An association of a colonial host coral and its inhabitants is found in the Leithakalk (corallinacean detritic limestone, Middle-Miocene: Badenian) at Müllendorf in the Vienna Basin of Austria. The association comprises: the coral Tarbellastraea reussiana (MILNE EDWARDS & HAIME, 1850,), rhe dare mussel Lithophaga (Leiosolenus) laevigata (QUOY & GAIMARD, 1835), and the barnacle Pyrgoma costatum  SEQUENZA. The corals are preserved only as casts and internal moulds. They are almost completely penetrated by the lebensspuren of L. laevigata and filled with the shells of P. costatum. The development of typical laminar structures in the bore holes as well as their orientation, which is correlated to coral growth, presents conclusive evidence for a biological association..