The SETAE (hair-like structure that covers their body) are ATTACHED TO UNICELLULAR POISON GLANDS at the base of each hair. The urticating hairs, or setae, are effective defensive weapons that protect some species from predators. setae or hair has poison ● Localized pain as well as PAPULES (SOMETIMES HEMORRHAGIC) & HEMATOMAS; ● Headache, nausea, vomiting, HEMATURIA ● LYMPHADENITIS & LYMPHADENOPATHY ● SEVERE CASES: CEREBRAL EDEMA, HEMORRHAGE (INTRACRANIAL HYPERTENSION), and MENTAL CHANGES have been noted for foreign species.