Ana səhifə

Key to the Orders of Aquatic Hexapoda (Insects and Collembola) of Michigan

Yüklə 66.13 Kb.
ölçüsü66.13 Kb.

Key to the Orders of Aquatic Hexapoda (Insects and Collembola) of Michigan

1a. Thorax without segmented legs (except pupae) 2

1b. Thorax with 3 pairs of segmented legs 3
2a (1a). Mummy-like, in a case, often silk-cemented and containing vegetable or mineral matter

pupae (not keyed)

2b. Not in a case; mobile larvae, mostly with prolegs or pseudopods on one or more segments

3a (1b). With large, functional wings 4

3b. Wingless, or with developing wings (wingpads) or brachypterous wings 5

4a (3a). All wings completely membranous, with numerous veins non-aquatic adults

4b. Mesothoracic wings hard, shell-like, meeting along middorsal line; chewing mouthparts

Coleoptera adults

4c. Mesothoracic wings hardened in basal half only, overlapping along middorsal line (except in Pleidae); sucking mouthparts, formed into a broad or narrow tube Heteroptera adults (in part)

5a (3b) Thoracic legs 4-segmented; abdomen with  6 segments; abdomen with furcula


5b. Thoracic legs 5-segmented; abdomen with  6 segments; abdominal furcula absent 6

6a (5b). With 2 or 3 long, thin, terminal and multi-segmented filaments 7

6b. Terminal filaments absent, or consisting of < 10 segments 8

7a (6a). Tarsal claws single; middle abdominal segments with variously-shaped (platelike, featherlike, or leaflike) gills; usually with three terminal filaments Ephemeroptera

7b. Tarsal claws double; middle abdominal segments without gills; two terminal filaments

8a (6b). Labium modified into a large, elbowed, extensile grasping organ Odonata

8b. Labium not modified as above, with chewing or sucking mouthparts 9

9a (8b). Sucking mouthparts, formed into a narrow tube 10

9b. Chewing mouthparts, not formed into a narrow tube 11

10a (9a). Parasitic on sponges; all tarsi with 1 claw Neuroptera, Sisyridae

10b. Free-living; mesotarsi with 2 claws Heteroptera adults and larvae

11a (9b). Ventral abdominal prolegs each with a ring of fine hooks (crochets)

Lepidoptera, Pyralidae

11b. Abdomen without ventral prolegs, except on terminal segment 12

12a (11b). Antennae extremely small, inconspicuous and 1-segmented Trichoptera

12b. Antennae elongate, with three or more segments 13

13a (12b). Without long lateral filaments Coleoptera larvae (in part)

13b. With long lateral filaments 14

14a (13b)..A single claw on each tarsus, or with two claws and abdomen terminating in 2 slender filaments or a median proleg with 4 hooks Coleoptera larvae

14b. Each tarsus with 2 claws, and abdomen terminating in a single slender filament or abdomen terminating with 2 prolegs, each with 2 hooks Megaloptera larvae

Some Useful Order-Level Characteristics of the Aquatic Hexapoda

Wing Life Jointed Abdomen No.

Folding Cycle Order Legs? Scleratized? Instars
Apterous Ametabolous Collembola Y Y ?
Paleoptera Hemimetabolous Ephemeroptera Y Y 20-30

Odonata Y Y 10-20

Neoptera Plecoptera Y Y 20-25

Heteroptera Y Y 10-20

Holometabolous Megaloptera Y N 5

Neuroptera Y N 3

Trichoptera Y N 4-5

Lepidoptera usually N 5-6

Coleoptera Y sometimes 5

Diptera N N 4

Key to the Michigan Families of Adult Collembola - Springtails

1a. Body somewhat globular; thorax and abdomen indistinctly segmented Smithuridae

1b. Body elongate; thorax and abdomen distinctly segmented 2
2a (1b). Mouthparts directly downward; furcula present, and forks distinctly converge

Poduridae, Podura aquatica

2b. Mouthparts directed forward; furcula absent or forks do not distinctly converge


