👉 Petrothrincus is a genus of small, low-lying, crustacean mollusk in the family Trichobatidae, which are commonly found on rocky shores and near freshwater bodies. These mollusks have a hard, tough shell made from calcium carbonate. Petrothrincus is characterized by its large eyes that can be very sensitive to light, often having red or purple coloration due to their pigment. They feed primarily on small crustaceans and other inverte