Prehistoric Cockroach Returns Home

The Beetles and The Rolling Stones took America by storm in the mid-1960s, but we all know the basis of their music actually has its roots in American rhythm and blues. While the “British Invasion” seemed like a revolution at the time, the music that the Brit boy toys used to whip American teens into a frenzy actually originated from the good old USA.

Turns out that this isn’t the first time something innately American has returned home. Entomologists have recently discovered that a cockroach genus common in Europe, Ectobius, actually likely originated in North America.

Ectobius has a long history in Europe, including fossil evidence of its existence in Europe dating back 44 million years. Thus, when variants from the Ectobius genus began showing up in small quantities in North America in the 1950s, it was assumed they were “invasive” species that had traveled over in someone’s suitcase or a container shipment.

That was until recently when four ancient Ectobius species were discovered in fossils in the 49-million-year-old Green River Formation near Rifle, Colo. The newly re-discovered species of Ectobius, specifically Ectobius kohlsi, were described in the January 2014 issue of Annals of the Entomological Society of America in an article titled “Native Ectobius (Blattaria: Ectobiidae) From the Early Eocene Green River Formation of Colorado and Its Reintroduction to North America 49 Million Years Later.”

This particular species gets its name from David Kohls, who lives near Rifle, Colo., and sent the fossils to paleontologist Peter Vrsansky, one of the article’s authors.

“About 65 years ago, several entomologists in the northeastern United States noted that four species of Ectobius were present in North America,” said co-author Dr. Conrad Labandeira of the Smithsonian Institution’s National Museum of Natural History. “It was always assumed that these four newcomers were the first Ectobius species to have ever lived in North America. But the discovery in Colorado proves that their relatives were here nearly 50 million years ago.”

Theories of how the cockroaches originally made their way from North America to Europe millions of years ago include crawling their way over via what is now Alaska and Siberia, or crawling up through Canada and over the Atlantic Ocean (remember the continents were once much closer together and that sea levels were much more shallow).

Of course, Keith Richards, who some say looks very fossil-like himself, made it to America via airplane. Luckily, unlike The Stones, it’s unlikely the Ectobius cockroaches will become pervasive pests in America any time soon.

For more information, visit www.ent soc.org.

About the author: Steve Smith is a Cincinnati-based freelance writer.