River Formation.

Biostratigraphy:

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

Material:

UA 112, GSC 8510, AMNH: Vertebrae.

 

GAO & FOX, 1996

Locality: Sandy Point, and nearby localities, Newell County, Alberta Province, Canada.

Horizon: Oldman Formation, middle Judith River Group.

Biostratigraphy:

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

Material:

UALVP 33337: Tooth-bearing dentary.

UALVP 33339-33345: 7 isolated vertebrae.

 

Locailty: Microfossil sites at Dinosaur Provincial Park, and nearby localities, Newell County, Alberta Province, Canada.

Horizon: Dinosaur Park Formation, upper Judith River Group.

Biostratigraphy:

Age: Judithian age, Middle Campanian Stage, middle Senonian subepoch, upper Gulf Epoch, Late Cretaceous.

Material:

RTMP 80.29.120, 80.20.37: Incomplete maxillaries.

RTMP 85.36.184, 89.36.101, 89.121.1: Tooth-bearing dentaries.

RTMP 73.23.1, 80.16.439, 81.22.55, 81.22.55, 82.14.42, 82.19.106, 82.31.30, 85.43.24, 95.67.24: 10 isolated vertebrae.

RTMP 73.7.1, 91.23.47: Tibiae.

 

= cf. Palaeosaniwa canadensis HAMILTON, PAPARELLA, BELL, CAMPIONE, FANTI, LARSON, SISSONS, VAVREK, BALSAI & SULLIVAN, 2023

Locality: DC (Dinosaur-Chelonian) Bonebed, 55°4'53"N, 118°43'59"W, Grande Prairie County, Alberta Province, Canada.

Horizon: Unit 3, Wapiti Formation.

Biostratigraphy:

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

Material:

UALVP 59503: A right frontal.

Locality: Montana.

Horizon: Two Medicine Formation.

Biostratigraphy:

Age: Judithan Age, Campanian Stage, Senonian Subepoch, Gulf Epoch, Late Cretaceous.

Material:

MOR 792: Fragmetnary skull adn partial skeleton.

 

HOLROYD & HUTCHISON, 2002

Locality: V 86075, western North Dakota.

Horizon: Hell Creek Formation.

Biostratigraphy:

Age: Lancian Age, upper Maastrichtian Stage, uppermost Senonian Subepoch, Upper Upper Gulf Epoch, Late Cretaceous.

Material:

172405, 172427:

WHITMORE, 1988

Locality: SDSM Locality V851, Zerbst Locality, east of the Cheyenne River, Niobrara County, Wyoming.

Horizon: Lance Formation.

Biostratigraphy:

Age: Lancian age, upper Maastrichtian Stage, uppermost Senonian subepoch, Upper Gulf Epoch, Late Cretaceous.

SDSM 15102: 1 vertebra.

SDSM 15103: 1 vertebra.

 

= Megasaurus robustus GILMORE, 1928
Etymology:

Holotype: USNM 2901

Locality: "Peterson's Quarry," Lance Creek, Niobrara County, Wyoming.

Horizon: Lance Formation.

Biostratigraphy:

Age: Lancian age, upper Maastrichtian Stage, uppermost Senonian subepoch, Upper Gulf Epoch, Late Cretaceous.

Material: Anterior caudal vertebra.