Cottonwood borers (mating pair)

The adult cottonwood borer is a large, longhorn beetle with a black-and-white coloration and black antennae as long or longer than the body. The white portions are due to microscopic masses of hair. The larvae are legless, cylindrical, creamy-white bodies with a brown-to-black head and grow up to 38 millimeters (1.5 in) long. (information from Wikipedia)