1958  Tympanoceras Ruzhentsev: 295.
     1960  Tympanoceras.- Ruzhentsev: 212.
     1962  Tympanoceras.- Osnovy: 376.
     1971  Tympanoceras.- Ruzhentsev & Bogoslovskaia: 267.

Type species: Tympanoceras trisulcatum Ruzhentsev, 1958, p.295 [OD].
= Collectoceras RUZHENTSEV & BOGOSLOVSKAIA, 1971, p.266, type C. dombarense, p.266; OD (subj.);
= Aravanites (LACHAROV) ZAKHAROV, 1971, p.93, type A. kirgizstanicus ZAKHAROV, 1971, p.93; OD (subj.].

[Ruzhentsev & Bogoslovskaia, 1971, p.267: Medium sized conch, from subsphaericone to
pachycone and even discoidal.  Whorls moderately involute.  Umbilicus of medium size or
moderately wide.  Sculpture is radial and spiral, sometimes expressed sharply, sometimes
almost disappearing.  Two to four wide and deep constrictions per revolution are present.  
The back side of the constrictions is sloped, the fore side is sheer.  They begin at the
umbilical seam, sharply directed backwards, form a tight, asymmetric sinus at the
pre-umbilical zone and cross the ventral zone almost straight.  The ventral lobe is
narrow (lobe width/height approx.  0.60), sides weakly parting in early species and
almost parallel, at the top even somewhat drawn together, in later species.  Height of
the median saddle is half of the whole lobe.]  

A:   Conch form subdiscoidal to discoidal, moderately involute, with wide umbilicus; height of aperture small.
D:   One to four constrictions per whorl, orad concave on flanks, crossing venter straight.
G:   Ventral lobe rather narrow, with relatively low median saddle; first lateral saddle broadly rounded. Adventitious lobe
relatively narrow, pointed, with straight sides.

[Collectoceras is distinguished by presence of only one single deep constriction, regarded herein as a specific rather than generic character. Aravanites is based on two poorly preserved specimens with fairly involute conch shape].