Chaetosphere larva, spinoid, Marine worm larval, spinning to evade predators,Worm, Marine Polychaete, Fireworm, Amphinomidae, also known as the bristle worms, many species bear chaetae mineralized with carbonate. The best-known amphinomids are the fireworms, which can cause great pain if their toxin-coated chaetae are touched or trodden on. Wikipedia