The venom contains some maculotoxin, a poison more violent than any found on land animals. The nerve conduction is blocked and neuromuscular paralysis is followed by death. The victim might be saved if artificial respiration starts before marked cyanosis and hypotention develops. Cone Shell 400 species of cone shells can inject venom, a few species only are believe to be dangerous. Effects may vary from being painless to excruciating pain.
Salt water seems to make it worse.
Paralysis including respiratory failure may occur. Crown of Thorns Starfish up to 60cm in diameter and with 13 to 16 arms covered with sharp spines. It is usually found in deeper water than other starfish. Possible inflammation, extending to swollen lymph glands areas. Symptoms may continue for weeks or months especially if spines are left in the wound.