Genus: Tiamat PEREIRA, BANDEIRA, VIDAL, RIBEIRO, dos A. CANDEIRO & BERGQVIST, 2024
Etymology: 'Tiamat' is a goddess from Sumerian and Babylonian mythologies, often described as a dragon or a great serpent. Tiamat is also identified as the mother of dragons (and other mythical creatures) and all gods, alluding to the basal positioning of this new species into the group to which belong to the largest animals that have ever walked the Earth.

Species: valdecii PEREIRA, BANDEIRA, VIDAL, RIBEIRO, dos A. CANDEIRO & BERGQVIST, 2024
Etymology: In honor of Prof. Dr. Valdeci dos Santos Junior of Universidade Estadual do Rio Grande do Northe, for the discovery of the fossil site and for his fundamental support during the fieldwork.

Holotype: UFRJ-DG 636-R, 638-R, 606-R, 635-R, 591-R, 527-R, 704-R, 574-R

Locality: Potigual Basin, Ceara State, north-east Brazil.

Horizon: Acu Formation.

Biostratigraphy:

Age: Albian Stage, Middle Gallic Subep9och, Late Early Cretaceous Epoch, Late Early Cretaceous-Cenomanian Stage, Late Middle Gallic Subepoch, early Gulf Epoch, Middle Cretaceous.

Material:

Breakdown as follows:

UFRJ-DG 636-R, 638-R, 606-R: Anterior caudal vertebrae.

UFRJ-DG 635-R, 591-R, 527-R, 704-R: Middle caudal vertebrae.

UFRJ-DG 574-R: Partial neural arch.