Key to the Michigan Families of Larval Ephemeroptera - Mayflies

1a. Mandibles with large forward-projecting tusks; all gills on abdominal segments 2-7 with fringed margins, projecting dorsally or laterally 2

1b. Mandibles without tusks; fringed gills absent or projecting ventrolaterally 4
2a (1a). Gills lateral, projecting from sides of abdomen; foretibiae slender, sub-cylindrical


2b. Gills dorsal, curving up over abdomen; foretibiae fossorial, expanded in width 3

3a (2b). Apex of metatibia rounded; mandibular tusks curved inward and downward apically, with at least one tubercle on inner margin near apex, or with many tubercles on upper surface


3b. Apex of metatibia projected into an acute point ventrally; mandible tusks curved upward or outward apically Ephemeridae

4a (1b). Mesonotum modified into a carapace-like structure that covers the gills on abdominal segments 1-6 Baetiscidae

4b. Mesonotum not modified into a carapace; gills exposed 5

5a (4b). Head and pronotum with pads of long, dark setae on each side; fringed gills projecting ventrolaterally; very rare, unlikely to be encountered except in large sandy rivers in western Michigan Behningiidae

5b. Head and pronotum without pads of long, dark setae; without ventrolateral fringed gills 6

6a (5b). Gills absent from abdominal segment 2, sometimes from 1 and 3 also; gills on segment 3 and 4 may be operculate, covering other gills Ephemerellidae

6b. Gills present on abdominal segments 1-7 or 2-7 7

7a (6b). Gills on abdominal segment 2 operculate or semi-operculate, covering or partially covering gills on succeeding abdominal segments 8

7b. Gills on abdominal segment 2 similar to other gills 9

8a (7a). Operculate gills on abdominal segment 2 sub-triangular, well separated mesally; succeeding gills without fringed margins Leptohyphidae

8b. Operculate gills on abdominal segment 2 sub-quadrate and overlapping mesally; succeeding gills with fringed margins Caenidae

9a (7b). Head flattened dorsa-ventrally; eyes and antennae dorsal; gills a single lamella, often with a fibrilliform tuft 10

9b. Head not flattened; antennae and eyes lateral; gills not as above 11

10a (9a). Gills with finger-like projection on lamellae; tarsal claws very long Pseudironidae

10b. Gills without such a finger-like projection; tarsal claws normal Heptageniidae

11a (9b). Claws on protarsus much shorter than long, slender claws of meso- and metatarsi 12

11b. Claws on all tarsi similar in length and structure 13

12a (11a). Protarsal claw simple, with long, slender denticles; spinose pad present on procoxa


12b. Protarsal claw bifid; no spinose pad on procoxa Metretopodidae

13a (11b). Prothoracic leg with dense row of setae along inner surface 14

13b. Prothoracic leg without dense row of setae along inner surface 15

14a (13a). Gills single lamellae with fibrilliform tuft underneath of gill plate; gill tuft at base of procoxa Isonychiidae

14b. Gills on abdominal segments 2-7 small, lateral, lanceolate, with posterior fringe; gill on segment 1 large, fibrilliform, projecting between metacoxae Oligoneuriidae

15a (13b). Gills forked, or bilamellate and terminating in a filament or point Leptophlebiidae

15b. Gills formed as single or double lamellae, sometimes with ventral fibrilliform tuft 16

16a (15b). Abdominal segments 8 and 9 produced posterolaterally into distinct, flattened spines; if spines are weak, antennal length < 2x width of head 17

16b. Abdominal segments 8 and 9 without such spines; if weak spines are present, antennal > 2x width of head Baetidae

17a (16a). Head, pronotum, and mesonotum with conspicuous lateral spines; a row of median spines on abdominal terga; very rare, only in large rivers with shifting sand substrates


17b. Without such spines 18

18a (17b). Gills single, with sclerotized band on ventral margin and little or no tracheation; maxilla with crown of pectinate spines Ameletidae

