Any of various predatory bugs of the family Reduviidae, which have short, curved, powerful beaks used to prey on other insects or, in certain genera, modified to suck blood from mammals. Also called reduviid. Any of about 4,000 insect species (family Reduviidae) characterized by a thin, necklike structure connecting the narrow head to the body. Many species are common to North and South America. Ranging in size from 0.5 to 1 in. (13-25 mm), assassin bugs use their short, three-segmented beak to suck body fluids from their victims. Most assassin bugs prey on other insects; some, however, suck blood from vertebrates, including humans, and transmit diseases. One species, the large assassin bug, defends itself by accurately "spitting" saliva toxic enough to blind a human