Cicadas True Bugs and Relatives: Hemiptera

Most hemipterans are active during the day. They spend most of their time feeding on plants, hunting for prey, and searching for mates and sites to lay their eggs. Some species, either as larvae or adults, gather in large, temporary feeding groups. Many species, especially true bugs, defend themselves with special glands that release bad-smelling and bad-tasting chemicals that repel their enemies. The glands open underneath or on the sides of the thorax, or midsection, of adults and on the back of the abdomen of the larvae. The smell released by these glands has given at least one group the common name "stink" bugs.

Aquatic bugs trap layers of air over parts of their bodies or capture a bubble underneath their wings so they can breathe under water. Water scorpions have long breathing tubes on the tip of their abdomen that they use like a snorkel to breath underwater. The exoskeletons, or hard outer coverings, of some aquatic hemipteran larvae are so thin that they can draw oxygen into their bodies directly from the water.

Courtship is usually brief and involves flashing legs, wings, and antennae that are brightly colored or distinctly hairy. Some species produce sounds. Male and sometimes female cicadas vibrate special plates on the sides of their bodies to produce buzzes and clicks that are attractive to potential mates. Some hoppers vibrate their bodies to send signals that travel through stems. Male water striders use their front feet to send ripples over the surface of the water to stake out territories and attract mates. Many species produce pheromones, special chemicals that are used to attract members of the opposite sex as mates.

Males usually deposit sperm directly into the female's reproductive organs. During mating the male may ride on the back of the female, or the pair will become joined at the tips of their abdomens. They may remain together only briefly or for several hours. Terrestrial species usually mate on the surfaces of plants, rocks, logs, or on the ground. Water bugs mate above or below the water surface. Under water they will perch on rocks, logs, or floating plants.

Nearly all species of true bugs must mate in order to reproduce. However, some mealy bugs and scale insects reproduce by parthenogenesis (PAR-thuh-no-JEH-nuh-sihs), a process where the young develop from unfertilized eggs. Nearly all aphids reproduce by switching back and forth between mating and parthenogenesis. In spring and fall, winged males and females mate to produce eggs that hatch into wingless females. These females reproduce by parthenogenesis, giving live birth to more wingless females. At the end of summer the wingless females lay eggs that hatch into winged males and females. Some scale insects are hermaphrodites (her-MAE-fro-daits). Hermaphrodites are individual animals that have both male and female reproductive organs. This means that any two individuals, not just a male and female, can get together to mate to produce offspring.

Eggs may be laid singly or in batches on or near suitable sources of food. Parasitic bat bugs and aphids reproducing by parthenogenesis do not lay eggs and give live birth. The adults of only a few species care for their eggs or young or both. Male giant water bugs remain close to egg clusters in order to guard them. In some species of terrestrial true bugs either the males or females will stand directly over the eggs until they hatch. The larvae of true bugs and many other hemipterans usually resemble the adults but lack fully developed wings and the ability to reproduce. They develop gradually by molting, or shedding their exoskeletons, five times before reaching adulthood. Their life cycles may take just a few weeks or more than seventeen years to complete.