Entomology 3

Question 1

Anopheles Mosquito

Answer 1

Medium sized dipteran fly with long proboscis and scales on the wing veins. Female attenae sparsely haired and palps approximately as long as proboscis. Male antennae plumose and clubbed palps approximately as long as proboscis.

Question 2

Culex Mosquito

Answer 2

Medium sized dipteran fly with long proboscis. Female antennae sparsely haired and palps are much shorter than proboscis. Male antennae plumose and feathered, palps longer than proboscis and tapered to a point. Body of mosquito typically dull brown in appearance without conspicuous markings. Scales on the wing veins uniformly brown in most species. Tip of the abdomen is blunt.

Question 3

Aedes Mosquito

Answer 3

Medium sized dipteran fly with long proboscis. Female antennae sparsely haired and palps are much shorter than proboscis. Male antennae plumose and feathered palps are tapered and longer than proboscis. Body of mosquito typically black/brown with conspicuous patterns of silver/white scales on dorsal thorax. Silver/white bands on abdomen and legs. Wing vein scales uniformly black or brown. Tip of the abdomen is pointed.

Question 4

Aedes aegypti Mosquito

Answer 4

Silver lyre pattern on thorax. White banding on the legs and abdomen

Question 5

Aedes albopictus Mosquito

Answer 5

Silver line on median thorax. White banding on the legs and abdomen

Question 6

Mansonia Mosquito

Answer 6

Medium sized, black/brown dipteran fly with long proboscis. Female antennae sparsely haired and palps are much shorter than proboscis. Mosquitoes have a mottled arrangement of light and dark scales on legs/body/wings. Legs typically have pale bands. Wings bear large asymmetrical scales.

Question 7

Haemagogus Mosquito

Answer 7

Medium sized dipteran fly, with long proboscis. Metallic green and blue scales cover the body and head. Male antennae plumose and palps are much shorter than proboscis. Female antennae sparsely haired and palps are much shorter than proboscis. Antepronotal lobes are enlarged

Question 8

Phlebotamine Sandfly

Answer 8

Small, very hairy. Wings are also hairy and are held in a V shape when at rest. Mouth parts at least as long as head. Palps long, with 5 segments and droop downwards. Wing veins appear to run parallel. Second vein branches twice. Pointed wing - lanceolate. (Pill box or slide)

Question 9

Simulium Blackfly

Answer 9

Small dark bodied fly with humped back. Wings are colourless, short and broad with very fine veins. Antennae are short, simple and cigar shaped. Female eyes are dichoptic (eyes are separated above the antennae) and have small ommatidia (individual units of the eye). Male eyes are holoptic (joined above the antenna) and have large and small omatidia.

Question 10

Culicoides Biting midges

Answer 10

Small bodied, hunched fly. Wings are mottled, with a characteristic fork. Mouth parts and palps are inconspicuous and sexes can be determined by the antenna, plumose in males and sparsely haired in females.

Question 11

Chrysops Deerfly

Answer 11

Large bodied fly, with one or more transverse bands cross wing and a characteristic hexagonal discal cell. In life the eyes are iridescent and commonly have spots of red, green or purple colour. The females are dichoptic (eyes are separated above the antenna), while the males are holoptic (joined above the antenna). 3rd segment of antenna is split into 4 subdivisions distally.

Question 12

Glossina Tsetse fly

Answer 12

Large, narrow-bodied fly, grey, brown or yellowish in colour. Rigid forward-projecting proboscis is characteristic, as are the branched hairs on the arista and the hatchet cell of wing.

Question 13

Flea Egg

Answer 13

Very small, oval, pearly white or yellowish, smooth egg with no operculum. (Pill box)

Question 14

Triatoma Triatomine bug

Answer 14

Large insect with a cone shaped head, prominent dark eyes and a distinct neck. The antenna extend from the head laterally and have four segments. The proboscis is thin and straight and lies to the ventral side of the head when at rest. Rhodnius antenna extends from the end of the head. Triatoma antenna extends from the middle of the head. Panstrongylus antenna extends from the eyes.

Question 15

Cimex Bed bug

Answer 15

Small, oval, dorsoventrally flattened insect. Yellowish to dark brown or red in colour, with the proboscis folded under the head at rest. (Pill box or slide)

Question 16

Ornithodoros Soft tick

Answer 16

Capitulum (mouthparts) not visible dorsally and there is no scutum. Ornithodoros has a black mammillated integument (outer covering of the body) and pale cream legs. Six legs. The presence of the toothed hypostome (between antennae) and the Haller’s organ on first pair of legs distinguish this larva from a mite. And the lack of a segmented body distinguishes it from an insect. (Pill box or slide)

Question 17

Dermacentor Hard tick

Answer 17

Capitulum is visible dorsally and there is a small scutum in females and a large scutum in males. Dermacentor is usually ornate and has a rectangular basis capituli with short mouthparts.