18b. Gills with well-developed tracheation; maxilla without pectinate spines Siphlonuridae

Key to the Michigan Families of Larval Odonata – Dragon- and Damselflies

1a. Body slender, head wider than thorax and abdomen ; abdomen ending with three caudal lamellae (gills are fragile, often falling off with rough or frequent handling of live or preserved specimens) Zygoptera, 2

1b. Body stout, head usually narrower than thorax and abdomen ; no large caudal lamellae, rather body ending in 3 stiff, pointed valves, separated by pointed cerci Anisoptera, 4
2a (1a). Antennal segment 1 elongate, as long or longer than remaining segments ; prementum with prominent cleft Calopterygidae

2b. Antennal segment 1 short, distinctly less than length of remaining segments 3

3a (2b). Labium long, in folded position reaching back to, or beyond, middle coxae, in basal half markedly narrowed Lesitdae

3b. Labium shorter, in folded position never reaching the middle coxae, not markedly narrowed in basal half Coenagrionidae

4a (1b). Mentum flat, Michigan species without premental and palpal setae 5

4b. Mentum spoon-shaped, usually with premental and always with palpal setae 7

5a (4a). Antennae 4-segmented, third segment often elongate ; fore and middle tarsi 2-segmented ; ligula without a median cleft Gomphidae

5b. Antennae 6- and 7-segmented ; fore and middle tarsi 3-segmented ; ligula with a median cleft 6

6a.(5b). Antennae segments short, thick, and hairy ; prementum with sides sub-parallel in distal three-fifths, abruptly narrowed near base ; a pair of lateral-dorsal abdominal hair tuft present ; only in forested seeps in extreme southwestern Michigan Petaluridae
6b. Antennal segments slender and bristle-like ; prementum widest in distal half, then much narrower in basal half or more ; abdomen without lateral-dorsal abdominal hair tufts

7a.(4b). Distal edge of lateral lobe with large, irregular teeth without associated setae, ligula with a median tooth-like cleft Cordulegastridae
7b. Distal edge of lateral lobe entire, or with even-sized dentations, with associated setae ; ligula not as above 8
8a.(7b). Head with thick, erect frontal horn positioned between antennae ; metafemur very long, reaching at least to apex of abdominal segment 8 ; metasternum with broad, median tubercle


8b. Head without frontal horn positioned between antennae ; metafemur not reaching apex of abdominal segment 8 ; metasternum without median tubercle 9

9a(8b). Distal edge of lateral lobe of labium with prominent crenations, usually at least as one-fourth deep as wide ; cerci usually at least one-half as long as epiproct ; abdomen generally ends abruptly 10

9b. Distal edge of lateral lobe of labium generally with crenations less than one-fourth as wide, or obsolete ; cerci usually less than one-half as long as epiproct ; abdomen distally more tapered Libellulidae (in part)

10a (9a). Lateral spine of abdominal segment 8, when present, shorter than middorsal length of abdominal segment 9 Corduliidae

10b. Lateral spine of abdominal segment 8 as long as middorsal length of abdominal segment 9, or longer Libellulidae, genus Pantala

Key to the Michigan Families of Larval Plecoptera – Stoneflies

1a. Labial glossa and paraglossa subequal 2

1b. Labial paraglossa produced much further than the glossa 6
2a (1a). Large tufted gills on the sides of abdominal segments 1 and 2 Pteronarcyidae

2b. No such gills 3

3a (2b). Thorax robust, wider than abdomen; developing wing pads divergent 4

3b. Thorax and abdomen about equal in length; wing pads roughly parallel 5

4a (3a). Tarsomere 2 subequal or greater than 1 Taeniopterygidae

4b. Tarsomere 2 much shorter than 1 Nemouridae

5a (3b). Mesothoracic wing pads similar in shape, 2-3x farther apart than metathoracic pads ; abdominal segments 7-9 a complete sclerotized ring, not divided by a ventrolateral fold


