Abstract.  The characteristic and common mid-Carboniferous ammonoid Cravenoceras Bisat,
 1930 has been used to formally define the base of the Namurian Series in western Europe
 since 1958.  This generalized form possesses a smooth, moderately umbilicate shell marked
 by fine growth lamellae, and has a simple 8-lobed suture.  By the 1970"s, Cravenoceras had
 come to include a wide range of rnorphologies and suture variations.  In 1971, V.E.Ruzhencev
 and M.F.Bogoslovskaya refined the concept of the genus to be more allied with the type species,
 C. malhamense (Bisat, 1924), and restricted it to forms with sutures that possessed relatively
 narrow ventral lobes and prongs and a shallow median saddle.  Otherwise similar forms, but
 with wide ventral lobes and a deep median saddle, were referred to the genus Glaphyrites
 Ruzhencev, 1936.  Although they quantifed these characters in a way that permitted objective
 definition of the two genera, the taxonomy became clouded by the recognition of a series of
 related genera, including Richardsonites, Fayettevillea, Stenoglaphyrites, Rhadinites, Emstites,
 and Zidadarites.  We review the current status of these genera and revise the concept of
 Glaphyrites to more closely conform to its Upper Carboniferous type species, G. modestus
 (Böse, 1917), and name a new species of Cravenoceras, C. bogoslovskayae n. sp., from the
 Goddard Shale (E2) of Oklahorna.  We recommend that Stenoglaphyrites be restricted to
 involute forms such as the type species, S. involutus (Gordon, 1965), and suggest that
 recognition of the genera Emstites and Zidadarites is problematic.