104 MISC. PUBLICATION 5 0, U. S. DEPT. OF AGRICULTURE 



Xenopsylla includes a large number of closely related species, some 

 of which should probably be considered more appropriately as varie- 

 ties. Originally it apparently was confined to Africa, or to Africa 

 and western Asia. Through commercial activities some of the species 

 have been introduced into Europe and the Western Hemisphere as 

 well as into various parts of Asia. 



Xenopsylla cheopis (Rothschild) 

 (Fig. 12, D and G) 



Pulex vheopis Rothschild, 1903, Ent. Monthly Mag. (2) 14 : 85, pi. 1, figs. 3, 9; 



pi. 2, figs. 12, 19. 

 Xenopsylla cheopis Rothschild, 1909, Novitates Zool. 16: 132. 

 Loemopsylla cheopis Jordan and Rothschild, 1908, Parasitology 1: 42. 



Cotype hosts. — Seven hosts were indicated by Rothschild in his 

 original description. 



Type locality. — Shendi, Egypt. 



Range. — Although this species is not cosmopolitan in its distribution, 

 it has been very widely disseminated through the introduction of 

 its favored hosts into many countries. However, since much of its 

 life cycle is spent detached from the warm bodies of the hosts, this 

 more or less tropical species apparently has not been able to follow 

 them into all the areas they have invaded. 



The distribution of Xenopsylla cheopis, or the oriental rat flea, in 

 the United States is interesting. For many years it was reported 

 only from the larger port cities, where it frequently made up a con- 

 siderable percentage in the total rat flea population. In 1925, how- 

 ever, F. N. Wallace (88) reported finding cheopis on rats in Indian- 

 apolis, Ind., but noted that no infestation of houses was observed. 

 About this time W. A. Riley identified a specimen from St. Paul, 

 Minn., taken from a rat. Then, in 1934, Roudabush and Becker (68) 

 reported the finding of many specimens of cheopis on rats shot on the 

 dumping ground of the city of Ames in Iowa. The}' called attention 

 to the statement of C. Fox (23, p. 133) in 1925 that the oriental rat 

 flea was not known to occur in the interior of the United States. This 

 infestation at Ames has continued since the observations of Rouda- 

 bush and Becker and constitutes, as far as known, a permanent in- 

 festation. In 1939 Roudabush (67) also recorded the flea from Des 

 Moines, Iowa. Owen (60), in 1936, reported an infestation of a dairy 

 barn at the University of Minnesota Farm, St. Paul, Miim., and in 

 1938 the present writers, Ewing and I. Fox (19), added new records 

 from Illinois and Ohio. Trembley and Bishopp (76) reported the 

 species from Nashville, Tenn. The specimens came from rats 

 captured in a grain store in the city near the Cumberland River in 

 March 1938. These authorities have reviewed their United States 

 records, as well as those from the literature, and find that Xenopsylla 

 cheopis has now been reported from 19 States and the District of Co- 

 lumbia. Of these 19 States, 13 are coastal with ports for foreign 

 commerce. The scattered records of this flea from the interior States 

 are of recent date and indicate the establishment of "islands" of in- 

 festation, in a region the climate of which might be thought adverse 

 to their existence. 



Xenopsylla cheopis has been much studied, but only a few refer- 

 ences to the literature dealing with it can be given here. Bacot (1) , in 



