MALAYSIAN PARASITES XI 
SIGMACTENUS ALTICOLA and NEOPSYLLA LUMA , NEW SPECIES OF FLEAS 
FROM NORTH BORNEO 
By 
ROBERT TRAUB 
During investigations on arthropod vectors and rodent reservoirs of disease, a joint U.S. 
Army and British Colonial Ofhce Unit research team operated in North Borneo in July and 
August, 1951. A second such unit continued the studies in May and June of 1952. In 
connection with these studies, many valuable fleas, mites and ectoparasites were collected from 
small mammals, particularly on Mt. Kinabalu. Among the fleas taken were a new species of 
Sigmactenus Traub, 1950 (Ceratophyllidae, Leptopsyllinae) and an undescribed species of 
Neopsylla Wagner, 1903 (Hystrichopsyllidae, Neopsyllinae), described and illustrated below. 
Sigmactenus alticola n. sp. (figs. 1-12). 
Diagnosis . — Near the genotype, 5 . werneri Traub, 1950, which has been described and 
illustrated in detail, but separable as follows : Male eighth sternum (fig. 10) much more narrowed 
subapically and bearing two long subapical bristles instead of being of approximately uniform 
width to near apex and bearing a distal marginal group of four bristles scarcely longer than 
adjacent lateral bristles. Distal arm of male ninth sternum (fig. 12) lacking a distinct median 
lobe bearing a prominent tuft of dark bristles ; with fewer lateral and ventromarginal bristles, 
i.e., the marginal bristles only about four in number and these near middle of arm, whereas in 
S. werneri about 20 bristles extend along or near the entire ventral margin. Aedeagal crochet 
(fig. 4, CR ) narrower, dorsally more arcuate, apex subrounded; not angulate dorsally and 
subacuminate apically. Female seventh sternum (fig. 9, 7S) with upper lobe typically shorter 
than ventral one, instead of vice versa. Anal stylet of female (fig. 7) three times as long as 
broad, instead of merely twice as long as broad. 
Description. — Head (fig. i, Male). Pre-antennal region with three long bristles, the uppermost 
inserted next to base of first (topmost) genal spine at level of minute frontal tubercle; remaining two 
bristles in a vertical row; of these the uppermost usually at level of fifth or sixth genal spine, near midpoint 
of comb; third bristle median, at level of third or fourth spine. With a marginal clypeal row of five to 
seven small thin bristles, interspersed among submarginal sclerotized lattice-work or incrassation 
characteristic of genus ; with a row of about six small bristles on the frons ranging from level of uppermost 
spine of comb to top of head, above and in front of the vestigial eye (E) which, as in other species of the 
genus, has been pushed to near top of head by hyperdevelopment of genal ctenidium. Genal comb with 
spines varying in number from 9 to 11. Maxillary lobe extending to near apex of third segment of 
maxillary palpus. Labial palpi five-segmented extending to slightly less than three-fourths length of 
forecoxae. Male antenna with first segment bearing a small dense tuft of bristles above dorso-apical 
angle; the tuft lacking in female. Bristles of second antennal segment very short in male, not extending 
beyond proximal third or fourth of club; in female one bristle of this segment reaches beyond apex of club. 
Antennal club in male appearing to be secondarily divided so that club seems to have 15 to 17 segments if 
dorsal (anterior) divisions are counted rather than ventral. Postantennal bristles usually arranged 4-3S-6 
but with one or two additional bristles placed between first two rows. 
Thorax. Pronotum with two rows of bristles and a comb of about 11 or 12 long thin spines per side. 
Portion of pronotum bearing longest and lowest bristle of second row overlapping prosternosome 
Mesonotum (Fig. 8, MSN) with three rows of bristles and three pseudosetae ( PS.S ) per side; two 
pseudosetae subdorsal and one ventral. Mesepisternum ( MPS ) with about three to five bristles. 
Mesepimere ( MPM ) usually with six bristles, arranged 3-3. Metanotum ( MTN ) with three rows of 
bristles; its flange with an apical tooth on each side. Lateral metanotal area ( L.M ) well demarcated; 
with two bristles. Metepisternum (MTS) with a single subdorsal bristle; squamulum well developed. 
Pleural arch (PL. A) strongly convex well developed. Metepimere (MTM) usually with about eight or 
nine bristles, arranged 4 (5)-3-i; spiracles subglobose. 
Legs. Essentially as in S’. werneri. 
Abdomen. Small subdorsal teeth on posterior margins of first few segments usually arranged as follows : 
Male, 2-2-2- 1 -1 (per side); female, 2-2- 1-1. Male with middle antesensiliary bristle almost thrice the 
STUD. INST. MED. RES. 
