FLEAS FROM BORNEO 
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length of the others (fig. 5, A.B ) Female typically with four antesensiliary bristles (fig. 9, A.B ), the 
second the longest, more than twice length of first and third; the fourth almost twice the length of first 
and third. 
Modified Abdominal Segments, Male (fig. 5). Eighth tergum ( 8 T . and fig. 3) with about five long 
caudomarginaUoristles; with about six median bristles between this row and spiracle; with a row of small 
bristles anterior to the above spiracle. Eighth sternum ( 8 S and fig. 10) about two and one-half times as 
long as broad at base, somewhat sinuate; apically slightly upturned, narrowing at distal third but apex 
ovate; proximal half of segment nude; ventral margin with a subapical long stout bristle; proximad to 
this another equally long bristle; with about 8 or 10 smaller lateral, submedian bristles scattered on 
remainder of distal half. Immovable process of clasper ( P . and fig. 11) about two and one-half times as 
long as broad at level immediately below acetabulum; apically subrounded, its anterior margin bearing 
five bristles, this row extended proximad by three or four additional smaller mesal bristles ; posterior margin 
with one fairly long thin apical bristle and a smaller subapical one. Movable finger or digitoid (F) long 
and narrow, about six times as long as broad, sides subparallel but slightly curving cephalad; caudal 
margin with four fairly stout bristles ; of these one is subapical, the second, somewhat stouter, is at proximal 
fifth, the third slightly distad of midpoint and the fourth at proximal third ; with two rather approximated 
long thin bristles both above and below the ventralmost of the four large ones. Manubrium (MB) and 
proximal arm of ninth sternum (P.A. 9) much as in S’, werneri. Distal arm of ninth sternum ( D.A . 9 and 
fig. 12) long and narrow, more than ten times as long as broad at midpoint; undifferentiated into proximal 
and ventral lobes or halves; with an apical stout bristle or subspiniform; with two long thin subapical 
bristles; immediately proximad one to three thin bristles; caudal (ventral) margin with three or four 
bristles at apical fourth, at shallow sinus; opposite these, with three or four anteromarginal bristles. 
Aedeagal apodeme ( AE.A ) somewhat longer than portion of aedeagus caudad of well-developed 
proximal spur (P.S and fig. 4); with a conspicuous pair of movable subdorsal lobes homologous to the 
distolateral lobes of Peromyscopsylla (Johnson and Traub) and herein also designated DL.L. Lateral 
lobes (L.L) prominent; with a deep apical sinus, ventrally fairly straight. Sclerotized inner tube with its 
apex (A.S.I) sharply upturned, talon-shaped. Armature of inner tube ( A.I.T ) represented as a short 
spur at base of sclerotized inner tube. Band of inner tube (B.I.T) sclerotized and extending distad of 
lateral lobes. Median dorsal lobe (M.D.L) weakly sclerotized. Crochet very long, much longer 
than aedeagal endchamber; more than about three and one-half times as long as broad at maximum. The 
lightly sclerotized dorsal wing convex; apex of crochet ovate; ventral margin straight below insertion of 
barrel-shaped or peg-like sclerite characteristic of Ceratophylline crochets. 
Modified Abdominal Segments , Female (fig. 9). Seventh sternum ( 7 S ) with caudal margin bearing a deep, 
fairly broad sinus, the resulting upper lobe irregularly but broadly rounded; ventral lobe slightly longer 
and broader, less rounded. Ventral portion of seventh sternum with a horseshoe-shaped row of about 
five or six stout bristles; three or four of these are caudomarginal and two or three ventromarginal. 
Anterior to this row a group of about five to seven smaller irregularly spaced bristles curving along ventral 
margin. Eighth tergum ( 8 T.) essentially as in 5 . werneri. Eighth sternum ( 8 S) weakly sclerotized but 
large, extending caudad to level of mesal group of three bristles near caudal margin of eighth tergum; 
devoid of bristles. Anal stylet ( A.S and fig. 7) about three times as long as broad; with two long stout 
apical bristles; a ventral bristle about one-third to one-half length of apical bristles; at times with a second 
ventral bristle subapical in position. Ventral anal lobe (fig. 2) more than two-thirds as broad as long; 
dorsal margin sinuate; ventral margin essentially convex, not angled, evenly merging with caudal margin; 
with a group of five or six bristles at height of convexity, i.e., where ventral and caudal angles merge; 
above this three or four long marginal bristles and two long submarginal bristles ; with a long submedian 
bristle, one or two short ones and three or four dorsomarginal bristles. Spermatheca (SP and fig. 6) with 
head longer than broad, dorsally convex; ventral margin concave; tail narrow, longer than head; tail 
slightly recurved apically but not extending over head. Bursa copula trix (B.C) ovate or pyriform, its 
ductus ( D.B ) well sclerotized, slightly curved. 
Types. — Holotype male and allotype female ex Rattus alticola. North Borneo, Mt. Kinabalu, 
Tenompok, elevation 4,500 feet; collected by Robert Traub, 2nd July, 1951. Paratypes as follows (all 
from Mt. Kinabalu, collected by R. Traub or with David H. Johnson in July, 1951): five males and 26 
females with same data as holotype; three males, six females ex Rattus rajah group, ibid. ; one male, one 
female ex Rattus whiteheadi, ibid.", one female each ex Rattus cremoriventer and R. infraluteus, ibid,", one 
female ex R. alticola, Lumu Lumu, elevation 6,300 feet, in the cloud forest; one male ex Tupaia montana 
baluensis and one female ex Rattus rattus baluensis, at Kamborangah, elevation 7,800 feet. Additional 
paratypes collected by J. R. Audy in June, 1952, loc. cit .: three males, three females ex Rattus alticola, 
Tenompok; two males and one female ex Rattus cremoriventer, ibid,", one male ex Rattus infraluteus, ibid. 
Holotype, allotype and four paratypes deposited in the L T .S. National Museum (Holotype, U.S.N.M. 
No. 61806). Paratypes deposited in the British Museum, the U.S. National Museum, the Canadian 
National Collection, the Chicago Natural History Museum, the Rocky Mountain Laboratory of the U.S. 
Public Health Service, the Plague Investigation Section of the U.S. Public Health Service, San Francisco, 
the author’s collection, and various other institutions. 
Comment. — Rattus alticola , a denizen of the mountain forest, is apparently the preferred 
host of Sigmactenus alticola. The known range of this flea is between 4,000 and 7,800 feet on 
MALAYA, No. 26 . 1953 
