Veterinary Entomology 208
Spring 2010

Magnification
• Always start at lowest
magnification (lowest power
objective)
• Move to higher objective as
necessary (3-4 stations only)

Focus
• Adjust width of oculars
• Adjust coarse, then fine focus
• If on the highest magnification,
only adjust the fine focus to
avoid breaking slide

Light
• Use condenser to adjust
amount of light (dark vs. glare)
• Higher magnifications may
require more light
 Be
sure you read where the key is sending you
next, as it can get confusing (particularly with
lice)
 Look
at arrow on insect to see what
characteristic is being studied
• The small arrows in the key indicate the structure
referenced in the couplet
Fleas (Siphonaptera)
6
specimens:
1. Ctenocephalides felis
2. Leptopsylla segnis
3. Nosopsyllus fasciatus
4. Echidnophaga gallinacea
5. Pulex irritans
6. Xenopysylla cheopis
receptaculum
seminis
In front of eye
Below eye
Key
 1st couplet: number of combs
• We don’t have a 3 comb flea
 2 comb fleas:
• Eye presence/absence will separate these 2
species
 1 comb flea:
• There is only one in our set
 0 comb fleas:
• Head shape separates out Echidnophaga
gallinacea
• Ocular bristle position separates the other 2
species

12 specimens of
Mallophaga:
1.
2.
3.
4.
5.
6.
7.
8.
Heterodoxus spiniger
Menacanthus
stramineus
Menopon gallinae
Chelopistes
meleagridis
Goniodes gigas
Goniocotes gallinae
Goniodes dissimilis
Lipeurus caponis
Felicola subrostrata
10. Bovicola crassipes
11. Bovicola bovis
12. Bovicola limbata
9.
 10
specimens of
Anoplura:
1. Pediculus humanus
2. Phthirus pubis
3. Haematopinus suis
4. Haematopinus asini
5. Haematopinus
eurysternus
6. Solenopotes
caplillatus
7.
8.
9.
10.
Linognathus
africanus
Linognathus setosus
Linognathus pedalis
Linognathus vituli