Hav., (1936); and Placodium lobulatum The vegetative body of the lichen, the thallus, is orange or orange-red in colour and may be continuous or fragmented.

When fragmented the thallus looks lumpy under a hand lens; when continuous it is areolate and the margins may be ill-defined with almost no lobes; it is never powdery or pruinose.

[1] Caloplaca marina is found on coastal rocks from calcareous to high silica rich types (HS).

It is characteristically found in the mesic supralittoral zone or above Verrucaria maura (tar lichens).

[6] Caloplaca marina is at first unaffected by oil spills and cleaning, but dies off within twelve months.