Calliostoma zizyphinum. Site: NW Portstewart Point
 Calliostoma zizyphinum. Event number: 19840705/01. Site: NW Portstewart Point. 1984-07-05. Photograph © David Connor. (12/13) 
 David Connor (2026). Photograph of Calliostoma zizyphinum. Site: NW Portstewart Point. [In] Marine Biodiversity Data Portal - NI.
https://habitas.org/mbdp/sitephoto.php?item=niss_7453.jpg. Accessed on 2026-11-04