By James A. Bethke.
For all my life I knew an awful lot about bugs and other creepy crawlies, so I was confident when a Master Gardener said she had blue centipedes in her back yard and told her it was unlikely. That was a mistake because she then brought two of them in to the office in a small container a few days later. I thought they were cool! I kept them as pets, fed them well and dragged them to my educational presentations till they perished. I read up on them and found out that they were common in the desert southwest. That’s why when a grower friend of mine sent me the picture of one (Figure 1), I was able to tell him exactly what it was and much more, which he really didn’t care to hear.
This centipede species comes in many different color forms, hence the species name polymorpha, which means many (poly) forms (morpha). The blue centipede, Scolopendra polymorpha Wood, is the only native scolopendrid occurring in California, although there are many other centipede species present. The more common color form that most everyone sees is the light brown form, but they can be yellow, orange, blue, and any gradation in between. If you type in ‘polymorph centipedes’ into your browser and select images, you will see many of the different color morphs. Since blue is my favorite color, the blue centipede is my favorite. These centipedes are a favorite pet for many people, so there is a centipede trade out there where you can purchase your favorite, if you so desire.
Most folks are frightened when they see one of these because they are pretty big for a centipede, and because they can inflict a nasty bite using venom-filled, modified front legs that act like fangs. However, they are also like most arthropods that are full of protein and afraid that you are going to eat them, so as long as you leave them alone, they won’t harm you at all. In fact, they are very good to have around. They are voracious eaters of pest bugs such as crickets and cockroaches, but they will eat most any soft-bodied pest they run into.
One unusual behavior of these centipedes is that they will protect their eggs until they hatch and for a short time thereafter. Many arachnids exhibit this kind of behavior. Occasionally, if you turn over a rock in our area, you may see a centipede coiled around her eggs or recently hatched young.
The world is full of very unusual, yet fascinating creatures and the blue centipedes are one of them. When you see one, I hope you are fascinated rather than repulsed or frightened. They will not charge you or attack you, so just observe them and be happy that you have them near you to get rid of the more pesky pests in your yard.
Fig 1. The blue centipede, Scolopendra polymorpha Wood, 1861.