Hemiptera (True Bugs, Cicadas, Leafhoppers, Aphids, Mealy Bugs, and Scale Insects)

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Hemiptera

(True bugs, cicadas, leafhoppers, aphids, mealy bugs, and scale insects)

Class Insecta

Order Hemiptera

Number of families More than 140


Evolution and systematics

Most of the diversification of the Hemiptera started in the late Paleozoic (Upper Permian), and the major lineages diverged early in the Mesozoic (Triassic). Regrettably, some key fossils come from beds of uncertain age. Well-preserved, complete fossils are scarce—for example Karabasia evansi (family Karabasiidae, Upper Jurassic?); Architettix compacta (family Cicadoprosbolidae, Cretacic); Incertametra santanensis (family Hydrometridae, Cretacic). For the most part only isolated structures have been reported, and many of them have not been assigned with certainty to groupings below the family. Certain very-well-preserved specimens are known from amber, such as Metrocephala anderseni (family Hydrometridae) and Succineogerris larssoni (family Gerridae) from Baltic amber (Eocene), and Brachymetroides atra (family Gerridae) and Halovelia electrodominica (family Veliidae) from Dominican amber (Oligocene-Miocene). Several schemes of phylogenetic relationships among Hemiptera have been proposed, based on varying criteria. In the last decades of the twentieth century, they succeeded at short intervals, with remarkable discrepancies among them, and the proposed schemes are in steady flux.

The partitioning into two suborders, Homoptera and Heteroptera, or into three, segregating the Coleorrhyncha, does not express the inferred (and most accepted) paths of evolution. The relationships between Heteroptera and Homoptera and between suborders and infraorders of both major groupings have been discussed in many papers by several hemipterists; interesting results were obtained by the end of the 1980s, based on important paleontological, chemical, morphological, cytogenetical, and behavioral facts of living Hemiptera. The Heteroptera plus the Coleorrhyncha represent the most advanced grouping, derived from an extinct homopterous stock of Scytinopteroidea. Updated and adjusted results were edited by Schaefer.

The Hemiptera are divided into four undergroupings: the aphids and scale insects (and perhaps the whiteflies), included in Sternorrhyncha; the cicadas, leafhoppers, treehoppers, plant-hoppers (and perhaps the whiteflies), included in Auchenorrhyncha; the conenoses, water bugs, stink bugs, and others, included in Heteroptera, or true bugs; and the moss bugs, included in Coleorrhyncha. The Sternorrhyncha and the Auchenorrhyncha together are called Homoptera; the systematic position of the whiteflies is still dubious. The Coleorrhyncha and Heteroptera make up the suborder Prosorrhyncha. The Sternorrhyncha are clearly monophyletic (derived from a single ancestor). The Auchenorrhyncha do not appear to be monophyletic; they comprise two infraorders, the more primitive Fulgoromorpha and the more advanced Cicadomorpha. The monophyletic Heteroptera, or true bugs, are grouped into eight infraorders: Enicocephalomorpha, Dipsocoromorpha, Gerromorpha, Nepomorpha, Leptopodomorpha, Cimicomorpha, Pentatomomorpha, and Aradomorpha. The Coleorrhyncha, with a single family, restricted to the Southern Hemisphere, evolved parallel to both Homoptera and Heteroptera. The exact number of families of Hemiptera is largely a matter of opinion; by 2003 approximately 140

extant families were accepted, some 60 in Homoptera, about 80 in Heteroptera, and one in Coleorrhyncha.

Physical characteristics

The body shapes are extremely diverse, ranging from plump, short, and cylindrical—such as the terrestrial scutellerid bugs and the aquatic pygmy backswimmers—to very slender—such as the semiaquatic water measurers, and some members of the assassin bug family—or even extremely flat—such as the aradid bugs. The sizes range from 0.03 in (0.8 mm: litter-dwelling bugs and some plant lice) to about 4.3 in (110 mm: giant water bug); of course, larvae in every case are much smaller. The head bears a beak, bent backward against the venter and varying from almost inconspicuous, as in the family Corixidae, to very long, reaching the rear end. It is a gutter-shaped, articulated labium holding the distal part of the very long and slender stylets. The antennae may be very short and concealed under the head border in aquatic bugs or longer and exposed in almost all other Hemiptera species. Although most adult hemipterans bear two pairs of wings, some are always wingless, like the females of scale insects. In Heteroptera the forewings are called hemelytra (derived from the classical Greek hemi, half, and elytron, case or etui), because the basal half is mostly stiff and the distal one is membranous. In some Auchenorrhyncha they are called tegmina (classical Greek for carapace, a somewhat flexible but fairly stiff structure), since they are entirely stiff. Hind wings are membranous and translucent or whitish; some Homoptera have all four wings of the same texture (aphids and cicadas, among others). The legs have a wide adaptative spectrum: for walking, running, jumping, swimming, or skating on water; for grasping prey; or for digging. Only seldom are legs missing. Larvae generally are similar to small adults but lack wings and genital appendages; the larvae of some Homoptera, however, are quite different from adults. In the whiteflies, adults are slender, with long legs and ample membranous wings, and the larvae are broad and flat, scale-like, and lack legs.

Many hemipterans are dull-colored, for instance, most aquatic species; others display bright and contrasting colors, sometimes with a showy metallic shine. The color may be uniform, but stripes, dots, or extensive contrasting and brightly stained areas frequently appear. Larvae can be similar to adults in color or differ greatly; some evenly stained species may have spotted larvae, among them, many stinkbugs. Underground-dwelling cicada larvae are colorless or pale yellowish. The body surface sometimes is obscured by a whitish, compact, powdery, woolly, or filamentous wax cover, as in the mealy bugs and whiteflies.

Numerous hemipterans, such as the members of the stinkbug family, have scent glands, which are used against predators, as an alarm signal, or as a call to aggregation. These glands open ventrally or laterally in the hind thorax in adults, and dorsally on the abdomen in larvae. The strong smell justifies the name "stink bugs" for these offensive stinking species. Many families display alary polymorphism—individuals may have complete wings, reduced wings, or no wings. Fliers and nonfliers may coexist in a population, and proportions seem to be linked to the habitat. Among bugs living in the water, reduction affects only the hind wings; the forewings are complete, holding air for buoyancy. Several bugs living under water have adaptations for taking in oxygen at the water surface, such as siphons or dry, hairy areas. Some larvae take oxygen from the water itself.

Distribution

The Hemiptera are distributed broadly, both on land and in freshwater; moreover, the only insects dwelling on the open ocean are all bugs. On all continents families are more diverse in the tropics. In high boreal latitudes and high altitudes the ranges of some families extend close to permanent ice. Even remote oceanic islands such as Tristan da Cunha in the Atlantic and the Easter Islands in the Pacific are populated.