5b. Mesothoracic wing pads subequally separated or absent, or metathoracic wing pad truncated ; terga and sterna of abdominal segments 1-9 divided by a membranous fold ventrolaterally Capniidae

6a (1b). Finely branched gills present on all thoracic sterna Perlidae

6b. Finely branched gills, if present, only on first thoracic sterna 7

7a (6b). Margins of metathoracic wing pads divergent; cerci roughly the length of abdomen; apical segment of labial palp basally about as wide as preceding segment Perlodidae

7b. Margins of metathoracic wing pads nearly parallel ; cerci about 0.75x the length of abdomen ; apical segment of labial palp basally much thinner as preceding segment (rare in MI)


Key to the Michigan Families of Larval Trichoptera – Caddisflies

1a. Larval case of sand grains resembling a snail case ; anal claw with comb of teeth, not hook-shaped Helicopsychidae

1c. Larval case and anal claw not as above 2
2a (1b). All three thoracic segments with dorsal sclerotized plates 3

2b. Metanotum, and sometimes the mesonotum, entirely membranous or largely so but with several pairs of smaller sclerites 4

3a (2a). Abdomen with ventrolateral branched gills ; anal proleg projecting freely from abdomen, with brush-like setae and large anal claw ; posterior margin of meso- and metanotal plates lobate Hydropsychidae

3b. Abdomen lacking ventrolateral gills ; anal proleg usually not projecting freely from abdomen, claw always small and without setal brush ; small (<6 mm), construct purse- or barrel-shaped portable cases, or silken domes fastened to rocks Hydroptilidae

4a (2b). Antennae long and prominent, at least 6x as long as wide, and/or sclerotized plates on mesonotum lightly pigmented except for pair of dark curved lines on posterior half


4b. Antennae of normal length, < 3x as long as wide and usually no more than an inconspicuous stub ; mesonotum never with pair of dark curved lines as above 5

5a (4b). Mesonotum usually lacking sclerotized plates , or with only small sclerites covering not more than half of notum ; pronotum never with anterolateral lobe 6

5b. Mesonotum largely covered by sclerotized plates, variously subdivided and usually pigmented; pronotum sometimes with prominent anterolateral lobe 11

6a (5a). Abdominal segment 9 with dorsal sclerotized plate 7

6b. Abdominal segment 9 without dorsal sclerotized plate 8

7a (6a). Larvae construct tubular portable case, usually of plant material ; prosternal horn present Phryganeidae

7b. Larvae construct tortoise-like portable case of rock fragments ; without prosternal horn; basal half of anal proleg broadly joined to abdominal segment 9, anal claw with at least one dorsal accessory hook Glossosomatidae

7c. Larvae free-living without portable cases but construct fixed pupal enclosures; without prosternal horn; most of anal proleg free from abdominal segment 9, anal claw without dorsal accessory hook, although secondary lateral claw may be present Rhyacophilidae
8a (6b). Labrum membranous and T-shaped , often withdrawn from view in preserved specimens; larvae construct fixed sack-like nets of silk Philopotamidae

8b. Labrum sclerotized, rounded and articulated in normal way 9

9a (8b). Trochantin of prothoracic leg broad and hatchet-shaped, separated from episternum by dark suture line ; larvae construct fixed tubular retreats on rocks and logs Psychomyiidae

9b. Trochantin of prothoracic leg with apex acute, fused completely with episternum without separating suture ; 10

10a (9b). Tarsi of all legs strongly flattened, tibiae shorter than tarsi ; larvae burrow into sandy deposits and construct tubes of sand grains Dipseudopsidae

10b. Tarsi of all legs normal, not flattened, tibiae longer than tarsi ; larvae construct exposed funnel-shaped capture nets or flattened retreats Polycentropodidae

11a (5b). Abdominal segment 1 lacking both dorsal and lateral humps , each metanotal sa1 lacking entirely or represented only by single setae without sclerite Brachycentridae

11b. Abdominal segment 1 always with lateral hump on each side, though not always prominent, and usually with dorsal hump ; metanotal sa1 always present, usually with prominent sclerite with at least one setae 12

