Hydrolithon pachydermum

are eaten by

• Global Biotic Interactions: Calcinus tibicen (Herbst 1791)
• Global Biotic Interactions: Tegula lividomaculata (C. B. Adams 1845)
• Global Biotic Interactions: Pagurus brevidactylus (Stimpson 1859)
• Global Biotic Interactions: Alpheus cristulifrons Rathbun 1900
• Global Biotic Interactions: Synalpheus townsendi Coutière 1909

are preyed upon by

• Global Biotic Interactions: Calcinus tibicen (Herbst 1791)
• Global Biotic Interactions: Tripneustes ventricosus (Lamarck 1816)
• Global Biotic Interactions: Omalacantha antillensis (Rathbun 1920)
• Global Biotic Interactions: Epialtoides kingsleyi
• Global Biotic Interactions: Turbo castanea Gmelin 1791