1884  Gastrioceras Hyatt: 327.
pt. 1889  Gastrioceras.- Karpinsky: 45.
pt. 1897  Gastrioceras.- Foord & Crick: 226.
     1902  Glyphioceras.- Frech: 84.
pt. 1903  Gastrioceras.- Smith: 82.
     1914  Gastrioceras.- Wedekind: 13.
     1915  Gastrioceras.- Girty: 248.
     1917  Gastrioceras.- Böse: 82.
     1918  Gastrioceras.- Wedekind: 158.
     1924  Gastrioceras.- Bisat: 119.
     1925  Gastrioceras.- Schmidt: 590.
     1927  Gastrioceras.- Smith: 27.
     1927  Gastrioceras.- Diener: 66.
     1929  Gastrioceras.- Schmidt: 72.
     1936  Gastrioceras.- Ruzhentsev: 1079.
     1937  Branneroceras Plummer & Scott: 218,
     1937  Gastrioceras.- Plummer & Scott: 235.
     1938  Agastrioceras.- Schmidt: 120.
     1939  Gastrioceras.- Librovich: 135.
     1941  Gastrioceras.- Delepine: 87.
pt. 1941  Gastrioceras.- Librovich: 151.
     1945  Agastrioceras.- Dorsman: 73.
      -----    Gastrioceras.- Dorsman:70.
     1952  Gastrioceras.- Termier: 7.
     1956  Gastrioceras.- ICZN, Opinion 420 (Official list: 138,  No.1007).
     1957  Gastrioceras.- Treatise: L61.
     1959  Agastrioceras.- Patteisky: 37.
     1960  Gastrioceras.- Ruzhentsev: 217.
     1962  Gastrioceras.- Osnovy: 381.
     1962  Gastrioceras (Gastrioceras).- Kullmann: 85.
 ?  1965  Gastrioceras (Gastrioceras).- Gordon: 251 - 253.
     1965  Gastrioceras.- Patteisky: 17.
     1975  Gastrioceras.- Nassichuk: 124.
     1968  Gastrioceras.- McCaleb: 40.
     1982  Gastrioceras.- Nishida & Kyuma: 20.
     1997  Gastrioceras.- Mapes et al.: 210.

Type species: Ammonites Listeri Sowerby, 1812, p. 97, pl.455  [ICZN Opinion 420, 1956].

[*Ammonites listeri SOWERBY, 1812, p.97 (non MARTIN, 1809, pl.35, fig.3, see Opinion 420 ICZN 1954, p.239); SD FOORD & CRICK, 1897, p.226].

C:   Umbilical shoulder ornamented with nodes which are elongated transversely; in some species rather strong ribs.
F:   Longitudinal lirae usually very faint or absent.

[Mapes et al., 1997, p.210: Conch subdiscoidal to subglobose, umbilicus moderate to wide; umbilical shoulder nodose. Ornament ranging from simple transverse lirae to reticulate pattern in some species. Suture characteristically having a high median saddle between attenuated prongs of ventral lobe; lateral lobe generally nearly symmetrical and becoming attenuated on mature specimens.]
 
[Nassichuk, 1975, p.124: Gastrioceras displays considerable variation in conch form but is typically broad (W/D between 65 and 70 per cent) and widely umbilicate (U/D approximately 50 per cent); on some species W/D is close to 50 and U/D is close to 30 per cent. Tubercles persists on the umbilical shoulder of the type species to full maturity; transverse striae are coarse and widely spaced and form shallow ventral and lateral sinuses. In the type species, longitudinal lirae are confined to the umbilical shoulders where a reticulate pattern is developed. On some species longitudinal lirae persist across the venter at least during early ontogeny and in others both longitudinal lirae and transverse striae are absent from the venter.
  On the external suture, prongs of the ventral lobe are separated by a low ventral saddle that is about half the height of the broad and evenly rounded first lateral saddle. Ventral prongs are generally twice as wide as the first lateral lobe and three times as wide as the first lateral saddle. The first lateral lobe is variously lanceolate or V-shaped and is about half the width of the lateral saddle].