Typically rather evolute with round, oval or quadrate whorl section, ventral keel, strong ribs, and at least umbilical tubercles. Many genera with spiral striations or notches.
Subfamily: MOJSISOVICZIINAE Hyatt, 1903
Derivatives of Brancoceratinae, in which the keel tends to become stabilized as an adult feature and the ribs begin to differentiate. In some forms the keel appears early in ontogeny and is then lost; in others it only appears late. Apparently, there are two main stocks (both derived from Mojsisoviczia or one from the other): one compressed and high-whorled, which left no descendants, and the other more evolute, with round or square whorl section, which by acquisition of tubercles led to Mortoniceratinae. The boundary between subfamilies is arbitrarily taken at the point when large umbilical and ventrolateral tubercles are stabilised in the adult.


Genus: Dipoloceroides BREISTROFFER, 1947
Dipoloceroides spinulosum, (Spath 1929)


Genus: ?Mojsisoviczia STEINMANN, 1881
Type species: Ammonites delaruei d'ORBIGNY, 1841
? Mojsisoviczia sp (inner whorls)


Genus: Oxytropidoceras STIELER, 1920
Type species: Ammonites roissyanus d'ORBIGNY, 1841
Moderately to compressed and high-whorled, with high keel; ribs single to branching, narrow and high, rounded or flat, with or without tubercles; keel may appear well before ribs; ribs may be effaced later. Suture generally with oblique outer slope on first lateral saddle.
Subgenus: Oxytropidoceras (Oxytropidoceras)
Moderately to very high-whorled and compressed; rather involute; ribs coarse to fine, high and narrow to flat, mostly branching at various levels, and without tubercles.
Oxytropidoceras (Oxytropidoceras) roissyanum (d'Orbigny, 1841)
Subgenus: Oxytropidoceras (Mirapelia) COOPER, 1982
Ammonites mirapelianum d'ORBIGNY, 1850
Whorl section varying from only a little higher to wide to moderately compressed; ribs single, costate to rather fine, and markedly flattened and broadened on shoulders.
Oxytropidoceras (Mirapelia) evansi,(Spath 1929)


Genus: Dipoloceras HYATT, 1900
Type species: Ammonites cristatus BRONGNIART, 1822
Rather evolute; whorl section round or depressed; keel prominent, commonly below level of ventrolateral ends of ribs; ribs dense to distant, rounded to sharp, typically a mixture of single and branched, the latter flared at point of branching; umbilical and ventrolateral tubercles absent or insignificant. Sutures plump, broad, finely indented saddles.
Subgenus: Dipoloceras (Dipoloceras)
Dipoloceras (Dipoloceras) cornutum, (Pictet 1847)
Dipoloceras (Dipoloceras) equicostatum, Spath 1929
Dipoloceras (Dipoloceras) cristatum (Brongniart 1822)
Dipoloceras (Dipoloceras) fredericksburgense Gayle Scott, 1928
Dipoloceras (Dipoloceras) pseudaon, Spath 1929
Dipoloceras (Dipoloceras) bouchardianum (d'Orbigny 1841) var alticarinata Spath 1929


Wright C.W. 1996. Treatise on Invertebrate Paleontology; Part L MOLLUSCS 4 Revised (Volume 4: Cretaceous Ammonoidea)


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