DESCRIPTION
Assassin bug adults and nymphs are slender, colorful insects, often blackish, reddish, or brown. They have long legs; a long narrow head, round beady eyes, and an extended, 3-segmented, needle-like beak. Nymphs are quite small, 5 mm (1/4 in) in length when they hatch and grow to an adult size measuring approximately 2 cm (3/4 inch). Insects in this order undergo incomplete metamorphosis. Eggs of Zelus spp. are barrel-shaped, dark brown with a white cap, and are laid openly in groups on plant surfaces. Adults are poor fliers, and both adults and nymphs move rapidly when disturbed. All assassin bugs are predators, some species feed on insects while others feed on the blood of mammals. Insect-feeding species eat a wide variety of small to medium-sized insect prey including caterpillars, leafhoppers, other bugs, and aphids. They also feed on beneficial species such as lacewings. Nymphs and adults are often seen stalking or laying in wait for their prey, which they inject with venom once they have caught. Assassin bugs are common natural enemies on many plants, including row and tree crops.