1940  Altudoceras Ruzhentsev: 286.
     1951  Altudoceras.-Ruzhentsev: 141.
     1957  Pseudogastrioceras.- Treatise: L63.
     1960  Altudoceras.- Ruzhentsev: 221.
     1962  Altudoceras.- Osnovy: 385.
     1974  Altudoceras.-Ruzhentsev: 24.
     1977  Altudoceras.-Zhao & Zheng: 238.
     1985  Hengshanites Zhou: 196.
     1987  Altudoceras.-Zhou: 321,
      -----   Hengshanites.-Zhou: 328.
     2002  Altudoceras.-Leonova: S48.

Type species: Gastrioceras altudense Böse, 1917.

[Ruzhentsev, 1974, p.24:] Shell large, ranging from subophioconic to subdiscoconic. Whorls moderately involute.
Umbilicus ranging from moderately broad to moderately narrow (Du/D between 0.45 and 0.25), step-like in all stages.
Sculpture represented by well-developed, sometimes coarse lirae covering the entire outer surface of the shell from
one umbilical border to the other, and very fine lines. The number of lirae varies in the range 15-40 in different
species. Umbilical zone ornamented by tubercles (plicae) usually developed only in the early growth stages.
Constrictions present, disappearing with age. Lines and constrictions forming ventral sinus. Ventral lobe not very
broad (wl/hl~ 0.90), with practically parallel sides and fairly narrow lanceolate branches; median saddle of average
height (hs/hl ~ 0.50), fairly broad above, 2-peaked. This genus is sharply distinguished from Pseudogastrioceras and,
moreover, by many characters, namely:1) in Altudoceras the venter is broader, the whorls are less
involute and more slowly enlarging, the umbilicus is far wider (0.25 - 0.45 instead of 0.11 - 0.15) and invariably step-like,
and the cross section of the whorl is semi-elliptical, whereas in Pseudogastrioceras it is rather parabolic.
2) the sculpture is represented in both genera by fine, medium or coarse lirae, and the number of lirae is fully
commensurate, but in Altudoceras they cover the entire outer surface of the shell,
whereas in Pseudogastrioceras they cover only the peripheral parts, to the lateral lobe.
3) the sutures differ appreciably, especially in details: in Altudoceras the ventral lobe is not very broad (wl/hl~ 0.90), and
is practically parallel-sided, with fairly narrow branches, whereas in Pseudogastrioceras it is considerably broader (wl/hl>
1), with heavily diverging sides, even in juvenile shells, and with broad branches of different outline; the median saddles
also differ in outline.