This sea urchin, with its dazzling array of sharp spines, was seen while exploring Horizon Guyot, a manganese-encrusted seamount located north of Johnston Atoll, during the 2017 Laulima O Ka Moana: Exploring Deep Monument Waters Around Johnston Atoll expedition. These sea urchins use their spines to dig through sediment, which they ingest and remove any organics (food) in the sediment before excreting the leftover sediment as waste.