Alex Mustard / Bootlace weed / Mermaid's hair (Chorda filum) Porthkerris, Lizard Peninsular, Cornwall, UK August

Alex Mustard / John Dory (Zeus faber) swims through a forest of Bootlace weed / Mermaid's hair (Chorda filum) Porthkerris, Lizard Peninsular, Cornwall, UK August

Solvin Zankl / Dead man's rope algae (Chorda filum), Purbeck Marine Wildlife Reserve, Kimmeridge Bay, Dorset, UK, July.

Bernard Castelein / Bootlace Weed (Chorda filum) on beach, Causeway coast, Antrim county, Northern Ireland, UK, September.

Bernard Castelein / Bootlace Weed (Chorda filum) on beach, Causeway coast, Antrim county, Northern Ireland, UK, September.

Bernard Castelein / Bootlace Weed (Chorda filum) on beach, Causeway coast, Antrim county, Northern Ireland, UK, September.

Chris Gomersall / 2020VISION / Bootlace seaweed (Chorda filum) in the sea around the Cairns of Coll, Inner Hebrides, Scotland, UK, July 2011

Ingo Arndt / Lyngbye (Chorda tomentosa) algae four centimeters, Helgoland, Germany

Graham Eaton / Bootlace weed (Chorda filum) on seabed in clear, shallow sea, Rhosneigr, Anglesey, Wales, Irish Sea, UK. July.

Alex Mustard / Dense growth of Bootlace seaweed (Chorda filum) in shallow water, Kimmeridge, Dorset, England, UK, English Channel. July. Wildlife Photographer of the Year Competition (WPY) 2022 - Plants and Fungi ca...

Alex Mustard / Dense growth of Bootlace seaweed (Chorda filum) in shallow water in summer, with a single plant of invasive Wireweed (Sargassum muticum). Kimmeridge, Dorset, England, UK. English Channel. July.

Alex Mustard / Dense growth of Bootlace seaweed (Chorda filum) in shallow water, Kimmeridge, Dorset, England, UK, English Channel. July.