Genus: Lambeosaurus PARKS, 1923
Etymology: In honor of Lawrence Morris Lambe (1863-1919), Canadian Paleontologist.

Species: ? laticaudus MORRIS, 1981
Etymology: Latin, latus, “broad, wide”, and Latin, caudal, “tail”.

Holotype: IGM 5843 (formerly LACM 17715)

Locality: LACM loc. 66168, north of Arroyo Del Rosario, Approximate Lat. 30'10"N, Long. 115'40"W, El Rosario, Baja California Del Norte, Baja California State, Mexico.

Horizon: "El Diesacado member" of the "El Gallo Formation".

Biostratigraphy:

Age: Maastrichtian Stage, Uppermost Senonian Subepoch, Uppermost Gulf Epoch, Late Cretaceous.

Material:

IGM 5849 (formerly LACM 17711): Pathologic left tibia.