Genus: Tyrannotitan NOVAS, VALAIS, VICKERS-RICH & RICH, 2005
Etymology: Latin, tyrannus, "tyrant" and Latin, titan, "giant."

Species: chubutensis NOVAS, VALAIS, VICKERS-RICH & RICH, 2005
Etymology: In reference to the Chubut Province, Argentina, where the specimens were found.

Holotype: MPEF-PV 1156

Locailty: "La Juanita" farm, 28 km NE of Paso de Indios, Chubut Province, Patagonia, Argentina.

Horizon: Possibly Cerro Castano Member, Cerro Barcino Formation, Chubut Group.

Biostratigraphy:

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

Material: Partial dentaries, isolated teeth, dorsals 3-8 and 11-14, proximal caudal vertebra, isolated ribs and haemal arches, incomplete left scapulocoracoid, right humerus, right ulna, pubes, ischia, fragments of left ilium, almost complete left femora, fibula and metatarsal II.

Tyrannotitan chubutensis (modified from NOVAS, et al., 2005), Holotype: MPEF-PV 1156

Paratype:

MPEF-PV 1157: Jugals, right dentary, isolated teeth, atlas, cervical 97, dorsals 7?, 10 and 13, partially presered fused centra sacrals 1-5, isolated distal caudals, ribs, right femur, incomplete left metatarsal II, pedal phalanges 2.I, 2.II and 3.III.

Note: Approximately 7% larger than holotype.