Synonyms: Phascolosoma diaphanes (heterotypic); Phascolosoma duplicigranulatum; Phascolosoma evisceratum; Phascolosoma extortum; Phascolosoma hainanicum; Phascolosoma horsti; Phascolosoma lacteum; Phascolosoma minutum (heterotypic); Phascolosoma nigrescens; Phascolosoma planispinosum; Phascolosoma plicatum; Phascolosoma puntarena; Phascolosoma spengeli; Phascolosoma uncatum; Phascolosoma varians; Phascolosomum puntarenae; Phymosoma diaphanes; Phymosoma duplicigranulatum; Phymosoma lacteum; Phymosoma nigrescens; Phymosoma spengeli; Phymosoma varians; Physcosoma agassizii var. puntarenae; Physcosoma duplicigranulatum; Physcosoma evisceratum; Physcosoma extortum; Physcosoma horsti; Physcosoma lacteum; Physcosoma minutum; Physcosoma nigrescens; Physcosoma spengeli; Physcosoma varians; Sipunculus nigrescens; Sipunculus plicatus; Sipunculus puntarenae; Sipunculus varians