12a (11b). Mesopleuron extended as an acute process ; cases of rock fragments Goeridae

12b. Mesopleuron not extended as an acute process 13

13a (12b). Antennae situated close to anterior margin of eye ; no dorsal hump on abdominal segment 1 Lepidostomatidae

13b. Antennae not situated close to anterior margin of eye, ; dorsal hump on abdominal segment 1 almost always present 14

14a (13b). Antennae situated approximately midway between anterior margin of head capsule and eye ; prosternal horn usually present although sometimes short ; chloride epithelia usually present on some abdominal segments 15

14b. Antennae situated close to or at anterior margin of head capsule ; prosternal horn and chloride epithelia never present 17

15a (14a). Mesonotal plates with anteromedian emargination Uenoidae

15b. Mesonotal plates without such emargination 16

16a (15b). Mandibles usually with uniform scraper blades , or if mandibles toothed , metanotal sa1 with 25 or more setae on membrane between sclerites Apataniidae

16b. Mandibles almost always toothed ; metanotal sa1 lacking setae on membrane between sclerites, or fewer than 25 setae if present Limnephilidae

17a (14b). Tarsal claw of hind leg modified to form short setose stub ; cases flat oval of sand with lateral flanges Molannidae

17b. Tarsal claws of hind leg not different in structure from those of other legs 18

18a (17b). Fore trochantin relatively large, apex hook-shaped ; dorsum of anal proleg with cluster of approximately 30 or more setae posteromesad of reduced lateral sclerite


18b. Fore trochantin smaller, apex not hook-shaped ; dorsum of anal proleg with no more than 3-5 setae posteromesad of lateral sclerite, sometimes with short spines Odontoceridae

Key to the Michigan Families of Larval Megaloptera – Dobson- and Alderflies

1a. With 7 pairs of lateral segmented abdominal appendages; a long terminal anal filament; anal prolegs absent; larvae rarely exceed 25 mm in length Sialidae

1b. With 8 pairs of lateral abdominal appendages that are not or imperfectly segmented; no terminal anal filament; anal prolegs present; mature larvae large, exceeding 30 mm


Key to the Michigan Families of Adult Heteroptera – Aquatic and Semi-aquatic Bugs

Note: Lengths refer to adults, with have developed wings.

1a. Antennae shorter than head, concealed in groove beneath eye; aquatic 2

1b. Antennae as long, or longer, than head, usually plainly visible; semiaquatic 8

2a (1a). Rostrum broad, blunt, triangular, and indistinctly segmented; front tarsus broad, formed into a one-segmented scoop Corixidae

2b. Rostrum cylindrical or cone-shaped, distinctly 3- or 4-segmented; front tarsus not scoop-like

3a (2b). End of abdomen with a long, slender, rounded respiratory appendage Nepidae

3b. Apical respiratory appendages, if present, short and flat 4

4a (3b). Eyes protuberant; ocelli present; metathoracic leg without natatory setae; 7-9 mm, toad-like in appearance; riparian Gelastocoridae

4b. Eyes not protuberant; ocelli absent; metathoracic leg with natatory setae; not toad-like in appearance 5

5a (4b). Very large,  18 mm in length; short, flat, retractile apical abdominal appendages present Belastomatidae

5b. Smaller, < 16 mm in length; apical abdominal appendages absent 6

6a (5b). Profemur almost as wide as long; body flattened; 10-12 mm long Naucoridae

6b. Profemur elongate; body elongate or hemispherical; backswimmers 7

7a (6b). Body shape hemispherical; small, 2.0-2.5 mm long Pleidae

7b. Body elongate; larger, > 5 mm long Notonectidae

8a (1b). Claws of at least protarsi inserted before apex 9

8b. Claws of all tasi at apex 10

9a (8a). Metafemur very long, greatly surpassing apex of abdomen Gerridae

9b. Metafemur shorter, not, or only slightly surpassing apex of abdomen Veliidae

10a (8b). Head as long as entire thorax; very slender; eyes set about halfway to base; 7.5 – 10.0 mm long Hydrometridae

