Centipedes

Centipedes

Centipedes, despite their resemblance to millipedes, are not very closely related, and are placed in a separate class within the arthropods known as Chilopoda, from the Greek words for "jaw feet". This is a reference to the venomous fangs, which are actually formed from modified legs. The centipedes are some of the oldest terrestrial animals on earth, and some of the very first creatures to crawl from the sea onto the land were probably very similar in appearence to modern centipedes.

All of the centipedes are nocturnal predators which live by actively hunting down insects and other small prey animals. They are found mostly in tropical forest areas, but have also established themselves in temperate forests and desert areas. Although popularly referred to as "hundred-leggers", most centipedes have between 15 and 30 pairs of legs, one pair on each body segment.

There are four orders of centipedes within the class Chilopoda. One of these is the Lithiobiomorpha, known as stone centipedes. Small and secretive, they live under rocks and in leaf litter and are not often seen. The snail centipedes, of the order Geophilomorpha, are small yellow animals that live in rotting logs and soil. The centipedes most often seen by people in the United States are the house centipedes, of the order Scutigeromorpha. They are of small size and have long thin legs. Most of these are found in southern Europe and the Middle East -- in the United States, they cannot survive outdoors and instead live in people's houses. The largest of the chilopods are the tropical centipedes in the order Scolopendromorpha. Found in warm and damp areas of the world, the tropical centipedes are several inches long, with the largest species approaching one foot in length.

Almost all of the "pedes" available in the pet trade are from the order Scolopendromorpha. These are large arthropods, averaging five or six inches in length and either 21 or 23 pairs of legs. The largest members of the group can reach lengths of twelve inches. The scolopendromorphs are fast-moving and aggressive, and can inflict painful wounds. All are predators which attack their prey with venomous fangs, and in some species the venom is powerful enough to kill small vertebrates. Although there are has only been one reported case of a human death resulting from a centipede, they can deliver painful bites and should not be handled.

Some of the larger scolopendromorph centipedes have lifespans of over ten years.