Mollusc suborders

Ammonitina comprises a diverse suborder of ammonite cephalopods that lived during the Jurassic and Cretaceous periods of the Mesozoic Era. They are excellent index fossils, and it is often possible to link the rock layer in which they are found to specific geological time periods.

suborder of gastropods

The Ancyloceratina were a diverse suborder of ammonite most closely related to the ammonites of order Lytoceratina. They evolved during the Late Jurassic but were not very common until the Cretaceous period, when they rapidly diversified and became one of the most distinctive components of Cretaceous marine faunas. They have been recorded from every continent and many are used as zonal or index fossils. The most distinctive feature of the majority of the Ancyloceratina is the tendency for most of them to have shells that are not regular spirals like most other ammonites. These irregularly-coil

The Corbiculacea are a suborder of freshwater clams, aquatic bivalve molluscs in the order Venerida.

Acanthochitonina is a of polyplacophoran mollusc comprising both fossil and extant species.

Pectinina is a taxonomic grouping of saltwater clams, a suborder within the order Pectinida of marine bivalve molluscs.

Chitonina is a suborder of polyplacophoran mollusc belonging to the order Chitonida.

Lepidopleurina is a suborder of polyplacophoran molluscs. It includes both extinct and extant species.