10b. Head short and stout, eyes near posterior margin 11

11a (10b). Winged, with veins in membrane of hemelytra; riparian Saldidae

11b. Wingless, or if winged, without veins in the membrane 12

12a (11b). Tarsi 3-segmented; head without deep longitudinal ventral groove to receive rostrum; rostrum completely visible from lateral view; legs with scattered, stiff, black bristles; body length 2.5-4.0 mm long Mesoveliidae

12b. Tarsi 2-segmented; head with deep longitudinal ventral groove to receive rostrum; rostrum only partially visible from lateral view; legs without bristles; smaller, body length < 2.0 mm


Key to the Michigan Families of Coleoptera – Beetles

1a. Wingless Larvae, 2

1b. With well-developed, functional wings Adults, 12
2a (1a). Each tarsus with 2 claws 3

2b. Each tarsus with 1 claw 5

3a (2a). Abdomen with 10 pairs of lateral filaments; 4 conspicuous hooks on last abdominal segment Gyrinidae

3b. Abdomen without lateral filaments or with only 6 pairs; without conspicuous hooks on last abdominal segment 4

4a (3b). Urogomphi usually longer than last abdominal segment, but if shorter then legs elongate with natatory setae; posterior half of abdomen conspicuously narrowed; mandibles elongate, pointed for piercing Dytiscidae

4b. Urogomphi shorter than last abdominal segment; posterior half of abdomen little narrowed; legs stout, short and without natatory setae; mandibles short, adapted for chewing Noteridae

5a (2b). Legs distinctly 5-segmented; abdomen terminating in 1 or 2 long filaments Haliplidae

5b. Legs appearing 4-segmented; abdomen not terminating in long filaments 6

6a (5b). Mandibles large, readily visible from above Hydrophilidae

6b. Mandibles not readily visible from above 7

7a (6b). Antenna long, filiform, as long as head and thorax combined Scirtidae

7b. Antenna much shorter than head and thorax combined 8

8a (7b). Body oval, extremely flat; head completely concealed from dorsal view Psephenidae

8b. Body elongate, round, or triangular in cross-section; head exposed 9

9a (8b). Each thoracic and abdominal segment covered by a flat, plate-like sclerite dorsally; last abdominal segment with clump of large papillae ventrally Lampyridae

9b. Thoracic and abdominal segments rounded dorsally; without clump of large papillae ventrally

10a (9b). All terga rounded and pale; grub-like larva with two spines on last abdominal segment


10b. Body elongate and sclerotized, with ventral movable operculum closing caudal chamber containing gills 11

11a (10b). Last abdominal tergum apically notched; a group of 5 stemmata posterior to base of antenna Elmidae

11b. Last abdominal tergum broadly rounded; one ventral stemma below base of antenna in addition to 5 stemmata posterior to base Lutrochidae

12a (1b). Head formed into a snout or beak anteriorly; antenna geniculate Curculionidae

12b. Head not formed into a beak or snout; antennae not geniculate 13

13a (12b). Two pairs of eyes, a dorsal and ventral pair divided by sides of head; meso- and metathoracic legs extremely flattened; tarsi folded fan-wise; shiny black beetles Gyrinidae

13b. One pair of eyes; meso- and metathoracic legs not extremely flattened; tarsi not folded fan-wise 14

14a (13b). Metacoxae expanded into large plates that cover 2-3 abdominal sterna and bases of metafemora Haliplidae

14b. Metacoxae not expanded into large plates 15

15a (14b). Prosternum with a postcoxal process extending posteriorly to mesocoxae; first visible abdominal sternite completely divided by metacoxal processes 16

15b. Prosternum with postcoxal process absent or short; first visible abdominal sternite extending for its entire breadth behind coxal processes 17

16a (15a). Enlarged median metasternal keel present; protibia with large, curved spur at apex; scutellum concealed Noteridae

