<==o Sipuncula Rafinesque, 1814 [Sipunculida Rafinesque, 1814; Sifunculacei Delle Chiaje 1823; Gephyrea de Quatrefage 1847; Sipunculacea Hatschek 1881; Podaxonia Lankester 1885; Prosopygia Lang 1888; Sipunculoidea Sedgwick 1898] (ruiskumadot)
   |--o Sipunculidea Rafinesque, 1814
   |  |--o Sipunculiformes Gibbs & Cutler, 1985
   |  |  `-- Sipunculidae Rafinesque 1814
   |  `--o Golfingiiformes Cutler & Gibbs, 1985
   |     |-- Golfingiidae Stephen & Edmonds, 1972
   |     |-- Phascolionidae Cutler & Gibbs, 1985 [Phascoliidae Cutler & Gibbs, 1985]
   |     `-- Themsitidae Cutler & Gibbs, 1985
   `--o Phascolosomatidea Cutler & Gibbs, 1985 [Phascolosomida Cutler & Gibbs, 1985]
      |--o Phascolosomatiformes Cutler & Gibbs, 1985 [Phascolosomaformes Cutler & Gibbs, 1985]
      |  `-- Phascolosomatidae Stephen & Edmonds, 1972
      `--o Aspidosiphoniformes Cutler & Gibbs, 1985
         `-- Aspidosiphonidae Baird, 1868

Reference(s):

• http://www.mcz.harvard.edu/Departments/InvertZoo/as.fldr/cutler/siptaxa.htm

Special thanks to:

Jos H. M. Dols, for gathering additional information and species of these animals.