Ammonite habitats in the Early Tithonian of Western Tethys

Cccca, F. 1992 07 15: Ammonite habitats in the Early Tithonian of Western Tethys.
Habitats of Early Tithonian ammonites of Western Tethys are inferred from analysis of faunal spectra, functional morphology. facies characteristics and palaeogeography. Phylloceratina and Lytoceratina are included in a pelagic group characterized by taxa which could reach bathyal depths. This group is very abundant and dominant in some localities. A neritic nektobenthic group, relatively abundant in the Cmbria-Marche Apennines only. is composed of taxa characterired by species bearing simple sutures (some Simoceratidae and Pseudolissoceras ). probably living at shallower depth. The habitat of Haplploceras and some Oppeliidae. is interpreted to be close to the shelf margin/continental slope. Perisphinctids. Aspidoceratidae and some other Oppeliidae are provisionally included in an 'indeterminate' group including deep and shallow taxa. Quantitative studies of assemblage composition and comparison of faunal spectra successions from different pelagic regions allow the characterization of different pelagic environments. Bathymetric hypotheses by means of ammonites are discussed. Z Ammonoidea. habitats. facies, faunal spectra. Jurassic, Tithonian. Tethys .