Siphonosoma  

Genus Siphonosoma Spengel, 1912

(From Cutler, 1994)

Large specimens with trunk longer than 50 mm in adults.

Introvert shorter than the trunk, with conical papillae and sometimes hooks, arranged in rings.

Coelomic extension in the body wall is small, irregular and saclike.

Anastomosed longitudinal muscles, sometimes divided in distinct bands.

Tentacles arranged around the mouth.

Two pairs of retractor muscles.

Contractile vessels, with or without villi.

Spindle muscle attached posteriorly.

A pair of nephridia.

Type species

Phascolosoma australe Keferstein, 1865