1934  Homoceratinae Spath: 15.
     1960  Homoceratidae.- Ruzhentsev: 211.
     1962  Homoceratidae.- Osnovy: 375.
     1971  Homoceratidae.- Ruzhentsev & Bogoslovskaya: 17.

Superfam. Gastriocerataceae:

A: Conch form variable, with broad whorl section and umbilicus.
Early whorls commonly evolute.
B-D: Shell smooth or sculptured. Transverse striae and
constrictions, if present, with ventral sinus or salient.
G: Prongs of ventral lobe relatively wide and pouched, its sides
being curved or straight, but usually not divergent; median
saddle half as high or higher than entire ventral lobe. First
lateral saddle rounded or subacute. Sutural formulae: [Germ.]
(E1EmE1)ALUI, [Russ.] (V1V1)LU:ID.

Family Homoceratidae SPATH, 1934:

A:   Conch form discoidal to globose, moderately involute.
Umbilicus moderately wide to narrow. Tendency towards oxycone
venter.
B-C: More or less prominent transversal ornamentation frequently
present; course of growth striae or lamellae variable, but always
forming ventral sinus. Spiral ornamentation rare and mostly
restricted to umbilical shoulder. Umbilical tubercles in advanced
forms.
G:   Ventral lobe relatively wide, with sigmoidal or roundedly
diverging sides; median saddle fairly high. First lateral saddle
broadly rounded. Adventitious lobe pointed, mostly with straight
sides, rarely bell-shaped or rounded.

Subfamily Homoceratinae SPATH, 1934:

A:   Commonly early whorls evolute, with wide and low section and
sharp umbilical shoulder ("calyx" stage).
B:   Transversal ornamentation rarely coarse, usually lamellate,
frequently dichotomizing, forming a ventral sinus on adult
stages. No reticulate ornamentation.


Subfamily Decoritinae RUZHENTSEV & BOGOSLOVSKAIA, 1975:

A:   Conch form like Homoceratinae, but no "calyx" stage with
sharp umbilical shoulder on early whorls.
B:   Sculpture consisting of dichotomous or polyschizotomous ribs
forming shallow ventrolateral salient and ventral sinus.
F:   Reticulate ornamentation in advanced forms.
G:   Ventral lobe relatively narrow, median saddle reaching
almost two third of height of entire ventral lobe.

[Ruzhentsev & Bogoslovskaia, 1971, p. 18]: Shell of young
individuals ranging from spheroconic or cadiconic to pachyconic,
adult shell mainly oxyconic, less frequently pachyconic or
dubdiscoconic. Whorls from moderately to completely involute,
even overhanging in some stages. Umbilicus from moderately broad
to very narrow. Sculpture transverse, represented by fairly
coarse lamellae or costellae, frequently dichotomizing and
forming a considerable ventral sinus in adult shells. Lirae very
occasionally, but only around umbilicus. Weak umbilical tubercles
sometimes developed on early and middle whorls, and also
intraventral ridges (from 1 to 3). Ventral lobe moderately
developed: wl/hl approximately 1, sometimes greater; median
saddle fairly high.