Habitat

Hemiptera may be either terrestrial or aquatic. They occur in almost all habitats, including deserts and at high altitudes. Those that have aquatic tendencies occur in every freshwater, brackish water, and saline habitat, including the open sea. Most hemipterans are terrestrial and dwell on plants (including roots), on the ground, in soil litter, or as external parasites on vertebrates. Many are linked to running or standing freshwater, living on the surface (semiaquatic bugs) or in the water (aquatic). Some live in water-filled tree holes or in epiphytic plants. Few are marine—only five species live on the surface of the open ocean. Certain species dwell in natural caves or those excavated by crabs. Others live in nests of social insects (ants and termites), or of birds. Still others live in spider webs.

Behavior

Most species are diurnal and dwell on the ground or on plants, searching for food or prey, for a mate, or for a suitable egg-laying site; every part of a plant, including the roots, may serve these purposes. Aquatic bugs thrive in or on water, frequently among aquatic plants, and almost all are predaceous. Stones, twigs, and other substrates may serve as perches or shelters, especially in swift-running brooks, or as egglaying sites. In the water they swim or crawl on the bottom or on supports (aquatic bugs); on the surface they walk or skate (semiaquatic bugs). Females and advanced larvae of most scale insects do not move from the site upon which they set

down (only the first larval instar has active legs and moves around); the tiny males are winged and fly in search of ripe females. No hemipteran is truly social, as are ants and termites and some bees and wasps, but some live in dense aggregations, sometimes only transitorily.

Visual displays are achieved by expanded legs, wings, or antennae, which sometimes also are brightly or contrastingly stained or very hairy. Sounds are produced by scraping together two sclerotized parts of the body or by vibrating the tymbals, as in the cicadas; specialized hairs receive the sound waves. Some bugs drum with their legs on the substrate, and others (e.g., certain assassin bugs) scrape their beaks against their own chests, the vibration being transmitted via the legs to the substrate. Males of many water striders produce ripples on the surface with their legs, which are detected at a distance. Scent substances, the sex pheromones, usually are present too. All these signals are highly specific for attracting sexes to each other; some individuals can identify them and decide to flee, avoiding competition with individuals that had previously arrived and may have already established their territories.

Many hemipterans disperse by flight, especially water-dwelling species. Dispersal capacity may be retained for life or soon lost. Rain-pool species can fly almost their whole life span, and they successively colonize habitats avoided by stability-loving species, thus lessening the risk of competition because they are able to support environmental instability. No hemipterans have spectacular migratory swarms, and they do not fly great distances, as do certain butterflies, but some observations suggest that giant water bugs can fly many hundreds of kilometers at a time. In the dry and warm season, plant lice start shorter migrations by the thousands, producing a sort of fog. Territoriality was studied in only a very few Hemiptera species, and the results are not understood clearly. Signals, both mechanical and chemical, play an important role in marking territorial boundaries, as seems to be the case among certain water striders and large coreids.

Feeding ecology and diet

All the Homoptera are sap feeders. Heteroptera are primarily predaceous, and in the course of evolution several groups have evolved to exploit plants; some of these groups evolved and returned to the predatory condition or shifted to parasitism on higher animals. All take only liquids in the form of plant juices, chiefly sap, or animal juices, chiefly predigested tissues or blood; only a few water bugs are able to add small particles to their diet, such as algae. Plant juices are taken from leaves, stems, buds, flowers, fruits, or roots. Some species suck the contents of fungal threads under rotting bark; others suck from moss cells. Predators suck from almost every arthropod; some prefer snails; and others may attack small fish, frogs, and tadpoles. Certain bugs feed on dead or half-dead arthropods, mainly insects. Those that suck blood take only warm blood from birds or mammals, mostly bats. Cannibalism may occur, primarily in gregarious species. Some Hemiptera do not feed as adults, for example, the males of scale insects. Food is obtained in the places they live, but blood-sucking bugs rest in shelters and leave their shelters to bite warm-blooded hosts.

Water striders' main food consists of aerial insects blown onto the water surface; they localize these prey by the ripples they produce with their helpless movements. Oceanic bugs feed on dead, floating jellyfish, and on planktonic microcrustaceans and fish larvae trapped in the surface film. Larvae of most Hemiptera thrive and feed in the same manner as adults, but some stink bugs take sap at the first larval instar and later become predaceous like the adults. Adult cicadas take sap from twigs, but larvae dwell underground and take it from roots. The first-instar larvae of some species eat no food. Some Sternorrhyncha produce anomalous growths in leaves, stems, or roots, called "galls"; larvae and newly molted adults feed and develop therein, without seriously interfering with the plant's physiology. Some Homoptera that take dilute resources, such as plant sap, eliminate much of the water immediately, concentrating the nutritive substances. They excrete some sugar with the liquid feces, which, if abundant, can be used as food by mammals and humans, as the biblical "manna." Often a black mold that resembles soot develops on that substance and affects plant growth as it restricts the amount of light that reaches leaves.

The saliva may form a small cone on the plant surface, helping hold the slender mouthparts in position. Other saliva components break the cell walls down, to release the contents. Some bugs feed on dry seeds, piercing them to inject a digestive saliva and sucking the resulting fluid. Still others inject a plant hormone mimic, which mobilizes nitrogen-rich substances to the wound.

Reproductive biology

Courtship and mating take place mostly on perches among terrestrial species, generally on plants but sometimes on the ground or in shelters. Courtship, if any, is frequently brief and consists of chirps, scent emissions, or displays with the legs or antennae or a combination of these types of behavior. Courtship activities are undertaken by the males, but in some species females collaborate; in most boatmen the loud male chirps are answered weakly by females, allowing for mutual localization. Some bugs living in the water alternately take and expel air, thus rising and sinking at the surface and forming coarse waves, which orient the partner. Water bugs mate above or below the surface; submerged and floating plants and logs may serve as perches.

At mating the male mounts the female, but sometimes he shifts to an end-to-end position. The male also may lie at an angle across the female or beside her. Coupling may be brief or may last for hours. Insemination is internal, the male transferring sperm with specialized intromittent organs (a rather complex aedeagus). So-called traumatic insemination is known in a couple of families: males slash the abdominal wall of females with their swordlike claspers, discharging sperm in the general cavity. The number of scars shows how often a female has mated. Immobile, wingless female scale insects are mated by the winged males, which may have a very long copulating organ to reach beneath the shield or the wax cover.

Parthenogenesis (reproduction without mediation of males) is extremely rare in Heteroptera; it is mentioned in only a couple of unrelated species. It is frequent, however, in certain Sternorrhyncha. Most plant lice, for example, alternate yearly between one bisexual reproductive phase and few to many parthenogenetic phases, the females giving off living larvae, which in turn give off living larvae. At the end of the season, a bisexual, frequently winged phase reappears. Some pest plant lice are permanently parthenogenetic in warm areas. Some scale insects may be bisexual or parthenogenetic, depending on environmental or geographic factors.

