The large branchiopods are approximately 500 species of primitive crustaceans found in temporary and saline inland aquatic habitats. Together with the Cladocera, they form the crustacean class Branchiopoda. Most are planktonic or semibenthic, and are used as indicators of aquatic ecosystem health, which ultimately reflects on land-use practices and management. Several species are protected under environmental law, and some species are economically important. As obligate aquatic macroinvertebrates, large branchiopods are important links in the aquatic food chain of ephemeral wetlands.