Field Crickets (House Crickets)
These familiar black, brown, or tan crickets are celebrated singers. There are several species in North America, and many are hard to tell apart. They share in common large heads, hind legs adapted for jumping, and stout, unmovable spines on the hind legs. Adult females have a needlelike (but harmless) ovipositor extending outward from the abdomen; all have a pair of circi extending from the abdomen (each cercus functions like an antenna).
Members of the genus Gryllus are usually shiny black, and the different species are often best separated by singing pattern. The house cricket, Acheta domesticus, is light brown or tannish overall; the tan head has three dark crossbands; the wings of adults extend beyond the tip of the abdomen.