Published online by Cambridge University Press: 01 May 2009
Litophragmatoceras incomptum gen. et sp.nov. is a small dimorphic planulate ammonite from the Upper Cenomanian Metoicoceras mosbyense Zone of Arizona in which microconchs are adult at as little as 5 mm diameter and macroconchs at 23 mm diameter or less. The quinquelobate suture is very simple, with entire lobes and saddles. It is distinct from all contemporaneous ammonites and is referred, with no great certainty, to the otherwise exclusively Upper Albian and Lower Cenomanian Flickiinae Adkins, 1928.