Gibbs, P.E. (1977). British sipunculans: keys and notes for the identification of the species. <i>Synopses of the British fauna (new series)</i>, 12. Academic Press: London, UK. ISBN 0-12-282050-9. 35 pp. (look up in IMIS) [details]
Around south-west England, this species matures at a small size (<10 mm in length).