Tube Sponge
Fig. 1: One of the tube sponges that filter out plankton from the Caribbean waters around Curaçao. TG 672, Playa Lagun dive site, Curaçao. Nikon D200; Δt=1/250 s; f=10.5 mm; f/4.0; ISO 100; 10 November 2019 11:15:23