Genus Palaemon is a group of freshwater and marine shrimps that are commonly found in tropical and subtropical regions. This genus has several synonyms that are used to refer to it, including Leander, Palaemonetes, and Macrobrachium. Leander was once considered a separate genus, but it is now considered a synonym for Palaemon because both genera have similar characteristics and belong to the same family. Palaemonetes is another synonym that is commonly used for freshwater species within the genus. Macrobrachium, on the other hand, is a synonym used for larger species of Palaemon, especially those found in freshwater habitats. Regardless of the synonym used, the species within the genus Palaemon are fascinating and important components of aquatic ecosystems.