Eggs are often barrel-shaped, more or less elongated, and sometimes weakly curved; they may bear a long stalk. The shell is translucent or whitish, but frequently the stained vitellum makes them brightly colored. The surface is smooth or rugose or is ornamented with spines, tubercles, crests, and so on, giving them a bizarre appearance. Eggs laid under the water's surface have a thick and complex shell, formed by extremely fine spun work, which traps the tiniest air bubbles, providing oxygen for the embryo. Most eggshells have a weak strip, which breaks at hatching; it may form a distal ring, defining a cap, which drops away. In some species the strips form a distal rosette: the shell "bursts," and the larva emerges through the opening. Some banana-shaped eggs are embedded in aquatic plants, and the strip is longitudinal, allowing for easy emersion (emergence from the egg). Many first-instar larvae bear a sharp "egg burster" on the head, which tears the eggshell.

Eggs may be laid singly or in groups in suitable sites for the emerging young to find food soon. Most plant-feeding bugs glue eggs with a special secretion; aquatic and aerial bugs embed them into tissues. Predators and blood-feeders glue them to a firm substrate or let them drop to the floor of the host's resting site. Many scale insects hide the egg batch below themselves or below the rigid dorsal shield or below a wax cover. Among certain giant water bugs the female lays the eggs on the back of the male. Bat parasites do not lay eggs; instead, they retain and nourish the young in the genital tract.

No hemipteran species spins nests or egg cases. Only a few species care for eggs or young or both. Males of some giant waterbugs protect the eggs glued to their backs and clean them using their legs, which also ensures an oxygen supply for the embryos. Males of other giant water bugs stay near the egg clusters laid on twigs emerging out of the water, guard them, and readily threaten potential egg predators. Egg guarding has been observed in isolated cases among several terrestrial families; the female or male covers the egg batches until they hatch. This behavior perhaps is more frequent than usually is assumed. The best protective action probably is to select a proper site for laying the eggs, lowering the risks at hatching.

Many hemipterans living in temperate zones have a single yearly reproductive cycle, but some have two or more generations per year. Exceptions are the cicadas, which have an extended larval development lasting several years. Embryos or adults, but rarely larvae, overwinter; some species aggregate en masse to pass this period. In the tropics generations frequently overlap, and insects at all stages of development are found there year-round. If marked climatic seasonality occurs (humid vs. dry and warm vs. cold), estivation or hibernation may take place. The unfavorable season sometimes is passed

in a dormant, hormonally driven diapause; the embryo, the larva of every instar, or the adult may engage in this diapause, which may last up to half a year or even more (nine months in one Alaskan shore bug).

Conservation status

Among insects, hemipterans are not a frequently mentioned group of conservation concern. By 2002 the IUCN Red List had cited only five species of Homoptera (two Extinct and three Near Threatened) and no species of Heteroptera. There are some regional listings for Europe, North America, New Zealand, and other countries, which also include very few Hemiptera. More extensive samplings might indicate that more species are of conservation concern.

Among wild species, decline follows environmental damage. For aquatic species, water pollution is a widely occurring alteration. For water striders and the like, any surfactant present in the water, even in low amounts, is lethal. Extensive control of pests with insecticides, which are never specific, put at risk every insect, whether a pest or not. Extensive forest clearing eliminates many scarce trees and shrubs, perhaps the only food resource of some bugs, and also water-filled epiphytic plants where some bugs live. Forest clearing also increases the light intensity at the ground level, affecting shade-adapted plants and insects. Only in protecting ecosystems and ensuring their sustainable use will the Hemiptera be protected.

Significance to humans

Humankind profits from bugs by eating them, by using them against pests, and as models in art. Bugs are also used as a source of amusement and entertainment; for example, cicadas are often tied together with thread to make decorations or jewelry, and children have races with insects. On the other hand, humankind suffers from bug bites, from illnesses transmitted by certain species, and from agricultural pests. Some Mexicans eat the egg masses of the boatmen species, called "ahuautle." Shrub twigs are drowned in ponds after large amounts of eggs have been glued to them; eggs are later gathered and either fried or dried in the sun. In India the adults of one species of giant waterbug are cooked in syrup, which is considered an expensive delicacy. Roasted, egg-filled female cicadas are eaten in some Asian countries. In several places, stink bugs are dried and powdered for use as a condiment. People have engaged in other forms of recreational and ceremonial insect eating.

Cicadas have received considerable attention, as it is said that their chirps predict warm or stormy weather. They have been highly regarded as symbols of resurrection. In the Far East jade carvings in the shape of cicadas once were put in the mouth of dead princes and other important people. The Chinese keep cicadas in cages, like singing birds, and also fly kites made in their shape. Kissing bugs, especially the domestic species that transmit Chagas' disease, are reputed to bring luck and happiness, which has made them popular and has contributed to the dissemination of the illness and constraining sanitary controls. A few predaceous bugs are used as biological control agents against crop pests and are reared to be released in the field. Some species of stink bugs, chiefly a plant feeder family, are efficient at attacking pest caterpillars on soybean plants; certain species ingest and transmit caterpillar disease viruses (e.g., polyhedrosis virus).

Carmine is a very valuable dyestuff produced by an American cactus-dwelling scale insect; the plant and the insect were introduced to other continents by the eighteenth century, producing a noxious spread of the weed that rendered vast tracts of land unusable. Shellac is produced by another tropical scale insect that dwells on fig trees. Several Hemiptera occurring on different wild plants shifted to crop plants once they were introduced into new areas and then turned into pests. Some are genus specific or family specific; others are generalists. The ensemble is extensive and includes many of the plant-feeding bug families. The pest condition is achieved through the generous food supply offered by cultivation, encouraging insect numbers to rise quickly. Families with many serious pest species are Aphididae, Coccidae, Diaspididae, Delphacidae, Pentatomidae, Miridae, and Alydidae, among others. Underground-dwelling larvae of some cicadas may cause locally severe losses in sugarcane fields. Often the damage caused to crops is not so much due to the removed sap but to the transmission of microbial diseases, mainly plant viruses and fungi. Species of the family Delphacidae cause losses in corn and other cereals by transmission of viruses; some Pentatomidae transmit disease-producing fungi. One American species of Phylloxera may produce severe damage in the production of grapes by attacking the roots and leaves of the vines; they have caused extensive losses in European countries where the species was accidentally introduced.

Some water bugs, and members of the assassin bug family sting very quickly with their mouthparts when they are taken by hand, injecting a poisonous saliva and causing intense pain and sometimes swelling. Some exclusively blood-sucking bugs attack humans and may transfer parasitic microbes, causing diseases; indeed, Chagas' disease, widespread in tropical and temperate South America, is due to a flagellate, Trypanosoma cruzi, which also is a common parasite of many wild and domestic mammals.

