Before we moved down here from upstate New York, people warned us about huge “palmetto bugs” that scuttled across floors, walked upside-down on ceilings, and generally terrorized homeowners.
We moved to the Lowcountry anyway, and the palmetto bugs were waiting for us.
They were hard to miss, with their large, oval, reddish-brown bodies; sturdy, spiny legs; and long, filamentous antennae.
Technically, palmetto bugs are cockroaches (Periplaneta americana).
The species isn’t native to North America, but was introduced accidentally via ships from Africa in the 1620’s, possibly earlier. It’s one of about 3,500 kinds of cockroaches found worldwide, mainly in tropical and subtropical regions. There are about 55 species in the United States.
Close relatives of termites, roaches are among the oldest of insects, having evolved over 300 million years ago.
Like the smaller German cockroach, plus a few other roaches also associated with human habitations, palmetto bugs spread bacterial and viral diseases (particularly gastrointestinal infections) by contaminating kitchens, food, and serving utensils. Their body secretions produce unpleasant odors, and their excrement, regurgitations, and cast-off “skins” trigger allergies in some people.
The survival skills of domestic cockroaches are legendary.
As most of us know, exterminator visits and frequent house-cleaning deter them, but some escape detection by hiding in hard-to-reach cracks and crevices.
Outside, palmetto bugs flourish under roof shingles and in trees and woodpiles, re-infesting our homes repeatedly.
The nocturnal habits of roaches, combined with a wide-ranging diet (everything from food crumbs to leather, glue, and paper), help account for their resilience.
Palmetto bugs pair up via scents (pheromones) produced by both sexes.
Females package their eggs in hard, little capsules, each containing 14-16 eggs. A single female can produce 1,000 or more eggs during her lifetime of one to two years.
Immature roaches look much like the adults, though they’re smaller and wingless.
Fully grown, palmetto bugs can reach lengths of 2 inches. Although they have functional wings, they rarely fly.
But they can run amazingly fast when alerted to vibrations, thanks to a pair of small appendages at the end of the abdomen. These bear sensitive hairs that conduct nerve impulses to the legs at top speed, bypassing the brain.
One study clocked running American cockroaches at speeds of 50 body lengths per second—the equivalent, for humans, of 210 mph.
Vicky McMillan, a retired biologist formerly at Colgate University,lives on Hilton Head Island. She can be reached at email@example.com.