''Romaniceras'' is a genus of

Upper Cretaceous The Late Cretaceous (100.5–66 Ma) is the younger of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''creta'', the ...

ammonite Ammonoids are a group of extinct marine mollusc animals in the subclass Ammonoidea of the class Cephalopoda. These molluscs, commonly referred to as ammonites, are more closely related to living coleoids (i.e., octopuses, squid and cuttlefish) ...

s in the

Acanthoceratidae Acanthoceratidae is an extinct family of acanthoceratoid cephalopods in the order Ammonitida, known from the Upper Cretaceous. The type genus is '' Acanthoceras''. Diagnosis Acanthoceratidae species are strongly tuberculate with at least umbil ...

subfamily

Euomphaloceratinae Euomphaloceratinae is a subfamily of Upper Cretaceous ammonites included in the Acanthoceratidae, characterized by generally evolute shells with quadrate whorl sections that are strongly ribbed. Sutures are ammonitic, but not overly complex. Gen ...

. The shell is rather evolute, whorl section circular to oval and ''Romaniceras'' differs from '' Acanthoceras'' in having 9 or 11 rows of tubercles, of which the ventrolateral may be clavate (i.e. elongate). The ribs of ''Romaniceras'' specimens are strong and fairly close spaced.W.J. Arkell ''et al.'', 1957. Mesozoic Ammonoidea; Treatise on Invertebrate Paleontology, Part L, Mollusca 4. Geological Society of America and University of Kansas Press.Spath, 1923

References

Cretaceous ammonites Acanthoceratidae Ammonitida genera Ammonites of Europe Cenomanian genus first appearances Turonian genus extinctions {{ammonitina-stub