Species accounts

List of Species

Greenhouse whitefly
Pea aphid
Giant water bug
Spittle bug
Seventeen-year cicada
Bed bug
Tomato bug
Water boatman
Delphacid treehopper
Unique-headed bug
Sea skater
Water measurer
Creeping water bug
Backswimmer
Moss bug
Southern green stink bug
Spiny soldier bug
Rhodesgrass mealybug
Staining bug
Kissing bug
Shore bug

Greenhouse whitefly

Trialeurodes vaporariorum

family

Aleyrodidae

taxonomy

Aleurodes vaporariorum Waterhouse, 1856, England.

other common names

English: Glasshouse whitefly; Spanish: Mosca blanca de invernaderos.

physical characteristics

Small, about 0.06 in (1.5 mm) long. Body and wings are powdered with white wax, which masks the yellowish to pale brown surface. Sexes are similar, both winged. Larvae scalelike and yellowish.

distribution

Cosmopolitan and intertropical; almost exclusively found in greenhouses in temperate zones.

habitat

Leaves (mostly on the underside) and twigs of a great variety of plants, including many cultivated ones.

behavior

First-instar larvae walk for a couple of hours and then fix the beak at the underside of a leaf and remain there through four molts. The last instar serves as a puparium, inside which the winged adult develops. Gregarious, mostly at the underside of leaves; adults fly quickly if disturbed.

feeding ecology and diet

Once the ambulatory first-instar larva finds a suitable place on a leaf, it buries its beak and starts feeding. Adults also suck sap but move around.

reproductive biology

Mating and egg laying take place on the plants. The yellow eggs are glued to the surface in curved rows; they turn black before hatching. Reproduction occurs year-round.

conservation status

Not threatened.

significance to humans

A serious pest in greenhouses. Large numbers reduce plant vigor. Sooty mold develops on the honeydew from adults and larvae, reducing marketability; some cultures must be abandoned.


Pea aphid

Acyrthosiphon pisum

family

Aphididae

taxonomy

Aphis pisum Harris, 1776. Type locality not specified.

other common names

English: Green alfalfa aphid; French: Puceron vert, puceron du pois; German: Grüne Erbsenblattlaus; Spanish: Pulgón verde de alfalfa; Italian: Afidone verdastro del pisello; Portuguese: Piolho verde da ervilla.

physical characteristics

Small, 0.08–0.16 in (2–4 mm) long. Wingless and winged individuals are light green, with red eyes. Antennae are slender and at least as long as the body. Legs long and slender. Wings, if present, are translucent. Abdominal siphons are long and slender. Larvae like small wingless adults.

distribution

Intertropical and temperate zones.

habitat

Canopy of leguminous weeds and shrubs. Prefer areas with alfalfa crops.

behavior

In winter they hide as wingless parthenogenetic females on leguminous shrubs. In spring, winged migratory individuals appear. Adults and young form dense patches.

feeding ecology and diet

Adults and larvae take sap from leaves, stems, and flowers of alfalfa, pea, bean, clover, and other crops.

reproductive biology

The species is permanently parthenogenetic in most temperate and subtropical zones, although in some areas one bisexual and many parthenogenetic generations alternate every year; females produce young, which in turn give off more young after a week.

conservation status

Not threatened. Control is achieved chiefly by parasitoid wasps.

significance to humans

It is adequately controlled in most countries, but it has been a serious pest of alfalfa crops.


Giant water bug

Lethocerus maximus

family

Belostomatidae

taxonomy

Lethocerus maximus De Carlo, 1938, Santa Cruz, Bolivia.

other common names

English: Giant electric light bug, giant toebiter, giant fishkiller; German: Riesenwasserwanze; Spanish: Chinche de agua gigante, cucaracha de agua gigante; Portuguese: Barata d'água gigante.

physical characteristics

The largest bug: adults can exceed 4.3 in (110 mm). Color an almost uniform grayish-brown; individuals may be darker or paler. Forelegs are robust, adapted for grasping prey; the middle and hind legs are flattened, adapted to swimming. Ventral parts covered with very short hairs that retain air for breathing, which is taken in by two extensible posterior appendices. Sexes alike. Larvae are like adults but smaller and wingless.

distribution

Tropical South America from the West Indies to northern Argentina.

habitat

Margins of pools and lakes, especially dam lakes, in the water among plants.

behavior

Prey, sometimes larger than the insects themselves, are grasped with the front legs, a poison is injected, and the digested tissues are sucked up. For taking in air, the giant water bug swims backward until the breathing appendages reach the surface. Courtship and egg laying have not been described. Males guard the eggs until they hatch. Dispersion flights occur at night, during which the bugs frequently are attracted to artificial lights.

feeding ecology and diet

A strong hunter of aquatic insects, fish, frogs, and tadpoles. Prey is killed by digestive saliva, and the liquefied tissues then are sucked up.

reproductive biology

Mating takes place in the water among plants; clusters of several dozens eggs are laid around a twig above the surface. Larvae disperse at hatching.

conservation status

Not threatened.

significance to humans

Predation on young fish may seriously constrain production in fish culture. Bites are very painful, but infrequent.


Spittle bug

Cephisus siccifolius

family

Cercopidae

taxonomy

Aphrophora siccifolia Walker, 1851, "West Africa" (probably erroneous).

other common names

English: Frog-hopper, froth bug, spittle-insect, cuckoo's spittle; Spanish: Cotorrita de la lluvia, cotorrita de las tipas.

physical characteristics

Elongated and anteriorly rounded, the hind portion acutely stretched. About 0.4–0.5 in (10–12 mm) long. Dull brown, with indefinite darker areas and minute whitish dots. Larvae are plumper, soft-bodied, and whitish with dark markings.

distribution

Mexico through Argentina and Uruguay.

habitat

Canopy of several trees, mainly Leguminosae, in dense and open forests. Adults are solitary and larvae gregarious, living in the abundant froth they produce. Common in parks and avenues of cities.

behavior

Adults fly frequently, mate, and search for egg-laying sites. As most homopterans do, spittle bug larvae quickly eliminate most of the water contained in the sap they consume. The water is excreted as watery feces, to which they add a thickening secretion and blow air bubbles into. The air bubbles produce a froth that builds up to form a large mass, which eventually begins to condense very slowly and produces drops that fall from

the canopy of trees to the ground. This process has given the bug its Spanish common name "cotorrita de la lluvia."

feeding ecology and diet

They feed on sap from twigs of trees; the amount removed is the highest known among the Homoptera.

reproductive biology

Mating occurs on twigs, in which the eggs are embedded in summer. Larvae hatch the next spring and develop quickly, reaching adulthood in a few weeks.

conservation status

Not threatened.

significance to humans

Abundant dropping of condensed froth sometimes causes trouble in cities.


