We found 2 of these bugs* in a small container of organic raspberries bought in a store here in Maryland. According to the label on the container the raspberries had been grown in Mexico and were distributed by a company in California.
One of the bugs got washed down the drain and the other I saved. It was in a moribund state from the beginning, able to move its antennae and legs a little bit without actually being able to lift itself up. Nevertheless, it survived in that state for several days before expiring. I figured it was either from Mexico or California. I posted its pictures, along with a tentative genus to the best of my knowledge (which turned out to be wrong), here on BugGuide, but couldn't get an identification. Then I put the insect in a tube, included a label of information about where and when the raspberries had been purchased and gave the lot to a friend whose husband is an entomologist. That was back in early January.
The specimen made its way to the Maryland Department of Agriculture and in an e-mail that came this morning the bug was identified by them as Stenomacra cliens, family Largidae, a native of Mexico. There is a picture of a museum specimen here, where the genus is given as Theraneis.
Let's hope they are not establishing themselves in the U.S.
*Yes, they are true bugs, or hemipterans.