Genus: Tangvayosaurus ALLAIN, TAQUET, BATTAIL, DEJAX, RICHIR, VERAN, LIMON-DUPARCMEUR, VACANT, MATEUS, SAYARATH, KEHENTHAVONG AND PHOUYAVONG, 1999
Etymology: In reference to the type locality, Tang Vay, Khon Kaen Province, northeastern Thailand and Greek, sauros, “lizard”: Tang Vay Lizard.


Species: hoffetti ALLAIN, TAQUET, BATTAIL, DEJAX, RICHIR, VERAN, LIMON-DUPARCMEUR, VACANT, MATEUS, SAYARATH, KEHENTHAVONG AND PHOUYAVONG, 1999
Etymology: In honor of Josue-Heilmann Hoffett, member of the Service geologique de l’Indochine, who discovered the first Australasian dinosaurs.

Holotype: TV4-1 to TV4-36

Locality: TV 4, Tang Vay, Savannaker Province, R.D. P. Lao, Laos.

Horizon: Gres superieurs Formation.

Biostratigraphy:

Age: Aptian-Albian Stage, Middle Gallic Subepoch, Upper Early Cretaceous Epoch, Early Cretaceous.

Material: 38 caudal vertebrae, chevrons, metacarpal, cervical vertebra and the distal end of the femur, tibia, fibula, astragalus, 3 metatarsals and 9 pedal phalanges of the left hindlimb.

Referred material:

Locality: TV 2, Tang Vay, Savannaker Province, R.D. P. Lao, Laos.

Horizon: Gres superieurs Formation.

Biostratigraphy:

Age: Aptian-Albian Stage, Middle Gallic Subepoch, Upper Early Cretaceous Epoch, Early Cretaceous.

Material:

TV2-40: Left fibula.

TV2-39: Left tibia.

TV2-6: Caudal vertebra.