Call it the invasion of the camels -- camel crickets, that is, an invasive, cannibalistic Asian species taking up residence in homes in the eastern U.S. that researchers say we still know little about.
Although the species Diestrammena asynamora, or greenhouse camel cricket, has been seen in the United States for decades, it was thought to be mostly confined to commercial greenhouses.
Not any more, researchers at North Carolina State University are reporting; it has moved out of those environs and has become so widespread in the East that it's more commonly seen than the region's native camel cricket species.
Also known as spider crickets and cave crickets, camel crickets are so named because of their arched "humped" back and long hind legs.
The NC State researchers initiated a "citizen scientist" study, asking the public to contribute photos or specimens of crickets living around their homes, or to respond to a survey on a website.
Most of the responses came from east of the Mississippi River, the researchers found, and the invasive camel cricket variety seemed to be much more numerous than native species.
In North Carolina, they reported, the Asian D. asynamora accounted for 92 percent of submitted camel cricket samples.
"We don't know what kind of impact this species has on local ecosystems though it's possible that the greenhouse camel cricket could be driving out native camel cricket species in homes," study leader Mary Jane Epps says.
The numbers of D. asynamora compared to native species wasn't the only surprise the study yielded, the researchers say.
"There appears to be a second Asian species, Diestrammena japanica, that hasn't been formally reported in the U.S. before, but seems to be showing up in homes in the Northeast," Epps says. "However, that species has only been identified based on photos. We'd love to get a physical specimen to determine whether it is D. japanica."
Finding camel crickets in a home is not a cause for panic, the researchers say; they don't bite or present any threat to people.
"Because they are scavengers, camel crickets may actually provide an important service in our basements or garages, eating the dead stuff that accumulates there," says study co-author Holly Menninger.
Despite the numbers of the Asian crickets in the U.S. and their long presence here, remarkably little is known of the species' biology or their interactions with other insect species, she says.
"We're interested in continuing to study them, and there's a lot to learn."
