Family Arcidae is a group of marine bivalve mollusks commonly known as ark clams. These clams are found in shallow marine waters and are characterized by their elongated, triangular shells. These shells are often used for decoration and are popular among collectors. Other synonymous terms for Family Arcidae include ark shells, wedge shells, and duckbill clams. These clams are filter feeders, using their gills to extract food from water. They are also important food sources for fish and other aquatic animals. Due to their unique shape and colorful shells, ark clams are often used in decorative crafts and jewelry.