Genus: Eternauta CAMPOS, FERNANDEZ, HERRERA & TALEVI 2025
Etymology: Latin,aeternus, "eternal" and Latin, nauta, "salior"; In reference to El Eternauta (1957) created by Hector Oesterheld and Francisco Solano Lopez, a seminal Argentine science ficition comic whos protognist introduces himself as "a navigator of time, a traveller of eternity, and a pilgrim of the centuries."

Species: patagonica CAMPOS, FERNANDEZ, HERRERA & TALEVI 2025
Etymology: In reference to the Patagonia region, where the holotype was discovered. Together, the name translates to 'The one who navigates eternallin in Patagonia' relecting both its geographic oprigin and the enduring palaeontological legacy of marine reptiles in the region.

Holotype: MLP-PV 85-I-15-1

Locality: Chacay Melehue, 37°17'20"S, 70°30'45"W, Neuquen Province, Patagonia, Argentina.

Horizon: Vaca Muerta Formation, Mendoza Group.Formation.

Biostratigraphy:

Age: Tithonian Stage, Late Malm Epoch, Late Jurassic.

Material: An almost complete skull, teeth, fragmentary rib and right forelimb.