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Arthropoda: Insecta

HEMIPTERA KEY

(True Bugs)

(Contact)

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[Also see: <Hemiptera Details>]

Originally the Insect Order Hemiptera was divided into two suborders: Heteroptera and Homoptera. Since the latter part of the 20th Century the Homoptera, which are almost wholly plant feeders were elevated to full order status, but their members are of little medical significance. Although the Hemiptera also are plant feeders there are some species that reed on the blood of other insects and can attack animals and humans as well. The main structural characters are two pairs of wings (in most species), with the forewings being thickened at their bases (hemelytra). The hind wings are very thin and have few veins. The mouthparts include a beak that extends from the front part of the head and is jointed. Metamorphosis is gradual, with young individuals appearing as miniature adults.

Hemiptera families or subfamilies of primary medical importance are:

Anthocoridae, Belostomatidae, Cimicidae, Coreidae, Lygaeidae, Miridae, Nabidae, Notonectidae, Piratinae, Pyrochorridae, Reduviidae, Reduviinae, Triatominae.

The following key separates the important families that attack humans and animals

by biting and/or vectoring diseases:

1. Antennae are shorter than the head and hidden in a depression beneath the head and eyes. All species are aquatic _ _ _ _ _ _ 2

The antennae are exposed and as long or longer than the head_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 3

2. The hind tarsi have two segments, the last one having two claws. These are large flat bugs. The forewing has distinct veins in

the membranous (giant water bugs) _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Belostomatidae

Hind tarsi have 3 segments, the first being quite short and indistinct. The tarsal claws are seriform. The head is inserted deep

into the prothorax (back swimmers, boat shaped bugs) _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Notonectidae

3. The beak has three segments _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 4

The beak has four segments _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 6

4. The beak is solid and lies in a cross-striated groove but does not extend to the middle coxae. When ocelli are present they occur

behind the eyes or a transverse depression (assassin bugs) _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Reduviidae [Subfamilies: 10

The beak is elongated and reaches to the middle coxae; the groove is not cross striated. The ocelli if occurring are not situated as

noted previously _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 5

5. Ocelli are absent. The forewings are reduced and without a membrane or vestigial (bedbugs) Male abdomen narrows from 3rd

segment to a pointed tip, while in female there is less narrowing and tip is rounded (Fig. 1) _ _ _ _ _ _ _ _ _ _ _ Cimicidae

Ocelli are present. The forewings are usually well developed. A embolium is present (Fig. 2). The membrane of the forewings

has no veins or very indistinct veins (flower bugs) _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Anthocoridae

6. The front legs are adapted for seizing prey. The fore tibiae and often the front femora are armed with stout interlocking spines

_ _ __ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Nabidae

The front legs are adapted only for walking _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 7

7. The front wings have a U-shaped segment (the cuneus) at the apex of the hardened wing base. The wing membrane has one or

two closed cells (leaf bugs) (Fig. 3) _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Miridae

The front wing are quite different from the previous description _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 8

8. Ocelli are not present (cotton stainers) _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Pyrochorridae

Ocelli are present, and there are no transverse depressions in front of the ocelli _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 9

9. The forewing membrane has 5 simple veins that arise from its base (chinch bugs) _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Lygaeidae

The forewing membrane has many, often anastomosing, veins that originate from the transverse basal vein (squash bugs)

(Fig. 4)._ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Coreidae

Subfamilies of REDUVIIDAE

10. The beak is divided into 3 segments. It fits into a cross_striated groove and is stout, short and does not reach the middle coxae.

