Chapter 32 - Class Malacostraca, Order Decapoda

Abstract

The order Decapoda includes about 15,000 species of shrimps, crayfish, lobsters, and crabs that belong to four out of the 10 infraorders of Malacostracan crustaceans. This chapter focuses on the approximately 3,000 species of freshwater decapods worldwide that includes over 760 species of caridean freshwater shrimps, 644 species of freshwater crayfish (Astacidea), 1,450 species of brachyuran freshwater crabs, and 75 species of anomuran freshwater crabs (aeglids, porcelain crabs, and hermit crabs). The chapter discusses the latest studies on their evolutionary relationships and higher classification, and covers morphological, physiological, and behavioral diversity, as well as ecological importance and life history. The range of freshwater habitats around the world where these decapods are found includes both surface waters and subterranean burrows and caves. Crayfish and anomuran freshwater crabs are predominantly found in temperate waters at mid- and low latitudes, brachyuran freshwater crabs are restricted to warm water habitats, while the freshwater shrimps occur in both tropical and temperate fresh waters. The chapter ends with a discussion of how to collect, culture, and preserve freshwater decapods.