Seventeen-year cicada

Magicicada septendecim

family

Cicadidae

taxonomy

Cicada septendecim Linné, 1758 Boreal America.

other common names

English: Periodical cicada, locust (this name should be restricted to grasshoppers); French: Cigale de dix-sept ans.

physical characteristics

Plump, 1.37–1.57 in (35–40 mm) long. Dull dark brown to black and shiny, with reddish eyes and legs. Wings transparent, with well-marked, reddish veins. Venter has broad orange stripes. Antennae very short and hairlike. Legs short, adapted for walking; when at rest wings extend far beyond the rear of the abdomen. Larvae almost colorless, living underground.

distribution

United States east of the Great Plains.

habitat

Canopy of deciduous trees, in temperate forests and rainforests.

behavior

Adults are diurnal. Males chirp loudly, attracting other males as well as females to the chorus. Larvae remain at the same site on a root for a long period of time and move stepwise to thicker roots as they grow and molt. At maturity they dig a tunnel to emerge. At sunset they emerge and molt to the adult form on stems. Most of every brood molts at the same time, thus appearing simultaneously in great numbers every 17 years at each location (but not always in the same year in distant locales).

feeding ecology and diet

Plants are pierced to suck liquid; adults feed from twigs and larvae from roots.

reproductive biology

The males' chirping attracts females, and mating occurs on stems in the end-to-end position. Eggs are embedded in plant tissues in the spring, up to twenty in each nest. Young larvae drop from the trees and burrow underground, searching for a suitable rootlet. They need 17 years to reach maturity.

conservation status

Not threatened, but destruction of the forests can affect populations.

significance to humans

If abundant on plantations, larvae are harmful to roots. End twigs replenished with eggs fail to grow the next season, especially in young trees. Choruses of cicadas may be annoyingly loud. The rigid periodical abundance is astonishing.


Bed bug

Cimex lectularius

family

Cimicidae

taxonomy

Cimex lectularius Linné, 1758, "Habitat in domibus exoticus, sed ante epocham salutarem in Europa, at in Anglia vix ante 1670 visus teste Southall" [It lives in exotic countries' housings, but before the healthful epoch in Europe, as it was seen in England somewhat before 1670, according to Southall].

other common names

English: Red coat, mahogany flat, wall louse; French: Punaise des lits; German: Bettwanze; Spanish: Chinche de cama; Portuguese: Percevejo de cama.

physical characteristics

Oval to round, very flat when not fed, globose and longer when fully fed. 0.16–0.19 (4–5 mm) long. Rusty brown to dull red. Rather short beak. Four-jointed antennae. Fore thorax roundly expanded around the rear of the head. Legs short. Flightless. Larvae look like small adults.

distribution

Almost cosmopolitan, including cold areas, but rare or absent in large parts of Asia because of hybridization with another species.

habitat

Human-made housings, mostly in bedrooms, crevices, bed frames, and mattresses or under wallpaper.

behavior

They creep from their shelters and walk among bedding and clothing to the host, biting to take the blood of resting humans. They avoid humid surfaces.

feeding ecology and diet

Adults and larvae hide in the daytime and emerge at night, searching for human blood; they also may feed on poultry, dogs, and bats. They can take a blood meal four to five times as heavy as themselves. Starving individuals survive a long time, more than a year in cold climates, but do not reproduce.

reproductive biology

Mating occurs in the shelters; the male mounts the female, puncturing her abdomen with his large clasper and discharging sperm into her cavity. Eggs are glued to any support at or near the bed. Young larvae start feeding soon.

conservation status

Not threatened.

significance to humans

Bed bugs were known in ancient Egypt and classical Greece. Rapid expansion of populations can be expected in crowded conditions. Bed bugs can transmit some microbial parasites. Biting itself is painless, but the saliva produces an uncomfortable itching. Some people used (and perhaps still use) bed bugs as a medicine.


Tomato bug

Phthia picta

family

Coreidae

taxonomy

Cimex pictus Drury, 1770, Meridional America.

other common names

English: Potato bug; Spanish: Chinche del tomate, chinche de la papa; Portuguese: Chupador do tomate.

physical characteristics

Elongate, reaching some 0.59 in (15 mm) in length. Its abdomen is nearly triangular in shape. Dark grayish brown to almost black, frequently with a transverse yellowish to orange cross stripe. Long and slender antennae and legs. Sexes alike. Larvae wingless, brightly colored, with silky, whitish areas.

distribution

Most of tropical and temperate America from southern United States (California through Florida) through Uruguay and central Argentina in lowlands.

habitat

The canopy of bushes and dense grasses; frequently seen on tomato and other solanaceous crops.

behavior

Adults are mostly solitary, moving about on plants and flying readily if disturbed. Larvae are gregarious, forming dense

groups, which remain for extended periods of time at the same place.

feeding ecology and diet

Adults and larvae take sap from shrubs and bushes, mainly from the unripe fruits; they prefer solanaceous species, but they are found on squash too.

reproductive biology

Mating occurs on the plants, in an end-to-end position. Some 20–40 pale yellowish eggs are glued to leaves, in straight rows, and become ochre in color. After hatching, larvae remain aggregated almost until the last instar. Three to five generations per year.

conservation status

Not threatened.

significance to humans

A minor pest, mainly of tomato crops; little effort is needed to control populations.


Water boatman

Sigara platensis

family

Corixidae

taxonomy

Sigara platensis Bachmann, 1962, Buenos Aires, Argentina.

other common names

None known.

physical characteristics

Elongate, some 0.24–0.28 in (6–7 mm) long. Dull brown, composed of very fine dark and pale vermiculate lines. Beak very short, not prominent. Forelegs spoon-shaped and adapted for sweeping small particles; middle legs long and very slender, adapted for anchoring to the bottom; hind legs extended to the sides like the oars of a boat, flattened, and with long hairs, adapted for swimming. Larvae similar to adults but much smaller and wingless.

distribution

Lowlands of southern South America, from central Bolivia, Paraguay, and southern Brazil to northern Patagonia, east of the Andes.

habitat

Shallow ponds and pools, especially rain pools, in water with few plants. A pioneer species.

behavior

Most of their time is spent at the bottom, anchored to the substrate. Every few minutes they loosen from the bottom, reaching the surface by buoyancy; take air very quickly; and return to the bottom by swimming. They leave habitats that are drying up, flying in search of another one. They are attracted en masse to artificial lights.

feeding ecology and diet

Small prey are swept up with the forelegs and pierced by the buccal stylets; digestive juices are injected, and once the contents are digested they are swallowed. Very small items can be ingested whole. Algae and detritus may be taken too.

reproductive biology

Courtship begins with loud chirping by the male, answered gently by the female, which orients the insects to each other. The male mounts the back of the female, bends his abdomen laterally, and mates with her from the right side. Eggs are glued to any support. Males soon die; adult proportions are usually biased toward females.

conservation status

Not threatened.

significance to humans

The appearance of masses of insects around artificial lights at night may be troublesome.


Delphacid treehopper

Delphacodes kuscheli

family

Delphacidae

taxonomy

Delphacodes kuscheli Fennah, 1955, Juan Fernández Islands, Chile.

other common names

Spanish: Cotorrita del maíz.

physical characteristics

Elongate, some 0.31–0.39 in (8–10 mm) long. Brownish to almost black, with a narrow yellowish stripe on the head. Forewings each have a black spot. Beak reaches the midlegs. Legs adapted for walking. Hind legs also adapted for jumping, as the ends of the tibiae contain conspicously flattened, denticulate spurs. Short-winged specimens are more common than winged ones. Sexes alike. Larvae resemble adults but are smaller and wingless.

distribution

Central Chile and central to northwestern Argentina, mainly in corn crop areas, up to an elevation of 6,562 ft (2,000 m).

habitat

On stems and blades of grasses.

behavior

Long-winged adults fly easily from grass to grass; all forms (both flying specimens and those that do not fly) and larvae walk along stems and blades and jump quickly if disturbed. Eggs are embedded in grass stems.

feeding ecology and diet

Larvae and adults suck sap from grasses, frequently of cereals.

reproductive biology

Mating takes place on grasses. Slots are cut into blades of grass and two eggs are embedded in each slot; if the blades are too tough to be cut, the bugs move onto softer grass.

conservation status

Not threatened.

significance to humans

An important cereal crop pest, causing heavy losses of yield, mainly by transmission of pathogenic viruses such as MRCud; this endemic disease is called "Mal de Río Cuarto del maíz" (Río Cuarto maize disease).