16b. Enlarged median metasternal keel absent; without large, curved spur at apex; scutellum concealed or exposed Dytiscidae

17a (15b). Antenna short, club-shaped, with segment 4, 5, or 6 modified to form a cupule; maxillary palp usually longer than antenna 18

17b. Antenna filiform or pectinate, usually longer than maxillary palp 19

18a (17a). Antenna with 5 segments past cupule Hydraenidae

18b. Antenna with 3 segments past cupule Hydrophilidae

19a (17b). Antenna slender, filiform Elmidae

19b. Antenna short with pectinate club Dryopidae

Key to the Michigan Families of Larval Diptera – True Flies

1a. Mandibles moving against one another in a horizontal or oblique plane; head capsule usually completely sclerotized and fully visible, but retracted and partially sclerotized in Tipulidae

Suborder Nematocera, 2

1b. Mandibles or mouth hooks moving parallel to one another in a vertical plane

Suborder Brachycera, 13
2a (1a). Head capsule incompletely sclerotized, with longitudinal incisions of varying depths dorsolaterally, in extreme cases head reduced to several slender rods, and more or less retracted into thorax Tipulidae

2b. Head capsule complete, without longitudinal incisions and incapable of retraction within thorax 3

3a (2b). Body without distinct constriction between head and thorax; body appearing 7-segmented, segments 1-6 each with a prominent ventral suctorial disk Blephariceridae

3b. Body with distinct constriction between head and thorax; body not appearing as above, and without ventral suctorial disks 4

4a (3b). Abdomen terminating in a long, slender, retractile respiratory tube; abdominal and thoracic segments with multiple transverse ridges or rows of small setae or setiferous papillae; 1st 3 abdominal segments with a pair of ventral prolegs, sometimes very small, bearing a single, slender, curved claw Ptychopteridae

4b. Without having any of the above characteristics 5

5a (4b). Thorax with segments fused, indistinctly differentiated, forming a single segment that is wider than the abdomen; thoracic and abdominal segments with prominent lateral fanlike tufts of long setae, and/or terminal segment with an anal setal fan 6

5b. Thorax segments usually distinct, thorax and abdomen about equal in diameter, or abdomen wider (except Dixidae); setae on thoracic and abdominal segments not tufted, and anal fan of terminal segment absent 7

6a (5a). Paired crochet-bearing prolegs ventrally on abdominal segments 1 and usually 2; abdomen with 2 flattened dorsolateral post-spiracular lobes having setose margins projecting above a conical, dorsally sclerotized segment bearing the terminal anus and anal papillae


6b. Abdominal segments without prolegs; abdomen not as above 7

7a (6b). Prothorax with 1 or a pair of prolegs ventrally 8

7b. Prothorax without prolegs 11

8a (7a). Head capsule usually with a pair of conspicuous, folding, labral dorsolateral fans; posterior of abdomen swollen, with terminal ring or circlet of numerous radiating rows of minute hooks Simuliidae

8b. Head capsule without labral fans; posterior of abdomen not swollen, posterior of abdomen not as above, although anal proleg(s) bearing crochets may be present 9

9a (8b). Spiracles on both ends of body, prothoracic spiracles on short stalks, and posterior spiracles opening into a transverse cleft between fingerlike processes on abdominal segment 8; prothoracic and anal prolegs unpaired; riparian Thaumaleidae

9b. Without spiracles; prothoracic or anal prolegs usually paired, although a slight separation of apical spines may be present 10

10a (9b). All body segments with prominent dorsal tubercles and/or setae

Ceratopogonidae (in part)

10b. All body segments lacking prominent dorsal tubercles and setae Chironomidae

11a (7b). Posterior 2 abdominal segments with long filamentous processes, pairs of such processes arising laterally on the penultimate segment, dorsolaterally on the terminal segment, and from near the apex of 2 elongate cylindrical prolegs that project postero-ventrally from the terminal segment Tanyderidae

11b. Posterior 2 abdominal segments without long filamentous processes; at most, only a single anal proleg present 12

