REPRESENTATIVES OF the Prodromitidae are characterized by rel-
 atively large (up to 150 mm diarneter) lenticular conchs with acute
 ventral keels and complex multilobate sutural configurations.  The
 systematic position of the Prodromitidae has been the subject of
 considerable speculation (see Work et al., 1988 for review).  The
 nominate genus, Prodromites Smith and Weller, 1901 (type spe-
 cies, Goniatites gorbyi Miller, 1891), is not typical and represents
 the culmination of the lineage, showing characters which have led
 authors to refer it to both the Gephuroceratina (Ruzhencev, 1960,
 1962, 1965; Bogoslovsky, 1969; Ruzhencev md Bogoslovskaya,
 1978) and the Prolecanitina (Miller md Collinson, 1951; Weyer,
 1972; Furnish and Manger, 1973; Kullmann, 1981; Bartzsch und
 Weyer, 1988; Kullmann et al., 1991).  Discovery of an ancestral
 prodromitid genus, Eoprodromites Work, Mapes, and Thompson,
 1988 (type species, E. kinderhooki), in the Hannibal Shale of
 northeastern Missouri provided clarification on the derivation of
 Prodromites and provided a link to yet a third enigmatic genus,
 Qiannanites Ruan, 1981 (type species, Q. acutus).  Work et al.
 (1988) concluded that the Prodromitidae were prolecanitid oft-
 shoots that appeared in the early Tournaisian with Qiannanites,
 progressed through Eoprodromites, und climaxed with Prodrom-
 ites early in the late Tournaisian.  Although aspects of sutural on-
 togenesis, conch morphology, and stratigraphic distribution unite
 these genera, subsequently obtained specimens of Eoprodromites
 kinderhooki provide additional sutural md morphological details
 (Figs. 1, 2) that support derivation from the prionoceratacean sub-
 family Pseudarietinae Bartzsch and Weyer, 1987, as more re-
 cently suggested by Becker (1993a, p. 471).