Unique-headed bug

Gamostolus subantarcticus

family

Enicocephalidae

taxonomy

Henicocephalus subantarcticus Berg, 1883, Isla de los Estados, Tierra del Fuego, Argentina.

other common names

English: Four-winged fly.

physical characteristics

Small, elongate, 0.24–0.31 in (6–8 mm) long. Dull yellowish to light brown in color. Prothorax is constricted twice, forming three lobes. Forelegs are thicker, adapted for grasping. Wings have somewhat reduced veins; both sexes are winged.

distribution

From southern tip of South America north to Osorno, Chile.

habitat

Hidden under stones in humid, cold-temperate forests.

behavior

Nothing is known.

feeding ecology and diet

Generalized predator on small prey.

reproductive biology

Little is known. Both sexes form dense swarms. Mating has not been observed. Eggs probably are laid in shelters.

conseztion status

Not threatened.

significance to humans

None known.


Sea skater

Halobates micans

family

Gerridae

taxonomy

Halobates micans Eschscholtz, 1822, southern Pacific and Atlantic Oceans.

other common names

English: Sea water-strider.

physical characteristics

Plump, with a very short abdomen. About 0.16–0.18 in (4.0–4.6 mm) long. Body is dull brown to black with a very fine silvery coating; there is a pair of yellow marks on the head. Antennae are long. Forelegs short; middle and hind legs very long and slender. Wings absent.

distribution

Intertropical zones of all oceans, ranging to temperate latitudes.

habitat

The open ocean surface.

behavior

They skate swiftly on the water surface, with the aid of a fringe of hair on the middle legs. Behavioral adaptations to the open ocean life may include a means of communication between individuals, to keep the population in one place.

feeding ecology and diet

Adults and larvae feed on planktonic microcrustaceans and fish larvae trapped in the surface film, and on floating jellyfish.

reproductive biology

Mating and egg laying occur at the surface; the laying site may be any floating object, such as bird feathers, seaweed, timber, cork, coal, shells of cuttlefish, tar lumps, or even the feathers of living seabirds; eggs often are found attached in great numbers. There are five larval instars.

conservation status

Not threatened.

significance to humans

None known.


Water measurer

Hydrometra argentina

family

Hydrometridae

taxonomy

Hydrometra argentina Berg, 1879, Buenos Aires, Argentina.

other common names

English: Marsh treader, walking water-stick.

physical characteristics

Slender and cylindrical with a very long head, the eyes placed midway along its length. About 0.39 in (10 mm) long. Uniformly pale brown. Antennae and legs are very slender. Long-winged, short-winged, and wingless individuals coexist. Sexes are alike. Larvae resemble adults but are much smaller and wingless.

distribution

Lowlands of most of South America on both sides of the Andes but not in Patagonia.

habitat

Surface of ponds and dead waters of small brooks, without plants or with a few plants.

behavior

They walk slowly on the water surface in the daytime, searching for prey or for a mate. Long-winged individuals disperse by flight and are attracted to artificial lights.

feeding ecology and diet

Adults and larvae feed on small insects, aquatic or not—mainly those blown onto the water surface.

reproductive biology

Mating takes place on the water surface. Large, elongated, ornamented eggs are glued singly to emerging sticks.

conservation status

Not threatened.

significance to humans

Perhaps controls populations of mosquito larvae.


Creeping water bug

Ilyocoris cimicoides

family

Naucoridae

taxonomy

Nepa cimicoides Linné, 1758, Europe.

other common names

English: Saucer water bug, water bee; German: Schwimmwanze.

physical characteristics

Rounded, oval, and beetle-like, reaching 0.59 in (15 mm) in length. Dull green, with somewhat darker forewings. Beak is short and conical. Forelegs very robust, adapted for grasping prey; middle and hind legs have long swimming hairs. Venter is covered by air-retaining hairs. Sexes are alike. Larvae resemble adults but are much smaller and wingless.

distribution

Southern Palearctic region, from southern Britain and the northern Iberian Peninsula eastward through China.

habitat

Freshwater ponds among submerged plants.

behavior

They swim swiftly around. Males chirp to attract females. They lie in ambush, awaiting and quickly attacking prey.

feeding ecology and diet

Adults and larvae prey on insects and snails. Prey is killed with a poison injected with the beak and is sucked empty.

reproductive biology

Mating occurs on the bottom or on supports in the water. The male mounts the back of the female, grasps her with the forelegs and middle legs with his axis at a slight angle to hers, and copulates at the left side of her abdomen. Eggs are embedded in rows into stems or leaves.

conservation status

Not threatened.

significance to humans

They readily bite if carelessly handled; bites are extremely painful. They may be a nuisance to fish fry in fishery ponds.


Backswimmer

Notonecta sellata

family

Notonectidae

taxonomy

Notonecta sellata Fieber, 1851, Buenos Aires, Argentina.

other common names

None known.

physical characteristics

Spindle shaped and somewhat rounded in front; some 0.31–0.35 (8–9 mm) in length. Typically marked with dark blue and white, but colorless specimens occur. Beak is short and conical. Front and middle legs are rather short; hind legs are very long, extended to the sides like the oars of a boat and with long hairs adapted for swimming. Larvae are similar to adults but smaller and wingless.

distribution

Lowlands of southern South America from central Bolivia, Paraguay, and southern Brazil to northern Patagonia east of the Andes.

habitat

Shallow ponds and pools, especially rain pools, in water with few plants. Prefers turbid water.

behavior

They swim slowly, always on their backs near the surface, searching for prey, but they escape very quickly if disturbed. They fly away from pools that are drying up. Often attracted to electric lights.

feeding ecology and diet

A generalist predator on small insects and crustaceans in the upper water layers. Prey is seized and held by the front and middle legs.

reproductive biology

Mating takes place near the surface of the water, males mounting the (downturned) backs of females. Eggs are glued singly to submerged supports, such as twigs and even algal filaments. There are five larval instars.

conservation status

Not threatened.

significance to humans

Some damage to fish fry may be expected in fish ponds. Perhaps controls populations of mosquito larvae.


