<p><strong>Neritidae</strong>, common name the <strong>nerites</strong>, is a taxonomic family of small to medium-sized saltwater and freshwater snails which have a gill and a distinctive operculum, marine,brackish water and freshwater gastropod mollusks in the order Neritoida.</p> <p>The family Neritidae includes marine genera such as Nerita, marine and freshwater genera such as Neritina, and freshwater and brackish water genera such as Theodoxs a sea god in Greek mythology.</p>