Lichina confinis

Lichina confinis

Observation - Lichina confinis - UK and Ireland. Description: Very dark olive-brown lichen with a 'cracked' surface growing just above high tide level. I think this is Lichina confinis, but wonder if the black, smoother lichen below it in picture 2 and over which it appears to be growing is either where it may have

Very dark olive-brown lichen with a 'cracked' surface growing just above high tide level. I think this is Lichina confinis, but wonder if the black, smoother lichen below it in picture 2 and over which it appears to be growing is either where it may have been browsed or perhaps is another species altogether - perhaps a Hydropunctaria?