Moss bug

Peloridium hammoniorum

family

Peloridiidae

taxonomy

Peloridium hammoniorum Breddin, 1897, Navarino Island (Tierra del Fuego), Chile.

other common names

None known.

physical characteristics

Small and flat, 0.16–0.19 in (4–5 mm) long. Dull colored, cryptic on mosses. Head and prothorax are expanded laterally. Forewings have coarse reticulation. Short-winged specimens are more common than winged ones.

distribution

From the southern tip of South America north to Chubut Province (Argentina) and Aysén (Chile).

habitat

Humid forests on the moss Polytrichum strictum.

behavior

Almost nothing is known. Found quiescent or climbing among mosses.

feeding ecology and diet

Feed on liquids they suck from mosses.

reproductive biology

Mating has not been studied. The smooth-shelled eggs are laid on mosses. Larvae cohabit with adults.

conservation status

Not threatened.

significance to humans

None known.


Southern green stink bug

Nezara viridula

family

Pentatomidae

taxonomy

Cimex viridulus Linné, 1758, "Indiis" (may mean India, Southeastern Asia, or the East Indies).

other common names

English: Southern green bug, green vegetable bug, tomato bug, bean bug; French: Punaise verte; Spanish: Chinche verde; Portuguese: Percevejo verde.

physical characteristics

Broad and medium sized, 0.47–0.51 in (12–13 mm) long. Green, with dark red eyes. Other forms may be green with a yellowish collar, pink, golden, or liver brown. Antennae have five joints. All the legs are about the same shape and size, and adapted for walking. Basal part of the forewing is stiff; the distal one is translucent. Sexes are alike. Larvae wingless and brightly stained with red, yellow, white, or black.

distribution

Temperate and tropical zones of both hemispheres, but not in very cold and desert areas. Worldwide spread started some 250 years ago from an uncertain origin, perhaps eastern Africa or the Far East.

habitat

Canopy of many field and ornamental crops and weeds.

behavior

Active mainly in the daytime, climbing to the canopy early in the morning; egg laying is mostly a nocturnal activity. Newly born larvae remain densely grouped; adults are solitary, flying readily if disturbed.

feeding ecology and diet

Sap is sucked from leaves, twigs, buds, growing shoots, flowers, and fruits; succulent parts are preferred. The list of food plants includes more than 80 species from more than 30 families; the species is a generalist. First-instar larvae do not feed.

reproductive biology

Mating occurs on plants, with the partners in an end-to-end position. Egg batches with 30–130 (average 70–75) drum-shaped, yellowish eggs in several rows are glued to the under-sides of leaves; they turn pink and then red-orange. Females lay one or two egg batches. Up to five generations per year in warm climates but fewer in temperate areas.

conservation status

Not threatened.

significance to humans

Severe damage is done in several cultures, with yield loss and damage to quality; viruses and disease-producing fungi are transmitted. Much effort is invested in controlling these pests. Adults are controlled mainly by species of parasitic flies; eggs are efficiently controlled (95%) by tiny wasps.


Spiny soldier bug

Podisus maculiventris

family

Pentatomidae

taxonomy

Pentatoma maculiventris Say, 1831, Louisiana, United States.

other common names

English: Spiny predator stink bug.

physical characteristics

Elongate, about 0.35–0.55 in (9–14 mm) long. Dull yellow to tan with small black punctures and a dark spot at the rear; sometimes marked with purplish-red. Fore thorax with a prominent spine on each "shoulder." Antennae are five-jointed. All the legs are about the same shape and size, and adapted for walking. Basal part of the forewing is stiff; the distal one is translucent. Sexes are alike. Larvae are broader, wingless, and dotted with red, cream, and black.

distribution

Temperate North America and the West Indies; introduced for pest control to European and Far East countries.

habitat

Canopy of trees and shrubs, several field crops, fruit orchards.

behavior

Diurnal, surveying on foot the canopy of plants and searching for prey and egg-laying sites. Prey is located by sight, and tracks are followed with the antennae and beak. Adults fly quickly when disturbed. Young larvae are gregarious, dispersing progressively as they grow and molt; they quickly walk from plant to plant. A secretion produced by males attracts all instars acting as a cue to the presence of prey. Hibernation in litter, soil, or bark or under stones.

feeding ecology and diet

Adults and larvae prey mainly on caterpillars and beetle larvae but also on eggs, sucking them out; this is a fairly generalist species. Densely hairy caterpillars are avoided, but size of prey is unimportant. If prey items are bigger than the insects themselves, they slowly approach the prey, extend their beak forward, and pierce it from the side without touching it with their legs. Attacks sometimes are accomplished collectively, and other insects may come to share an already attacked prey item. If food is scarce, cannibalism occurs. Some water or juices are taken; if prey are scanty, they can survive a long time.

reproductive biology

Mating occurs in the end-to-end position on plants and lasts many hours. Some 15–30 cream to black, barrel-shaped eggs are glued onto leaves in loose oval patches. They reproduce throughout their lifetime, which may last several months. Two or three generations per year are produced in temperate zones, but continuous reproduction takes place in warmer ones.

conservation status

Not threatened.

significance to humans

Useful controllers of pests, chiefly the Colorado potato beetle and caterpillars. Reared to be released in the field. Their powerful pheromone is produced commercially to attract specimens to orchards. A light and uncomfortable irritation may occur on human skin, but true bites have not been reported.


Rhodesgrass mealybug

Antonina graminis

family

Pseudococcidae

taxonomy

Sphaerococcus graminis Maskell, 1897, Hong Kong.

other common names

English: Grass-crown mealybug, felted grass coccid, Rhodes-grass scale.

physical characteristics

Ellipsoid to nearly spherical and about 0.11–0.16 in (3–4 mm) long. Purplish brown and covered dorsally by a felted, waxy, brittle, whitish to yellowish coating. Openings at the anterior and posterior ends expose the body, with a tubular, waxy white filament protruding from the anal end. First larval instar is ambulatory; the remaining instars and adults are legless.

distribution

Of Asiatic origin but now almost cosmopolitan, chiefly in warmer parts of temperate zones.

habitat

Crown, base, leaf sheaths, and stolons of forage grasses and lawns.

behavior

The first instar larva walks and changes resting sites; thereafter, they are legless and remain in place for life, soon starting to secrete their felted, waxy coating.

feeding ecology and diet

Adults and larvae take sap from several grasses, chiefly cereals. Newly born larvae walk around and set themselves down in a leaf sheath, engaging in active feeding until death.

reproductive biology

Parthenogenetic, without males. The female produces living larvae; only newly born larvae walk. There are about five generations per year.

conservation status

Not threatened.

significance to humans

A minor pest of field crops. Yield losses can be expected in cereal cultures, as well as withering of lawns. The sugary feces favor sooty mold development.


