Lab Exercises
ORDER DIPTERA (Flies)
Suborder Nematocera (the "long-horned" flies)
Click here for a diagram of long-horned fly antennae types.
Family Culicidiae (Mosquitoes)
Mosquitoes are tiny delicate flies the females of which, in most cases, require a meal of vertebrate blood to stimulate and support egg development. Like the other true
flies, developing mosquitoes undergo complete metamorphosis progressing through EGG, LARVAL, PUPAL, and ADULT stages. The immature stages are aquatic.
Simulium sp. (a.k.a. Black flies)
|
|
|
Simulium sp.
Larva (center) and pupae (right and left). These stages are adapted to life in swift moving streams. |
Simulium sp. adult |
Simulium sp.
Diagram of antenna and mouthparts |
|
|
|
Simulium sp. (Black fly) eggs |
Simulium sp. larvae
The posterior end (to the right) would be attached to a rock at the bottom of the stream and the mouthparts on the anterior end (left) filter out food from the water column. |
Simulium sp. pupae
The filaments on the anterior end are used for breathing. |
Top of the Page
Suborder Brachycera (the "short-horned flies")
This group includes the horse flies and deer flies.
Tabanus sp. - horse fly
|
Tabanus sp. (Horse Fly) Adult |
|
Diagram of the short, indistinctly segmented antenna of flies in Family Tabanidae and Suborder Brachycera. Their wings have a roughly hexagonal discal cell and a branching third vein. The veins in the wings allow an
entomologist to identify the fly to genus. |
 |
Mouthparts of a horse fly. The fly feeds by using its lacerating mouthparts to produce a pool of blood on the skin of its host. The blood is then lapped up by the labium. |
Top of the Page
Suborder Cyclorrhapha (the "muscoid" flies)
Musca sp. and Lucilia sp. and other muscoid flies are sometimes
involved in facultative myiasis.
Click here for a diagram of the muscoid larvae spiracle characteristics.
Gastrophilus sp. - horses
Click here for a diagram of Gastrophilus eggs.
|
|
Gastrophilus spp. (Stomach Bot) Larvae
In both figures G. nasalis is on the left and G. intestinalis on the right.
Note the double row of spines on each segment of G. intestinalis and
the single row on each segment of G. nasalis. |
|
Equine Stomach Bot Larvae in situ.
G. intestinalis (left, favoring the cardiac region of the stomach) and G. nasalis (right, attached near the pylorus). |
Top of the Page
 |
Adult Stomoxys calcitrans "stable fly"
Note the proboscis, which is held stright out from the head when the fly
is not feeding on a host's blood. |
 |
Resting areas for various flies on cattle. |
Oestrus ovis: sheep (a.k.a. Sheep Bot Fly)
 |
Oestrus ovis larvae |
Cuterebra sp.: rodents, rabbits, (occasionally) dogs and cats
|
|
adult Cuterebra sp. |
Cuterebra larvae
removed from the
subcutaneous tissues of a rodent |
Hypoderma sp.: livestock
|
|
|
adult Hypoderma bovis
(a.k.a heel fly or warble fly)
Note the bee-like appearance.
The mouthparts are vestigial as the adults do not feed. |
Hypoderma sp. (cattle grub)
Found in subcutaneous pockets on the back of the host. |
Damage to leather due to larval stages. This piece of leather is unusable and thus represents an economic loss to the rancher. |
Top of the Page
Melophagus ovinus: sheep
| adult Melophagus ovinus |
 |
 |
Melophagus ovinus adults and pupae in the wool of a sheep. The adult females give birth to 3rd instar larvae which rapidly form their pupal cases. |
ORDER SIPHONAPTERA (Fleas)
Click here for Flea
Identification Exercise 1 and Exercise 2
|
|
|
Adult flea |
Flea larva
Note the gut is dark red because the larva has been eating the feces of the adult flea which contains the hemoglobin from the blood meal |
Flea larvae in their natural habitat (the base of a rug).
Larva (green arrow)
Egg (yellow arrow)
Flea dirt [feces] (red arrow) |
Ctenocephalides felis: cats and dogs
 |
 |
Ctenocephalides felis (left)
Note the first tooth of the genal comb is as long as the second.
Ctenocephalides canis (right)
Note the first tooth of the genal comb is shorter than the second. |
Click here to link to the Ctenocephalides canis (and felis) life cycle.
Echidnophaga gallinacea (a.k.a. sticktight flea): poultry
 |
Adult Echidnophaga gallinacea |
 |
Top of the Page
ORDER PTHIRAPTERA (Lice)
Suborder Mallophaga (Chewing Lice)
Ischnocera - Antennae stick out from head
Trichodectes canis: dogs
 |
Trichodectes canis adult |
 |
Trichodectes canis eggs and adults in the hair of a dog |
 |
A louse egg (a.k.a. a "nit")
These are glued onto a hair shaft of the host. |
Damalinia sp.: livestock
 |
Damalinia caprae (goats)
Notice the chewing mouthparts grasping the hair
and the easily visible 3 segment antennae |
Amblycera - Antenna in pits on side of head
Menopon gallinae (a.k.a. shaft louse): poultry
 |
Menopon gallinae adult |
|
Head with antenna recessed into a groove on the side of the head (a characteristic of the Amblycera). |
|
Menopon gallinae in situ |
Top of the Page
Suborder Anoplura (the sucking lice)
Haematopinus sp.: swine
 |
Haematopinus sp. |
Linognathus sp.: dogs
 |
Linognathus sp. |
Phthirus pubis and Pediculus humanus: human (dogs and cats DO NOT act as vectors for human lice)
 |
Human lice
Pediculus humanus (left)
Phthirus pubis (right)
|
 |
Top of the Page
|
