1919  Prothalassoceras B÷se: 102.
     1948  Prothalassoceras.- Maximova: 23.
 ?  1957  Thalassoceras Gemmellaro, 1887.- Treatise: 68.
     1960  Prothalassoceras.- Ruzhentsev: 206.
     1962  Prothalassoceras.- Osnovy: 370.
     1971  Prothalassoceras.- Nassichuk: 1005.
     2002  Prothalassoceras.-Leonova: S41,
     -----   Allothalassoceras Leonova: S41.

Type species: Prothalassoceras welleri Böse, 1919, p.104 [SD Plummer & Scott, 1937, p.353].

A:   Conch form  subdiscoidal to subglobular, with very narrow or closed umbilicus.
G:   Suture-line almost digitate, but denticulation of lobes not reaching saddles. Adventitious lobe narrower than
       prongs of ventral lobe.

Fig. TAX5217 A: Aristoceras serum, B: P. jaikense, C: P. notabile, D: P. inflatum, E: P. bashkiricum, F-G: P. serratum, H:
P. biforme (sutures, from Bogoslovskaia et al., 1995, fig.10).