Staining bug

Dysdercus albofasciatus

family

Pyrrhocoridae

taxonomy

Dysdercus albofasciatus Berg, 1878, Corpus, Misiones Province, Argentina.

other common names

English: Cotton bug, cotton stainer; Spanish: Chinche negra (general), chinche guacha (general), chinche tintórea (Uruguay), chinchorro (Ecuador), churumbo (Peru); Portuguese: Barbeiro, percevejo manchador.

physical characteristics

Nearly oval and elongate. Back is black, with a transverse whitish-yellowish stripe; venter is bright red. Antennae and legs are long and slender. Larvae smaller, wingless, bright red.

distribution

Tropical South America, following the distribution of their host plants.

habitat

Canopy and flowering and fruiting twigs of malvaceous shrubs.

behavior

Adults are mostly solitary; larvae often are gregarious. Adults fly readily if disturbed.

feeding ecology and diet

Both adults and larvae prefer maturing or mature seeds; they inject saliva into them and suck the resulting liquid. When no fruits are available, they go to flowers, buds, or growing twigs.

reproductive biology

They mate end to end. Eggs are laid on twigs or leaves. Larvae aggregate at the site and disperse progressively as they grow and molt.

conservation status

Not threatened.

significance to humans

An uncommon secondary pest of cotton crops.


Kissing bug

Triatoma infestans

family

Reduviidae

taxonomy

Reduvius infestans Klug, 1834, South America.

other common names

English: Bloodsucking conenose; Spanish: Vinchuca (Bolivia, Paraguay, Chile, Argentina, and Uruguay), Chinchorro (Ecuador), Churumbo (Peru), Chinche negra, Chinche gaucha; Portuguese: Barbeiro.

physical characteristics

Flat when unfed and globose when fully fed. Grows to 0.83–1.18 in (21–30 mm) long. Dark brown to almost black, with yellow square spots along the abdominal margins; legs somewhat paler and wings dark brown. Head long and cylindrical. Compound eyes are large and set nearer the base of the head; also a pair of prominent simple eyes. Antennae and legs are long and slender. Sexes similar. Larvae look like adults but are smaller, dull grayish brown, and wingless.

distribution

Most of tropical and temperate South America south of the equator, from northern Brazil and Ecuador through Patagonia (southern Argentina) up to an elevation of 13,123 ft (4,000 m); their distribution is linked to the movement of humans with baggage.

habitat

Human dwellings and poultry yards. Forest populations apparently are rare. Even if straw roofs or crevices are smoked—a process that repels most insects—the insects are still able to sustain their colony.

behavior

Adults chirp by scraping the end of the beak against a ventral, transversely furrowed sulcus at the breast, the vibration being transmitted via the legs to the substrate. They orient themselves to their prey by heat and emission of carbon dioxide and to their shelters by the smell of their own excreta. Sleeping humans often are reached by flying. Adults may live two years.

feeding ecology and diet

Nocturnal, feeding on hosts as they sleep. They may feed on domestic animals, such as dogs and poultry. One blood supply is needed at each larval instar to reach adulthood.

reproductive biology

Mating occurs in shelters. The whitish eggs drop to the ground and change to pink. There is one generation per year.

conservation status

Not threatened.

significance to humans

An efficient transmitter of Chagas' disease. People believe that having kissing bugs in the home will bring good luck and happiness, a belief that interferes with sanitary control measures.


Shore bug

Saldula coxalis

family

Saldidae

taxonomy

Acanthia coxalis Stål, 1873, Cuba.

other common names

None known.

physical characteristics

Small, reaching 0.14–0.16 in (3.5–4 mm) in length; broad and flattened. Color varies widely from light to dark brown, mottled; lateral margins of pronotum are pale. Dorsum densely covered with short hairs. Legs are short, robust, adapted for walking and jumping. Wings complete or partially reduced (proportions of morphs vary). Forewings have well-marked veins and translucent membranes. Larvae are like adults but much smaller and wingless.

distribution

Texas (United States) through Chile and Argentina and the West Indies, principally along coasts; lives at elevations up to 11,480 ft (3,500 m) in Peru.

habitat

Salty, brackish, and freshwater swamps and muddy beaches of seas, lakes, and rivers; at floodtide they climb on grasses. Hardly seen on the mud and seldom collected.

behavior

They walk, run, or jump quickly on the soil and fly readily if disturbed. Much time is spent grooming the legs and antennae.

feeding ecology and diet

They feed on dead insects on the soil or drive the beak into the surface mud and suck out small invertebrates such as insect larvae and small earthworms.

reproductive biology

At mating the male positions himself side by side with the female, grasping her ovipositor with the claspers. Eggs are laid on grass blades; they can withstand drowning. Reproduction occurs year-round.

conservation status

Not threatened.

significance to humans

None known.


Resources

Books

Andersen, Nils M. The Semiaquatic Bugs (Hemiptera, Gerromorpha): Phylogeny, Adaptations, Biogeography, and Classification. Entomonograph 13. Klampenborg, Denmark: Scandinavian Science Press, 1982.

Schaefer, Carl W. "Prosorrhyncha (Heteroptera and Coleorrhyncha)." In Encyclopedia of Insects, edited by V. H. Resh and R. T. Cardé. Amsterdam: Academic Press, 2003.

——, ed. Studies on Hemipteran Phylogeny. Thomas Say Publications in Entomology. Lanham, MD: Entomological Society of America, 1996.

——. "True Bugs and Their Relatives." In Encyclopedia of Biodiversity, vol. 5. San Diego: Academic Press, 2000.

Schaefer, Carl W., and A. R. Panizzi, eds. Heteroptera of Economic Importance. Boca Raton, FL: CRC Press, 2000.

Schuh, R. T., and J. A. Slater. True Bugs of the World (Hemiptera: Heteroptera): Classification and Natural History. Ithaca, NY: Cornell University Press, 1995.

Periodicals

Evans, J. W. "A Review of Present Knowledge of the Family Peloridiidae and New Genera and Species from New Zealand and New Caledonia (Hemiptera: Insecta)." Records of the Australian Museum 34, no. 5 (1981): 381–406.

Wheeler, W. C., R. T. Schuh, and R. Bang. "Cladistic Relationships among Higher Groups of Heteroptera: Congruence between Morphological and Molecular Data Sets." Entomologia Scandinavica 24 (1993): 121–137.

Other

"Fulgoromorpha Lists on the Web." November 30, 1999 [May 12, 2003]. <http://flow.snv.jussieu.fr/>.

"Halobates—Oceanic Insects." June 26, 2002 [May 12, 2003]. <http://www.zmuc.dk/EntoWeb/Halobates/HALOBAT1.HTM>.

"The International Heteropterist's Society." January 3, 2002 [May 12, 2003]. <http://entomology.si.edu/ihs/home.lasso>.

"Periodical Cicada Page." December 16, 2002 [May 12, 2003]. <http://insects.ummz.lsa.umich.edu/fauna/Michigan_Cicadas/Periodical/Index.html>.

"Scale Net." March 19, 2003 [May 12, 2003]. <http://www.sel.barc.usda.gov/scalenet/scalenet.htm>.

"Whitefly Taxonomic and Ecological Website." November 5, 2002 [May 12, 2003]. <http://www.fsca-dpi.org/Homoptera_Hemiptera/Whitefly/whitefly_catalog.htm>.

Axel O. Bachmann, Doctor en Ciencias Biológicas

Silvia A. Mazzucconi, Doctor en Ciencias Biológicas