Bivalvia

class of molluscs Bivalvia (Bivalvia) is a class of organisms united by key anatomical and physiological traits. It contains 17 orders with 234 known species. Key order groups include Adapedonta, Arcida, Cardiida, Carditida, Galeommatida, and Gastrochaenida. Among its members, 34 species are currently classified as threatened (Critically Endangered, Endangered, or Vulnerable). It belongs to Mollusks (Mollusca).