Centipedes - Venomous Creature

CENTIPEDES

Centipedes belong to Chilopoda. There are four orders: Scutigeromorpha, Lithobiomorpha, Geophilomorpha and Scolopendromorpha (the most venomous centipedes). Centipedes possess long, dorsoventrally flattened bodies with 15 to 181 somites (each of which has a pair of legs), a head bearing a pair of multijointed antennae, and three pairs of mouth parts (Fig12.52). The number of segments is always odd, so there is reallyno 50-segment centipede with 100 legs.** Every segment, with the exception of the last one, has one pair of legs. Centipedes can grow up to 20 cm. The venom fangs are in the first segment. Three pairs of modified appendages which compose the mouth parts include the most important appendage, known as the venom claw, or “jaw”. A neurotoxic venom is injected through venom ducts. Bites from the centipede are typically pointed in shape.

Centipedes are common in forests, but are also encountered near human habitations, infesting drains, kitchens, and bath-rooms. They can inflict painful bites characterised by immediate local burning pain, erythema, swelling, inflammation, superfi-cial necrosis, lymphadenopathy, and lymphangitis. 

The oedema may last for several hours. Local pain may be excruciating and the wound may bleed profusely. The commonest genus encoun- tered in India is Scolopendra. Occasionally, systemic features are seen: anxiety, dizziness, vomiting, headache, convulsions, irregular pulse, and cardiac arrhythmias. Rhabdomyolysis, and renal failure have been reported with the Giant Desert Centipede (Scolopendra species).

Treatment is supportive. Bitesite is treated in the same manner as for a scorpion sting. Pain can be treated with application of ice over the injured area. Severe pain may require injection of local anaesthetic. A topical corti-costeroid, antihistamine, local anaesthetic combination may be of value in controlling inflammation and itching. Tetanus prophylaxis should be considered.