Due to the abundance and sensitivity of the mysid shrimp, Americamysis bahia, to environmental changes, they are essential to the health of many benthic and pelagic ecosystems.  Like many planktonic crustaceans, they are also agile, efficient swimmers. Propulsion is achieved via metachronal paddling of either the thoracopods (i.e., the appendages near their mouth region) or both thoracopods and pleopod appendages, which are located along their abdomen. Mysid shrimp, A. bahia, are more efficient metachronal swimmers than other species, which makes them an attractive candidate for investigating propulsion hydrodynamics. In this study, a high-speed tomographic particle image velocimetry (PIV) system was used to measure the time-resolved 3D velocity field around free-swimming mysid shrimp and its wake for both thoracopod and thoracopod+pleopod propulsion. When A. bahia swim with both pleopods and thoracopods, it produces a robust, well-developed 3D multi-jet system in its wake that is not seen when using only its thoracopods. The data provide novel insight into bio-locomotion of free-swimming mysid shrimp and propulsion flow characteristics in the intermediate Reynolds number regime, in which many aquatic species reside.