File: <dipterafamilykey.htm> <Medical Index> <General Index> Site Description Glossary <Navigate to Home>

 

 

Arthropoda: Insecta

KEY TO FAMILIES OF DIPTERA

(Flies, Gnats & Mosquitoes)

(Contact)

 

 

Please CLICK on underlined links to view images or to navigate within the key:

To Search for Subject Matter with Microsoft Explorer use Ctrl/F within links.

 

There are two suborders in the family: Orthorrhapha and Cyclorrhapha. The Orthorrhapha have pupae that emerge from the last larval skin through a T-shaped slit near the anterior end or by a slit between the 7th and 8th abdominal segments. Most larvae have a small but well formed head. The pupa is never enveloped in a final skin of Fig. 1). Flies of the Cyclorrhapha group have pupae that are enclosed in the last larval skin, which is called the puparium. Adults emerge by using a ptilinum to cut a round opening at the anterior end of the puparium. Adults have a frontal lunule that is set off by a suture (Fig. 2). The wings have a more complicated venation (e.g., Calliphora sp.).

[Also see: Diptera Details]

 

Diptera families or subfamilies that contain species of medical importance because

of their annoyance, biting habits or as vectors of disease include:

 

Calliphoridae, Ceratopogonidae, Chironomidae, Chloropidae, Culicidae, Dixidae, Drosophilidae, Gasterophilidae, Heleidae, Hippoboscidae, Muscidae, Nycteribiidae, Oestridae, Phlebotominae, Phoridae, Piophilidae, Psychodidae, Psychodinae, Rhagionidae, Sarcophagidae, Sepsidae, Simuliidae, Streblidae, Syrphidae, Tabanidae, Tachinidae.

 

Following are keys to adults and larvae of the principal families of Diptera of medical importance to humans:

 

 

DIPTERA ADULTS

 

 

1. Flies have a leathery texture. Adults are blood sucker ectoparasites on birds and mammals. Winged and wingless or vestigial

winged species are present. The abdomen is not clearly divided into segments. The antennae are short and inserted into small

rather obscure pits (e.g., Pupipara group of flies) _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 2

 

Flies are quite different from the previous description. The abdomen is clearly segmented. Adults are never external parasites

on birds or mammals. The antennae are not inserted into pits and are generally quite visible. Only one pair of wings is

typically present _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 4

 

2. The head is small and narrow. It is folded back in a groove on the thorax. Species are wingless (Parasites of bats) _ _ _ _ _ _ _

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Nycteribiidae

 

The head is not as previously described but is in a more normal position _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 3

 

3. The palpi re elongated and form a sheath for the piercing mouthparts. Most species are winged with the veins clumped up

anteriorly. Species are parasitic on birds and mammals _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Hippoboscidae

 

Palpi are broad and leafy and do not form a sheath for the mouthparts _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Streblidae

 

4. The antennae have eight or more movable almost similar segments. The anal wing cells (Fig. 3) are wider toward the margin.

Flies of the Nemotocera group _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 5

 

Antennae without more the 4 or 5 segments. The segment beyond 2nd one may appear as a consolidated ring or annuli _ _ 9

 

5. The wing's costal vein does not continue beyond the apex. Hairs and scales on the wing are rarely present (Fig. 4) _ _ _ _ 6

 

The costal vein surrounds the wing. Hairs on the wing are frequently dense or scales are present particularly on the costa and

posterior margins _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 8

 

6. The antennae are shorter than the thorax and have 10 or 11 closely cohesive and similar segments. They are never feathery.

The legs are strong with the hind pair somewhat widened. The body is stocky. The wings are broad with few veins (black flies)

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Simuliidae

 

Antennae are longer than the thorax and usually bushy with long hairs. Otherwise dissimilar from above _ _ _ _ _ _ _ _ _ _ 7

 

7. The dorsal part of the thorax has a longitudinal groove. The wings are narrow and held rooflike. Mouthparts are adapted for

piercing (gnats that are only annoying nuisances but otherwise not of medical importance) _ _ _ _ _ _ _ _ _ Chironomidae

 

There is no longitudinal groove on the thorax dorsum. Wings are held flat and superimposed over one another when at rest.

Wings are often spotted (Fig. 153). Mouthparts are adapted for piercing (punkies) _ _ _ _ Heleidae & Ceratopogonidae

 

8. Flies are small and appear like moths. The mouthparts are very short. The wings and body are clothed with long hairs.

Wings have parallel veins, but scales are absent _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Psychodidae

 

8b. The Wing's 2nd longitudinal vein has 3 branches, the 3rd branch begins near the base (Fig. 5). (Of no medical importance) _ _

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Subfamily: Psychodinae

 

8c. The 2nd longitudinal vein has 3 branches, but the 3rd branch begins near the middle of the wing (Fig. 88) (Considerable

medical importance) _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Subfamily: Phlebotominae

 

