Sea urchin shells. Shells of sea urchins (class: Echinoidea). Fused plates form this endo- skeletal test or shell, which encloses the sea urchin body.

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Sea urchin shells. Shells of sea urchins (class: Echinoidea). Fused plates form this endo- skeletal test or shell, which encloses the sea urchin body. As in other echinoderms, including starfish, the body is arranged in five sections. This symmetry is here seen in the five double rows of large pores; from these pores emerge the movable podia (\feet\") usually with suction cups, which enable the sea urchin to move. The external surface of the shell also contains protective spines. Located at the larger hole in the shell (foreground) is the sea urchin mouth, which faces the seabed, while the anus occurs at the smaller opening."

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Size: 3987px × 4945px
Photo credit: © ADAM HART-DAVIS/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: animal, echinodermata, echinoidea, invertebrates, nature, sea, shell, shells, urchin, urchins, wildlife, zoology