12a (11b). All body segments secondarily divided into 2 or 3 subdivisions, with some or all of these subdivisions bearing dorsal sclerotized plates, remainder of integument with numerous dark spots, which, together with the dorsal plates, impart a gray-brown coloration; spiracles on both ends of body, posterior spiracles at apex of a relatively short, conical respiratory tube


12b. Body segments usually not secondarily divided; integument smooth, shiny, and creamy white, lacking all surface features except a few setae, and sometimes a retractile anal proleg bearing a few crochets; without respiratory tubes Ceratopogonidae (in part)

13a (1b). Sclerotized portions of head capsule exposed externally, although sometimes greatly reduced, in which case slender tentorial and metacephalic rods prominent internally

Infraorder Orthorrhapha, 14

13b. External sclerotized portions of head capsule absent; head reduced to an internal cephalopharyngeal skeleton Infraorder Cyclorrhapha, 18
14a (13a). Head mostly visible, truncate in shape; body dorsoventrally flattened; margin of posterior spiracular chamber usually with long, soft setae Stratiomyidae

14b. Head vestigial or mostly retracted into thorax and elongate; body nearly circular in cross-section; spiracular chamber without long, soft setae 15

15a (14b). Body cylindrical; first 7 abdominal segments girdled by fleshy swellings with 3-4 pairs of prolegs that may bear hooks; terminal segments of abdomen tapered or rounded, with spiracles present, but never with terminal lobes or appendages Tabanidae

15b. Body variable; abdomen with at most 1 pair of prolegs per segment, or with creeping welts; spiracles present or absent; terminal abdominal segment with 1-2 pairs of appendages or lobes 16

16a (15b). End of abdomen with a pair of divergent, ciliated process, longer than prolegs; spiracles absent Athericidae

16b. End of abdomen variable, but not ciliated as above, usually shorter than prolegs and reduced to fleshy lobes; abdominal segments with creeping welts or with prolegs lacking from first abdominal segment; spiracles absent or present 17

17a (16b). End of abdomen with spiracles surrounded by 4 smooth pointed lobes on last abdominal segment, with posterior spiracles situated at the base of the upper 2 lobes; metacephalic rods expanded posteriorly in dorsal view Dolichopodidae

17b. Usually without spiracles, with last abdominal segment with 1-4 rounded lobes bearing apical setae, and abdominal segments bearing paired prolegs with apical crochets; if with spiracles at end of abdomen, then posterior segment with only a single lobe below spiracles, and abdominal segments with ventral creeping welts; metacephalic rods slender posteriorly in dorsal view Empididae

18a (13b). Pharyngeal skeleton with the “hypopharynx” produced as a median tooth; rare, predator on psychodid larvae in pitcher plants and waste-treatment plants Phoridae

18b. Pharyngeal skeleton not so produced; rarely associated with pitcher plants 19

19a (18b). Posterior spiracular plates fused or very closely approximated, usually on apex of a retractile respiratory tube, often at least half as long as body Syrphidae

19b. Posterior spiracular plates always distinctly separated, whether mounted on a retractile respiratory tube or not 20

20a (19b). Caudal spiracular disc with palmate hairs surrounded by 8-10 lobes, some of which may be very short; body wrinkled Sciomyzidae

20b. Caudal spiracular disk without palmate hairs; if surrounded by lobes, body not wrinkled

21a (20b). Posterior abdominal segment somewhat tapered, sometimes ending in a retractile respiratory tube; integument of posterior abdominal segments covered with setae or spinules, or with hair-like tubercles on some segments; posterior prolegs absent or shorter than respiratory tubes Ephydridae

22b. Posterior abdominal segment rather truncate and/or integument with setae only on intersegmental areas; tubercles, if present, restricted to posterior abdominal segment; posterior prolegs as long as, or longer, than respiratory tube Muscidae

Verilənlər bazası müəlliflik hüququ ilə müdafiə olunur © 2016
rəhbərliyinə müraciət