68 
The Non-Conibed Eyed Siplionaptera 
Key to the species of Rhopalopsyllus. 
a. Labial palpus consisting of 6 or 7 segments .....b 
Labial palpus consisting of 5 segments .c 
b. Metanotum with 3 rows of bristles .Species No. 1 
Metanotum with 2 rows of bristles.Species No. 2 
c. Rostrum extending beyond the trochanter . .Species No. 10 
Rostrum extending to the apex of the forecoxa or being shorter.d 
d. Occiput with 2 rows of bi’istles .Species No. 11 
Occiput with 3 rows of bristles.e 
e. Anterior edge of pygidial plate much raised, projecting ; fifth segment of all 
tarsi long, dilated towards apex, that of foretarsus larger than the second midtarsal 
segment.f 
Anterior edge of pygidial plate slightly raised ; fifth tarsal segment short, in 
hindtarsus about as long as the second midtarsal segment .h 
f. Basal abdominal sternite with 2 lateral rows of small bristles .g 
Basal abdominal sternite with 3 or 4 irregular lateral rows of small bristles. 
Species No. 5 
g. Hindtibia with 2 or 3 bristles on the inner surface .Species No. 3 
Hindtibia with 4 or 5 bristles on the inner surface .Species No. 4 
h. Midtibia with numerous bristles scattered over the outer surface as on the 
foretibia. Clasper of $ with 3 long bristles below the tip .i 
Midtibia with one lateral row of bristles on the out- and inside. Clasper of $ 
with 2 bristles below the tip.Species No. 12 
i. Hindcoxa with 2 bristles posteriorly near the apex ; the long bristle situated 
in the fourth notch of the hindtibia extending beyond the apex of the tibia. 
Species No. 9 
Hindcoxa with 3 bristles posteriorly near the apex .k 
k. Metanotum with 4 rows of bristles, the anterior row consisting of about 
6 bristles .Species No. 6 
This fourth row of bristles of the metanotum absent, or represented by 1 or 2 
bristles only.1 
l. The bristles situated below the tip of the ninth sternite (£) very numerous; 
movable process of clasper short .Species No. 8 
The bristles situated below the apex of the ninth sternite (£) more evenly 
distributed ; movable process of clasper long and slender .Species No. 7 
(1) Rhopalopsyllus cleophontis Rothsch. (1904). 
(PL II, figs. 3, 9; III, fig. 10; VI, fig. 7.) 
Pulex cleophontis Rothschild (1904 a, p. 614, n. 9, t. 10, fig. 32, Buenos Ayres, oil' 
Muletia septemcincta). 
Rhopalopsyllus cleophontis Baker (1905 a, pp. 130, 143). 
The largest known species of this genus, apart from R. lutzi. The 
bristles on the body are somewhat thin for the size of the insect. 
