Salps: Thaliacea

Physical characteristics: Salps in the asexual stage are about 0.5 inches (12 millimeters) long and have a pair of tentacles at their hind end. Salps in the sexual stage are about 0.2 inches (6 millimeters) long. The body covering is thick and has five muscle bands.

Geographic range: Salps live all over the world in warm to cool seas. Because they are found throughout the world, no distribution map is provided.

Habitat: Salps usually live in surface waters.

Diet: Salps eat plant plankton.

Behavior and reproduction: Salps swim actively through the water by contracting their muscles. Salps are one of the fastest growing many-celled animals. Their body length more than doubles within an hour. Salps in the asexual stage produce a tail on which bud rows of the sexual stage stay connected to one another, forming chains several feet (meters) long. Fertilized salp eggs develop directly into the asexual stage. New generations of salps are produced in as fast as a few days, resulting in huge swarms covering hundreds of square miles (kilometers) of open ocean.

Salps and people: Salps have no known importance to people.

Salps are one of the fastest growing many-celled animals. Their body length more than doubles within an hour. (Illustration by Emily Damstra. Reproduced by permission.)

Conservation status: Salps are not considered threatened or endangered. ∎