photo of bedrock in a rock-pool covered in a brown crust with concentrically zoned growth forms spreading over it. A few periwinkles parked here and there.

Lichen-shaped, but in a rock pool. Looks like Pseudoralfsia verrucosa, a kind of brown seaweed with a crustose growth habit.

#phaeophyceae #pseudoralfsia #rockpool #70s #naturephotography #argyll #scotland #uk