Ocelli, when present, are located clearly behind the eyes or behind a transverse depression (Reduviidae) _ _ _ _ _ _ _ 11

11. The wing membrane has one or more closed cells. The front coxae are not much elongated and usually less than 2_times

as long as broad, but not extending past the head apex _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 12

12. The pronotum is constricted behind the middle. Ocelli are present (Melanolestes, Rasahus, etc.) _ _ _ _ Piratinae-1,

Piratinae-2, Piratinae-3

The pronotum is constricted at or near the middle _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 13

13. Ocelli are present and situated behind the compound eyes. The 2nd segment of the antenna is not subdivided _ _ _ _ _ _ _ 14

14. The elongated head is hardly ever constricted behind the eyes. The ocelli are located on oblique rises or tubercles at the

posterolateral angles of the long, cylindrical head. Dorsal abdominal glands are absent (Psammolestes, Rhodnius,

Eratyrus, Panstrongylus, Triatoma, etc.) _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Triatominae

The head is transversely constricted behind the eyes. The eyes are not stalked. The antennae are not inserted on long, oblique

tubercles. Dorsal scent glands are present (Reduvius, Spiniger, etc.) _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Reduviinae

_ _ _ _ _ _ _ __ _ _ _ _ _ _ _ _ _ _ _

Key References: <medvet.ref.htm> <Hexapoda>

Chinery, M. 1993. Insects of Britain and Northern Europe 3rd ed..

Cohen, Allen C. 1990. Feeding Adaptations of Some Predaceous Hemiptera. Ann. Ent. Soc. Amer. 83 (6): 1215–1223.

Coll, M.; Ruberson, J.R. (eds.) 1998. Predatory Heteroptera: their ecology & use in biological control. CAB Direct Org.

Czarkowska, J. & S. Blank-Weissbeg. 1930. The role of the bedbug (Cimex lectularius) in the transmission of relapsing fever. Warsaw Rev.

Appl. Ent (B): 18.

Daly, H. V., John T. Doyen & Alexander H. Purcell 1998. Introduction to Insect Biology and Diversity 2nd ed.. Oxford University Press. pp. 320.

Foltz, J. L. January 23, 2003. "ENY 3005 Families of Hemiptera". University of Florida..

Forero, Dimitri. 2008. The Systematics of Hemiptera. Revista Colombiana de Entomologia. 34(1): 1–21.

Goddard, Jerome. 2009. Bed Bugs (Cimex lectularius) & clinical Consequences of their bites. JAMA. 301 (13): 1358–1366.

Goddard, J. & R. deShazo. 2009). "Bed bugs (Cimex lectularius) and clinical consequences of their bites". J. Amer. Med. Assoc. 301(13): 1358–66

Hagler, J. "Geocoris spp. Heteroptera: Lygaeidae – Bigeyed Bug". In Catherine R. Weeden, Anthony M. Shelton & Michael P.

Matheson, R. 1950. Medical Entomology. Comstock Publ. Co, Inc. 610 p.

Service, M. 2008. Medical Entomology For Students. Cambridge Univ. Press. 289 p

Legner, E. F. 1995. Biological control of Diptera of medical and veterinary importance. J. Vector Ecology 20(1): 59-120.

Legner, E. F. 2000. Biological control of aquatic Diptera. p. 847-870. Contributions to a Manual of Palaearctic Diptera,

Vol. 1, Science Herald, Budapest. 978 p.

Reinhardt, Klaus & M. T. Siva-Jothy. 2007. Biology of the bed bugs (Cimicidae). Ann. Rev. Ent. 52: 351–374.

Ruppert, Edward E., R. Fox, S. Richard, & R. D. Barnes. 2004. Invertebrate Zool., 7th edition. Cengage Learning. pp. 728, 748.

Shcherbakov, D. E. 2000. "Permian faunas of Homoptera Hemiptera in relation to phytogeography and the Permo-Triassic crisis" PDF.

Paleontological Journal 34 3: S251–S267

Usinger, W. E. 1944. The Triatominae of North and Central America and the West Indies and their public health significance. U. S. Pub

Hlth. Serv. Bull 288.

Yorke, W. 1937. Chagas' disease: a critical review. Trop. Dis. Bull. 34: 275-300.

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