Flies are not moth like. The posterior wing margin and most veins have coarse scales (Fig. 3). The mouthparts are elongated,

slender and well adapted for piercing in most species (mosquitoes) _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Culicidae

 

8d. Long-legged flies similar to Culicidae in wing venation but without scales. Scales also absent on body and legs. Mouthpart

s are not adapted for piercing _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ __ Dixidae

 

9. Antennae have 4 or 5 segments, and the segment beyond the 2nd may be formed into 3-8 rings. Squamae are large (horseflies)

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Tabanidae

 

Antennae have only three segments _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 10

 

10. The final antennal segment is small and ends in an elongated style or arista (Fig. 6) (snipe flies) _ _ _ _ _ _ Rhagionidae

 

Final antennal segment is much larger than the others and has a dorsal arista that is either bare or feathery (Fig. 7) _ _ 11

 

11. Wings have stout 2-3 stout veins near the inner costal border. Other veins are weak and extend outward to the wing margin.

Cross veins are absent _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Phoridae

 

Wings are different and not with stout veins _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 12

 

12. The wing anal cell is elongated reaching almost to the wing margin. A false vein is present between the 3rd and 4th

longitudinal veins. Species are often brightly colored (flower-loving flies (Fig. 8) _ _ _ _ _ _ _ _ _ _ _ _ _ _ Syrphidae

The anal cell is short and truncated (Fig. 9). A false vein is absent _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 13

 

13. The 2nd antennal segment has a longitudinal suture on its upper outer edge (Fig. 7-ds). Squamae are often conspicuous.

The Thorax usually has a transverse suture _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 14

 

The 2nd antennal segment does not have a longitudinal suture. Squamae are usually small and the thorax does not have a

complete transverse suture generally _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 18

 

14. The mouthparts are vestigial (warble & bot flies including Cuterebridae & Hypodermatidae _ _ _ _ _ _ _ _ _ _ _ Oestridae

 

Mouthparts are well developed and functional _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 15

 

15. The hypopleura do not have a well developed row of bristles below the posterior spiracle (Fig. 10). Small hairs may be

present. Antennal arista hairy or feathery usually (house-, stable- and tsetse flies) _ _ _ _ Muscidae & Anthomyiidae

 

The hypopleura do have a well-developed row of bristles (Fig. 10) or bristle tuft _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 16

 

16. The postnotum and postscutellum show a double ripple effect under the scutellum when viewed laterally. Species are usually

have many bristles. The larvae are all parasitic on other insects primarily _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Tachinidae

 

The postscutellum is not very well developed, and therefore only a single postnotum is visible laterally_ _ _ _ _ _ _ _ _ _ _ 17

 

17. All species are colored either metallic, blue, black or shades of green. Several species are not metallic but instead have

golden hairs on the thorax among the bristles (Pollenia spp.). There are often 4 notopleural bristles present (blowflies)

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Calliphoridae 1

 

Most flies are colored gray, silvery or a mix with darker colors. There are rarely more than 2 notopleural bristles (flesh flies) _ _ _ _ _

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Sarcophagidae 1

 

18. The mouthparts are vestigial and occur within tiny oval pits. They are large, brownish and fuzzy flies (horse botflies,

Fig. 11) _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Gasterophilidae

 

Mouthparts are well developed and not occurring in pits _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 19

 

19. The wing's subcosta is vestigial, but if present then it extends just a short distance beyond the humeral cross vein and not

reaching the costs _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 20

 

An existant subcosta extends to the costa, but is difficult to see as it is hidden underneath the 1st longitudinal vein _ _ _ 21

 

20. The 6th longitudinal and anal veins are absent. The ocellar triangle is large when compared with the head. The subcosta

appears as a tiny fold at its base. The costa has only one fracture (Fig. 12) Tiny flies (eye gnats) _ _ _ _ _Chloropidae

 

The 6th longitudinal vein and often the anal vein are present. The subcosta is more apparent but does not extend to the costa.

The costa has two fractures (fruit flies) _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Drosophilidae

 

21. The palpi are vestigial. Species are small and shiny black, brown or reddish with few bristles. The head is spherical and the

abdomen shaped like that of a wasp _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Sepsidae

 

Palpi well developed. Species all small in size but of a different shape from previous (cheese skipper) _ _ Piophilidae

 

= = = = = = = = = = = = = = = = = = = = = =

 

1/ Calliphoridae and Sarcophagidae are show here although some specialists may assign them to different groups. The names are common in the medical literature especially because they include important genera affecting humans and animals.

