- FELIS adult female

l'lletepimeron (slJppla.ntlng obdomlnal sternite I) abdominal \ 1ergites metathora~ ~ronotd\. cpmb rnesothora-x / (ctenld~) / ,...pronotum antepysidia.l '" // vertical r-odlike brlst[e \ ""//'---Sc.lerotization \ _- occipital regio" --fl"Ontal- epicranial t g,"oove ~~__dermal pit ...... -ocular bristle -­ e':le ......

groove IIa. \lar,! pa.lpus M pa.lpU5 rnopleura receptacvl~rl)! sosternum / semlniS \,j;-/ \- - mesepisternvm a17dominal I \ --mesepimcron sternites I 'COX~ I --rnet~sternum rn'etepis~ernum

L.._(JPt.:L. det~ched part of lIIete~sternvm

eral p\~tu bri~les

------4, ~ 1a.rsvs • .168

FLEA DIAGRAM - WITH STRUCTURES LABELED Harry D. Pratt

HEAD THORAX ABDOMEN I I I Prono!o' I comb I Antenna I Antepygidial Eye -bristles Ocular bristle --I--' -Pygidium

Femur Tibia

Plantar : PICTORIAL KEY TO SOME COMMON IN THE UNITED ST.ATES Harry D. Pratt Genal alld ..-101 Genal olld ..-tal combs 11"_1 combe obMftt

I I I I I I I Genal comb ofI 1I or mort G.nal comb Iof 4 lIMn•• labial polps nol '"­ Labial polps '"­ Fronl maroln of Fronl maroln of 11M"'. E,. pr...nl E,. absenl lelldlno be,ond I ro­ lelldino be,ond Iro­ head round.d head onoulor chonl.r of fl"1 1'0 chonl.r of first 1'0 Thorol norma I Thoral conlracl.d

~ ,­ I ~LAbiOI polp I I G.nol comb G_I comb FlEA STICKTIGHT FLEA horlzonlol vertical Ola_ EchldllO(JMga Spinet poInl.d Spinet blunl lfIafIfa_ (ItIIliMC«1

Seom.nI 1I of !ieomenl 5 of hind Mesopleuron not MetIopIeuran divided hind __wiIh tar.. with I polr divided III' vertical III'vertical rodlike 5 pol" loleral ventral (basal) GIld Ihk:lulnino Ihiei

Ocular bristl. in­ Oculor brislle insert.d sertld bllow eye In fronl of eye

~THERN RAT FlEA SQUIRREL FLEA (]l (D Nosopsyllus OrchopNs XMIOPSY"a fascia/us howordii cMopis • FLEAS: PICTORIAL KEY TO SPECIES FOUND ON DOMESTIC RATS IN SOUTHERN UNITED STATES • Sliqhll, r.....d .April 1947 ~ Genal, Pronatal and Genal and pronotal 8, Ror ~ Frill and _" o. Pr." Pronotal comb No combs abdominal combs pre..nt combs present Rev. Morch. 19$ 4 present present

~I ~I ~I I I I bristles 2 rows of bri,tles Thorax normal Thorax contracted I I an typical abdomi­ Front maroin of Front maroln of Genal comb of five or more nal seoment head rounded head anoular spines. Eye-, present. • • • ~ I i i i I I I Labial palps not ex­ Labial palps ex­ 2 rows of bristles Genal comb Genal comb Genal comb tendino beyond tro­ tendino be'yond on typical abdomi­ horizontal with 4 spines with 2 spines chanter of first pair trochanter of first nal seoment SPlne'rinted of leos • pair of •leos

'-----'''-_--' CrENOPHrHALMUS PSEUDAGYRrES I I I I I Head lenqth nat Head lenoth Seoment !5 of Seoment!5 of hind MesQPIeuran not Mesoplluran divided twice WIdth twice width hind tarsi with tarsi with I pair divided by vertical by vertical rodlike 5 pairs lateral ventral (basal) and sclerotization. sclerotizat ion. , , plantar bristles 4 pairs lateral • • ~'i ~i ,~,,'":to~:"l';:,"" [Tr;{da ~ tit Spine I of oenal Soine I and spine PLANTAR ~ ~SOPLE~ comb distinctly n of oenal comb BRISTLES shorter than approximately equal Ocular bristle in­ Ocu lor bristle innrt­ spine II in lenoth serted below eye ad in fran t of eye crENOCEPHALIDES CrENOCEPHALlDES 4¥ CANIS FELIS 171.

