Field Guide to Venomous and Medically Important Invertebrates ...

Millipedes
Millipedes (Class Diplopoda) superficially resemble centipedes, but they have two pairs per
body segment, and the body is circular in cross-section. They range in size from near
microscopic to several inches in length for some tropical species. Millipedes can be found in a
variety of terrestrial but usually damp, habitats, including under various ground shelters, leaf
litter, soil, and rotting wood. Unlike centipedes, millipedes are sluggish in their movements.
Most millipedes are completely harmless, secretive, and do not bite. However, some species,
when alarmed will roll into a coil and excrete noxious chemicals from pores along the sides of
the body. These chemicals vary in potency among species, but they usually have a highly
offensive odor. Some tropical millipedes produce excretions that may cause burning of the eyes
and skin, and they are capable of ejecting these chemicals for up to a yard (meter). Reactions
may include yellow or brown staining of the skin, intense burning and itching of the skin,
occasionally blistering, and, in severe cases, marked reddening of the skin, and necrosis. When
the eyes are invloved, these secretions may cause severe conjunctival reactions with corneal
ulceration. Symptoms usually resolve within 24 hours, but if the eyes are involved, recovery
may take several days. Species known to be injurious include Rhinocricus lethifer (Haiti),
Rhinocricus latespagor (Haiti), Polyceroconas spp. (Papua New Guinea), Spirostreptus spp.
(Indonesia), Iulus spp. (Indonesia), Spirobolus spp. (Tanzania), Orthoporus spp. (Mexico), and
Tylobolus spp. (California).
Figure 223. Millipede in a defensive coil. Photo: source unknown.
Figure 224. A tropical millipede. Photo: Easy Exotics.