<unk>  are marine invertebrate echinoderms
Found world wide in both shallow and deep waters
Anatomy consists of soft viscera surrounded by a hard plated body ( called a "test") with protruding venomous spines and venomous pedicellariae
Around 950 known species and some are venomous
Nonvenomous species have blunt, rounded spines
Venomous species have sharp, hollow, thin spines
Some have pedicellariae with sharp jaws and venom glands
Nonvenomous species have blunt, rounded spines
Venomous species have sharp, hollow, thin spines
Some have pedicellariae with sharp jaws and venom glands
Nonvenomous spines cause direct trauma
Venoms are known to contain proteases, hemolysins, steroid glycosides, serotonin, cholinergic substances, and rarely neurotoxins
Pedicellariae attach to the victim and break off from the<unk>  releasing venom for several hours
Sea urchins
Toxins
Tapeworm
Ciguatera
Felon
Scombroid
Bougie
Tetrodotoxin 