Polymastia invaginata Kirkpatrick 1907

are eaten by

• Global Biotic Interactions: Doris kerguelenensis (Bergh 1884)
• Global Biotic Interactions: Odontaster meridionalis (E. A. Smith 1876)
• Global Biotic Interactions: Acodontaster conspicuus (Koehler 1920)
• Global Biotic Interactions: Acodontaster hodgsoni (Bell 1908)
• Global Biotic Interactions: Perknaster fuscus

are preyed upon by

• Global Biotic Interactions: Odontaster meridionalis (E. A. Smith 1876)
• Global Biotic Interactions: Acodontaster conspicuus (Koehler 1920)
• Global Biotic Interactions: Pentanymphon antarcticum Hodgson 1904
• Global Biotic Interactions: Ammothea carolinensis Leach 1814
• Global Biotic Interactions: Echiniphimedia hodgsoni (Walker 1906)