NO. 4 FLEA GENUS PEROMYSCOPSYLLA — JOHNSON AND TRAUB 5I 



PEROMYSCOPSYLLA OSTSIBIRICA OSTSIBIRICA (Skalon, 1936) 



Figures 122, 123 



Leptopsylla ostsibirica Skalon, Izvest. Gosudarstv. Inst. Siberia i DVK, vol. 4, 

 pp. 48, 52, 55, 1936; Materialy K. Poznaniiu Fauny i Flory S.S.S.R., n. s., 

 Zool., No. 15 (XXX), Ectoparasites, II, pp. 74—84, 1950, Moscow. 



A translation of Skalon's 1950 description and the type distribution 

 is as follows : 



Female and male. This species is closely related to the European species 

 L. bidentata K. and the North American L. haviijer R. Prefrontal row consists 

 of nine to eleven bristles arranged all along the length of frons. The fourth and 

 fifth of these (from above) are much thickened; the sixth is less modified and 

 seems intermediate between the preceding bristles and those that follow, which 

 are fairly long and of the usual shape. Head ctenidium consists of two teeth, 

 pronotal ctenidium of 25-28 teeth. Abdominal tergites from the first to the 

 sixth inclusive have many chitinous apical teeth ; the number varies greatly, 

 but the average is S.6,5,3,3,2. Male has three antepygidial bristles (in one case 

 three bristles were found on one side and two on the other) ; female has five to 

 seven. All the antepygidial bristles are set in one row, long ones alternating 

 with short ones. Lateral surfaces of posterior femora have at the base one 

 bristle on the outer side and one or two on the inner, at the apex two or three 

 on outer side and one on inner. 



Male. Apical lobe of eighth sternite (fig. 5) [our fig. 122, 88.] has its poste- 

 rior margin cut away in a straight line, and its ventral angle projects sharply 

 downward ; along posterior margin there are three long bristles and three smaller 

 ones. Base of apical lobe has one strong ventral bristle on each side. Immovable 

 finger [P.] is long and wide, with rounded apex; its posterior margin has con- 

 spicuous bristle below the first third. Movable finger [F.] is regular and tri- 

 angular in shape; three large bristles are placed at the apical angle, which is 

 almost a right angle. There are some small bristles on the upper margin, which 

 is almost straight, and the posterior margin, which is slightly concave. Manu- 

 brium of clasper is wide in basal half and narrows unevenly farther on. Distal 

 part of horizontal branch of ninth sternite [D.A.9] has its ventral and dorsal 

 margins almost parallel ; ventral margin has many small bristles on its basal 

 third and three strong bristles at almost the same distance farther on; apex is 

 obliquely cut away, with angle projecting upward and margin set with small 

 bristles. 



Female. Apical margin of seventh sternite of female (fig. 6) [our fig. 123] 

 has a deep lateral indentation dividing the wide rounded ventral lobe from the 

 dorsal, which projects over this indentation and looks like a long, straight beak. 

 Lateral surface of sternite has a regular row of seven to nine large bristles and 

 one to three small ones. 



Length 2.3-3 mm. We found a series of specimens of this species, six female 

 and five male, around the Alexandrov plant (eastern Transbaikal). The species 

 is adapted to parts of the forest, and was found on Evotomys riitilus and rufo- 

 catvus, or Microtus ungurensis and mongolicus. Also it has been found in con- 

 siderable numbers around Kabansk (eastern Baikal) in forest steppe country 

 on Evotomys rutilus and rufocanus, Microtus michnoi and ungurensis, and 