Question 18

Anopheles Egg

Answer 18

Laid singly and possess floats. If you cannot see the floats, shut the condenser down to 2

Question 19

Aedes Egg

Answer 19

Laid singly, black oval shaped eggs. No floats present. Often with distinct pattern on outer cuticle

Question 20

Culex Larva

Answer 20

Siphon is usually long, with two or more subventral tufts that are not near the base.

Question 21

Aedes Larva

Answer 21

Siphon is usually short and has 1 pair of subventral tufts that occur more than 1/4 of the distance from the base of the siphon

Question 22

Mansonia Larva

Answer 22

Siphon is conical and ends in a sclerotized, saw-like process

Question 23

Simulium Larva

Answer 23

Cephalic fans, hourglass body shape with rectal gill. Antennae, eye spots, and gill may be seen

Question 24

Phlebotamine Larva

Answer 24

Enclosed pigmented head and a yellow or grey 12-segmented body. Paired caudal setae at tip of abdomen and characteristic matchstick hairs on the head and body

Question 25

Culicoides Larva

Answer 25

Looks worm-like, with a small, encapsulated head and a 12-segmented body. Terminal papillae may be retracted into abdomen

Question 26

Flea Larva

Answer 26

Small brown head on a 13-segmented pale brown body. The circle of setae on the posterior end of each segment and the pair of anal struts are very characteristic. Larva has no eyes

Question 27

Xenopsylla cheopis Flea (plague)

Answer 27

Antennal fossae not sclerotised (no headphones). No pronotal comb. No genal comb. Mesopleural rod present.

Question 28

Pulex irritans Flea

Answer 28

Antennal fossae sclerotised (headphones). No pronotal comb. No genal comb. No mesopleural rod.

Question 29

Ctenocephalides Flea (cat/dog)

Answer 29

Antennal fossae not sclerotised (no headphones). Pronotal comb. Genal comb. Mesopleural rod present.

Question 30

Tunga penetrans Jigger flea

Answer 30

Small round body shape with compressed thoracic segments. Upturned face, long serrated mouthparts. Enlarged spiracles.

Question 31

Pediculus capitis Head louse

Answer 31

Small wingless insect, dorso-ventrally flattened and covered in a leathery integument (tough outer protective layer). Males have rounded abdomens and genital apparatus on the dorsal side of the terminal segment, they also have an enlarged claw on the first pair of legs. The female abdomen ends in 2 lobes. Clothing and head louse species re morphologically identical. Differentiated by location on the host.

Question 32

Pediculus capitis Egg

Answer 32

Head louse egg: oval and white, with a low operculum. Egg will be glued onto a hair (as opposed to fabric with Pediculus humanus eggs) and even if removed from the hair, the glue will retain the shape of the hair strand.

Question 33

Pthrius pubis Crab louse

Answer 33

Small wingless insect with a compressed, rounded body shape. The division between the thorax and abdomen is less defined. Slender first pair of legs. Larger 2nd and 3rd pair of legs, with large claws.

Question 34

Cimex egg Bed bug egg

Answer 34

Smooth elongated egg with a clear operculum and a characteristic curve ~1mm long

Question 35

Triatomine Egg

Answer 35

Long and oval in shape, with a constriction just before the operculum. 1.5-2.5mm long.

Question 36

Ixodes Hard tick

Answer 36

Larva 6 legs and a scutum present. This differs from the soft tick larva, which does not have a scutum. The presence of the toothed typostome (between antennae) and the Haller’s organ on the first pair of legs distinguish this larva from a mite. And the lack of a segmented body distinguishes it from an insect.

Question 37

Trombiculid Mite larva

Answer 37

Scrub typhus/chigger mite larva: Reddish, orange or pale yellow mite with 6 legs, which terminate in a pair of claws. There is a compact capitulum and numerous setae covering the body and legs. There is also a weakly sclerotised scutum (very difficult to see) present, which has give feature setae and a pair of feather hairs called sensillae. Distinguished from the tick larvae by the lack of toothed hypostone and Haller’s organ.

Question 38

Sarcoptes scabiei Mite

Answer 38

Very round body, with short stumpy legs. Pulvilli on the 1st and 2nd pair of legs. 2 pairs of setae on the hind legs of the female (one pair on the male)

Question 39

Mosquito Pupae

Answer 39

Respiratory trumpets