Nothosaurus jagisteus was named by Rieppel (2001) [Jugal short, small and splint like, intercalated between maxilla and postorbital but excluded from orbital margin; anterior tip of jugal located in front of the level of the posterior margin of the orbit; postorbital and maxilla in contact with each other behind jugal; maxilla curving around the posteroventral corner of the orbit; squamosal extending anteriorly to a level in front of the posterior end of the maxilla, but separated from the maxilla by the postorbital; four fangs in a mandibular symphysis with a length to width ratio close to 1.5; retroarticular process elongate, with a distinct ventrolateral facet for the insertion of the superficial pterygoideus muscle; "saw-cut" rugosities at the dorsal margin of the neural arches in the cervical and dorsal regions; neural spines of dorsal vertebrae of intermediate height.]. Its type specimen is SMNS 56618, a partial skeleton (partial articulated skeleton), and it is a 3D body fossil. Its type locality is Nothosaurus jagisteus-type locality, which is in a Ladinian marine horizon in the Meissner Formation of Germany.