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This heteromorphic species is characterized by an open plain spiral shape with slightly rursiradiate ribs and 3 sets of tubercles; 2 sets of ventrolateral tubercles, and 1 set of ventral tubercles. The whorl section is compressed and does not have constrictions in United States specimens but does have constrictions in many European specimens. The distance between ribs is roughly the same as the width of a rib. As far as I know, there are only two species reported for this genus, with the other being Phlycticrioceras rude from the late Santonian of France (Kennedy 1995). P. trinodosum is the on