Nick Upton / Irish moss / Carrageen (Chondrus crispus) attached to rocks, exposed at low tide. Treyarnon Bay, Cornwall, England, UK. September.

Solvin Zankl / Sea lettuce algae (Chondrus crispus) from Roscoff, France. Preserved specimen.

Solvin Zankl / Intertidal rocks covered in seaweeds, including brown algae: Toothed wrack (Fucus serratus), and Thongweed (Himanthalia elongata), red algae: left Chylocladia verticillata, middle Pepper Dulse (Osmu...

Sue Daly / Irish Moss (Chondrus crispus) English Channel, off the coast of Sark, Channel Islands, July

Nick Upton / Irish moss / Carrageen (Chondrus crispus) iridescing in a sunlit rockpool, Rhossili, The Gower peninsula, UK, July.

Nick Upton / Netted dog whelks (Nassarius reticulatus) scavenging on rocks among Sea Lettuce (Ulva lactuca) and Irish moss / Carrageen (Chondrus crispus) seaweeds exposed on a low spring tide, Rhossili, The Gower...

Nick Upton / Colourful mix of Bushy rainbow wrack (Cystoseira tamariscifolia) with turquoise iridescent tips to its fronds and red Harpoon weed (Asparagopsis armata) surrounded by Coralweed (Corallina officinalis)...

Nick Upton / Dense gathering of Common periwinkles (Littorina liitorea) of all ages in a rockpool lined with Coralweed (Corallina officinalis) and Irish moss (Chondrus crispus), North Berwick, East Lothian, July

Nick Upton / Green form of Irish moss / Carrageen (Chondrus crispus) growing in a rockpool, North Berwick, East Lothian, UK, July.

Laurie Campbell / Carragheen / Irish moss seaweed (Chondrus crispus) exposed at low tide, Isle of Skye, Hebrides, Scotland, August

Nick Upton / Split level view of Irish moss / Carrageen (Chondrus crispus) iridescing in a sunlit rockpool alongside Coralweed (Corallina officinalis) and Sea Lettuce / Green laver (Ulva lactuca). Rhossili, The Go...

Nick Upton / Lesser spotted catshark / Dogfish (Scyliorhinus canicula) resting on floor of a rockpool among Coralweed (Corallina officinalis) and Irish moss / Carrageen (Chondrus crispus). Rhossili, The Gower peni...