Centipedes and Millipedes, Pacific Northwest
Centipedes & Millipedes can be found all over the Pacific Northwest. Centipedes can easily be distinguished from millipedes by counting the number of pairs of legs arising from most body segments, millipedes have two pairs, while centipedes bear one pair per segment, with the first pair of legs being modified into fangs.
Centipedes are generally flattened and have a pair of well developed antennae on the head. Some centipedes, such as the house centipede have long legs and are capable of running rapidly.
The largest centipedes may grow to be about 15 cm long. Millipede bodies are rounded or somewhat flattened. Legs are short and movement is slow, with movement of legs appearing wave like. Most species are less than 4 cm long.
Centipedes & Millipedes spend the winter as adults in protected habitats and become active in the spring. During the warmer months, females lay eggs in soil and cover them with a sticky substance, although some species give birth to living young.
Immature stages (larvae) hatching from eggs several days later are similar to adults but smaller, having fewer leg bearing body segments.Additional leg bearing segments are produced with each molt. Millipedes develop through about seven stages in 21 to 25 weeks. Some centipedes are known to live to 6 years.
Centipedes & Millipedes prefer to live in moist habitats and during the day hide underneath rocks, logs and other objects in contact with the ground. They are active at night. Centipedes feed on insects and spiders.
They kill by grasping prey with their powerful fangs and injecting venom. The fangs are located on the body segment just below the head. Millipedes feed on decomposing organic matter, but will occasionally damage seedling plants by feeding on leaves, stems and roots.