BOSTON (AP) – A species of beetle never before seen in North America has been discovered in a Massachusetts forest, but the exotic Asian insect does not appear to pose an ecological threat, experts said Monday.

Twenty-two beetles belonging to the “Xyleborus seriatus” species of ambrosia beetle were found in April in traps set by state forestry workers in a wooded area of Southborough. Two or three more were trapped in nearby Stow.

The insects were sent to Cornell University for more research. It’s unclear how they arrived in Massachusetts, but they may have “hitchhiked” here on wooden crates shipped from Asia, Cornell entomologist Richard Hoebeke said.

“My guess is that it has been around awhile and simply gone undetected because nobody was looking for it,” said Hoebeke, who announced the finding in an e-mail to colleagues on July 20.

Each year, an average of a dozen new species of insects are discovered for the first time in the U.S., he said.

“There are a lot of them out there,” said Hoebeke, who has identified several dozen new species since 1978. “More often than not, they turn out to be somewhat innocuous.”

Some species of insects, such as the hemlock wooly adelgid, emerald ash borer and Asian longhorn beetle, can destroy trees and wreak havoc on wildlife habitat. However, most ambrosia beetles feed on fungi in dead or dying trees, not healthy ones.

Scientists know very little about this particular species of ambrosia beetle, but Hoebeke said they only number in the hundreds in Massachusetts and are unlikely to harm the local ecosystem.

On the lookout for invasive species, the Massachusetts Department of Conservation and Recreation has set beetle traps in 15 different parts of the state – part of a “forest health program” it launched in April with a $15,000 federal grant.

The beetle in question is about two millimeters in length and has brown legs and wings. It doesn’t have a common name, so scientists are thinking about naming it the “Southborough beetle.”