A salp is a barrel-shaped tunicate (a marine invertebrate animal). It moves by contracting, thus pumping water through its gelatinous body. The salp strains the pumped water through its internal feeding filters. Salps are common in equatorial, temperate and cold seas, where they can be seen at the surface, singly or in long.
Salps have a complex lifecycle. Both portions of the lifecycle exist together in the seas. They look quite different but both are mostly transparent, tubular, gelatinous animals that are typically between 1 and 10 cm tall.