Polymastia boletiformis, Calliostoma zizyphinum, Flustra foliacea, Leptasterias muelleri. Site: S of Black Rock, Skerries, Portrush 
 Polymastia boletiformis, Calliostoma zizyphinum, Flustra foliacea, Leptasterias muelleri. Event number: 19790618/01. Site: S of Black Rock, Skerries, Portrush. 1979-06-18. Photograph © Ulster Museum. (1/1) 
 Ulster Museum (2026). Photograph of Polymastia boletiformis, Calliostoma zizyphinum, Flustra foliacea, Leptasterias muelleri. Site: S of Black Rock, Skerries, Portrush. [In] Marine Biodiversity Data Portal - NI.
https://habitas.org/mbdp/sitephoto.php?item=niss_1059.jpg. Accessed on 2026-11-04