Class Chilopoda

Centipedes are reputed to have 100 legs, hence their name. In reality no centipede has 100 legs because they always have an odd number of leg pairs. But some of them have significantly more than 100 legs, Wikipedia reports a minimum number of 30 ranging all the way up to a staggering 354. This reminds me of an old poem

The Centipede was happy quite,

Until a Toad in fun

Said, "Pray which leg goes after which?"

And worked her mind to such a pitch,

She lay distracted in a ditch

Considering how to run (Katherine Craster (1841–74))

Currently, around 3,000 species have been described but it is estimated there could be as many as 8,000. They range in size from a few mm to 30 cm in the giant Amazonian centipede. I have seen a centipede this big near La Junta in Colorado. I was leading a group of Metro State Herpetology students on a field trip and was turning over rocks looking for snakes and lizards. To my amazement I saw a giant centipede running towards me. It was so big that I didn't realize what it was at first but I quickly realized that if anyone was going to believe me I needed to catch it, so ran towards it. A big mistake - I should have let it come to me. It must have detected my feet vibrations because it disappeared under some rocks and I was unable to locate it. I suspect it was Scolopendra heros which is known to reach 20 cm in the wild. I am certain this animal was much longer than that.

It is unusual for centipedes to be active during the day. They lack a waxy cuticle and are thus vulnerable to dehydration. As a result they tend to be nocturnal and remain in moist places during daylight.

As far as we know, all centipedes are active carnivores. Their "fangs" are hollow modified limbs connected to venom glands. The venom varies in toxicity from species to species. The largest species contain venom that can kill bats and other terrestrial vertebrates. Starved centipedes in captivity have eaten vegetable matter so they may be more opportunistic than currently believed.

Centipedes inhabit all of the major land masses (with the obvious exception of Antarctica) and several species have adapted well to human houses where they do a good job of keeping down cockroaches and other pests. Centipedes are an important part of most terrestrial ecosystems and may be a significant predator in some of them. In 2000, a semiaquatic centipede was discovered in Thailand.

It will surprise none of you to know I have been envenomated by a centipede. I was sitting at my dining room table in Suva, Fiji, typing an article when a felt a searing pain like someone had pushed a red hot needle into my ankle. I leapt to my feet to see the perpetrator, a Scolopendra subspinipes (an exotic accidentally introduced species). I am ashamed to say I stomped it to death.

Thereuopoda longicornis - Long-legged centipede

Thereuopoda longicornis, Centipede, Ishigaki, Japan PA272684

Unidentified centipede