 

 

DIPTERA LARVAE

 

 

22. The larval head is well developed, not retractile and enclosed in a solid capsule. The mouthparts are normal, with the

mandibles moving laterally during feeding _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 23

 

The head is not well developed, but if partially developed the mandibles move vertically, parallel to each other or at an angle

inward. Or if the head is not visible and the anterior end is pointed and has mouth hooks or reduced parts

(Fig. 13, Fig. 14, Fig. 15). Or the larva resembles a grub rounded at both ends (Fig. 16). Or, the larva has an elongated

siphon at the end of the abdomen (Fig. 17) _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 28

 

23. Larvae are aquatic or semiaquatic, living only in swift streams or in tree holes, mud, pond shores or in open water _ _ 24

 

24. There are prolegs on all body segments _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 25

 

Prolegs occur only on some body segments (Fig. 18) _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _27

 

25. The head is distinct. The thorax and abdominal segments are divided into annuli or rings, usually each ring having a dorsal

plate. Respiratory openings occur on the prothorax and anal segments (amphipneustic) _ _ _ _ _ _ _ _ _ _ _ _ Psychodinae

 

The head is also distinct, but segments of the thorax and abdomen do not have divisions and otherwise differ from the previous

description _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 26

 

26. Thoracic segments are fused to form an enlarged portion that is thicker than the abdomen (fig. 105). Respiration is by

spiracles located at the end of an elongated tube or siphon, or the posterior spiracles are flattened (metapneustic)

(mosquitoes) _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Culicidae

 

The segments of the thorax and abdomen are almost equal in diameter. All thoracic segments are much enlarged. Larvae

resemble snakes (Fig. 19) with smooth bodies (Culicoides, Bezzia, etc.) _ _ _ _ _ Heleidae & Ceratopogonidae

 

27. Two prolegs occur on each segments #1 & #2 of the abdomen. Tracheae extend in a pair of discs on abdominal segment #8

_ _ _ _ larvae at water surface are U-shaped _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Dixidae

 

27b. Prolegs occur only on the prothoracic segment. The larva's posterior end has an adhesive disc for attachment. Larvae

occur in swift water (black flies) _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Simuliidae

 

27 c. Prolegs are present on the prothorax and posterior end of the larva or they may be reduced (gnats) _ _ _ _ _ _ _ _ _ _

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Tendipedidae & Chironomidae

 

27 d. Larvae have a well-developed head with stout bristly hairs or spines (Fig. 20). The body also has similar hairs. The

tip of the abdomen has two groups of long hairs. The abdomen also has prologs (sand flies) _ _ _ _ Phlebotominae

 

28. Larvae are cylindrical and pointed at both ends. Mandibles are hook like and move vertically and parallel to each other.

Spiracles are located in a vertical cleft and usually on the tip of a posterior siphon (Fig. 14) _ _ _ _ _ _ _ _ _ _ Tabanidae

 

Larvae are different from previous description _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 29

 

29. Larvae are aquatic and appear stout and grub like with a long telescopic terminal siphon (rat-tailed maggots (Fig. 17) _ _ _ _

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _(partly) Serphidae (= Proctotrupidae)

 

Larvae do not fit the previous descriptions (See Key on Myiasis-causing Flies)

 

 

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

 

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

 

Aldrich, J. M. 1905. A catalogue of North American Diptera. Smithsonian Misc. Coll. 46.

Aldrich, J. M. 1915. The dipterous genus Symphoromyia in North America. Proc. U.S. Nat. Mus.49: 113-42.

Borror, D. J., D. M. DeLong & C. A. Triplehorn. 1981. An Introduction To The Study of Insects. 5th ed. Saunders College Publ. 827 p.

Brown, B.V. 2001. Flies, gnats, and mosquitoes.. In Encyclopedia of Biodiversity, Volume 2. Academic Press. pp. 815-826

Cameron, A. E. 1922. The morphology and biology of a cattle-infesting black fly (Simulium simile Mall.). Dept. Agr. Dom. of Canada, Bull 5.

Cameron, A. E. 1926. Bionomics of the Tabanidae (Diptera) of the Canadian prairies. Bull. Ent. Res. 17: 1-42.

Curran, C. H. 1934. The families and genera of North American Diptera. New York Publ.

Disney, R. H. L. 1999. British Dixidae (meniscus midges) & Thaumaleidae (trickle midges): keys with ecological notes. Freshwater

Biological Association 56. 128 pp.

Dove, W. E. & D. G. Hall. 1934. Dikes and automatic tide gates in control of sandflies and salt marsh mosquitoes. J. Parasitol. 20: 337-38.

Johannsen, O. A. 1934. Aquatic Diptera. I. Cornell Univ. Agr. Exp. Sta., Mem. 164: 56-64.

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

Oldroyd, H. 1964. The natural history of flies. Weidenfeld and Nicolson, London. 324 pp.

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.

Ross, H. H. 1940. The Rocky Mountain "black fly," Symphoromyia atripes. Ann. Ent. Soc. Amer. 33: 254-57.

Skevington, J.H. & P. T. Dang, eds. 2002. Exploring the diversity of flies (Diptera). Biodiversity 3(4): 3-27.

Walton, W. R. 1909. An illustrated glossary of chaetotaxy and anatomical terms used in describing Diptera. Ent. News 20: 307-19.

Williston, S. W. 1908. Manual of North American Diptera. New Haven, Conn.