THE SUTURE LINE PATTERNS IN OLCOSTEPHANIDAE AND SPITICERATIDAE, AMMONITES OF THE UPPER JURASSIC-LOWER CRETACEOUS: SYSTEMATIC CONSIDERATIONS

The systematic classification of the ammonites in the family Olcostephanidae here proposed is in according to different sutural line patterns. The saddle S1 is bifurcated in the Family Spiticeratidae Spath, 1924, and trifurcated in the Family Olcostephanidae Haug, 1910. New taxa are proposed based on the suture line and their ornamentation, Groebericeratinae n. subfam., Saynoceratinae n. subfam., Garcitinae n. subfam., Kurdistanites n. gen., Peruvites n. gen., Spiticeras (Djanelidzeites) n. subgen. Taraisitinae Cantu-Chapa, 1966. All of them are from the Upper Tithonian-Lower Hauterivian.