As mentioned in a previous post, the mollusk shells from the Po Plain can be categorized into groups based on the depositional environment in which the species occurred. These distinct communities can be used to study the sequence stratigraphy of the Po Plain. One of the distinct groups of shells, or facies, is the lagoon.

The lagoon includes the inner lagoon and outer lagoon. Some common mollusk species from the inner lagoon include the very small gastropods, Bithynia tentaculata and Ecrobia ventrosa. Some common species from the outer lagoon include the bivalve species, Cerastoderma glaucum and Loripes lucinalis. When these groups of shells, which tend to be from species that can live in nutrient-poor environments, are found in a sediment core from Po Plain, this is an indication of a lagoon environment where that core was taken at the time that those shells occurred.

Here are representative images of these common lagoon species, courtesy of Daniele Scarponi, University of Bologna, Italy.