FLE:AS: ILLUSTRATED KEY TO SPECIES FOUND DURING PL.AGUE INVESTIG.ATIONS Harry D. Pratt and Chester J. Stojanovich 1. Pronotal and genal combs absent (Fig. 1 A) ...... 2

Pronotal combs present; genal comb present or absent (Fig. 1 B & G) •..S

Fig. 1 A 1 B Fig. 1 C 2. Front margin of head with two angles; three thoracic tergites together shorter than the first abdominal tergite (Fig. 2 A). (£chidnophaga gallinacea) ...... •...••.•STICKTIGl{T FLEA

Front margin of head rounded; three thoracic tergites together longer than the first abdominal tergite (Fig. 2 B) ...... 3

labd I

Fig. 2 A Fig. 2 B 3. Ocular bristle in front of eye; mesopleuron divided by internal sclero­ tizationj female with spermatheca partially pigmented (Fig. 3 A & B) ...... • (Genus Xenopsylla) •..••.....4

Ocular bristle beneath eye; mesopleuron without internal sclerotization; female with spermatheca entirely without pigment (Fig. 3 C & D) ...... (P\!lex irritans) ...... HUMAN FLEA

Fig. 3 A Fig. 3 B Fig. 3 C Fig. 3 D .172

4. Genus Xenopsylla --­

cheopis

astia " " ,, , , , ,

vexabilis hawaiiensis

Xenopsylla cheopis, male terminal segments.

,,­ ,,­ ,/ X. brasiliensis

,/ ,/ ,/ ,/ ,/ ,/

------1£. astia

------1£. vexabilis hawaiiensis Xenopsylla cheopis, female terminal segments 173.

5. Genal comb absent (Fig. 5 A) ...... ~ .....6

Genal comb present (Fig. 5 B) ...... ••...8

, ,, genal,' _, Fig. 5 A Fig. 5 B comb(..- ­

6. Pronotal comb with about 12 teeth on each side (Fig. 6 A). India ...... Stivalius ahalae

Pronatal comb with 5 to 10 teeth on each side (Fig. 6 B) ...•...... 7

Fig. 6 B

7. Labial palpus long, ex ing beyond trochanter of first leg (Fig. 7 A). Diamanus montanus ...... ROCK SQUIRREL FLEA

Labial palpus short, not extending to tip of coxa of first leg (Fig. 7 B). Nosopsyllus fasciatus ...... •••...... •...NORTHERN RAT FLEA

Fig. 7 A Fig. 7 B labial palpus __ _ trochanter__ -- -­

labial palpus_____ .,74

8. Genal comb with two teeth (Fig. 8 A) ••••••.•••..•..••••• (Genus Neopsylla) Neopsylla setosa important in U. S. S. R., Mongolia and Manchuria.

Genal comb with three teeth (Fig. 8 B) ••••••••••••• (Genus Ctenophthalmus) Ctenophthalmus breviatus and pollex potential vectors in U. S. S. R.

Genal comb with four teeth (Fig. 8 C) .•..•.••..••••••• (Genus Leptopsylla) Leptopsylla segnis is cosmopolitan.

Fig. 8 A Fig. 8 B Fig. 8 C

Genal comb with more than five teeth•...... •. (Genus Ctenocephalides). 9

9. Head strongly rounded anteriorly; first spine of genal comb about half as long as second; hind tibia with the spiniform setae A and B (Fig. 9 A & B). Ctenocephal ides canis .••••..•..•...... •.... ;.•...... •.... FLEA

Head not strongly convex anteriorly; first spine of genal comb almost as long as second spine; hind tibia with spiniform seta B, spiniform seta A replaced by a minute seta which may be absent in some specimens (Fig. 9 C eSc D). Ctenocephal ides fel is ...... •...•....••......

Fig. 9 D