The harlequin cockroach gets its name from the variegated appearance of the adults. The scientific name is Neostylopyga rhombifolia (Stoll).
Many experts believe the harlequin cockroach originated in Southeast Asia. Because of commerce, it has been transported to many other places. It is now established in Australia. It has also been transported to Mexico. From there it has spread into Southern California and Arizona.
Even though the harlequin cockroach has spread to various parts of the world, it is not considered to be a pest. There are very few reports of harlequin cockroaches invading homes in the United States.
The harlequin cockroach grows to be almost 10.5″ long. The female produces an egg case, called an ootheca. The female carries the egg case for a few days before leaving it in a suitable area to hatch.
In the immature, nymph stage, the roaches are tan-colored insects. As they grow the nymphs molt or shed their skin. Each time they molt, they develop more of the pattern of the adult roaches.
Both male and female harlequin cockroaches have very short front wings. Their back wings are absent altogether. Because of this, they do not fly. However, they can run very fast.
Because of its colorful appearance, the harlequin cockroach is popular with people who keep cockroaches as pets. People who are thinking about raising these cockroaches are cautioned that, like many other roach species, the harlequin cockroaches are excellent climbers.
Smooth vertical surfaces are not obstacles. They can easily climb out of glass containers where people keep them. Experienced cockroach keepers suggest applying a coating of petroleum jelly around the rim of the container to keep the roaches from climbing out and escaping.