Dr. Kassai Tibor szerk.: Parasitologia Hungarica 2. (Budapest, 1969)

5 On the Coexistence of Fleas (Siphonaptera) on Mammals in Hungary István SZABÓ Zoological Department of the Hungarian Natural History Museum, Budapest • • • Several papers dealing with the natural history of fleas record the common occurrence of several flea species on one host-species. These communications usually refer to all the flea species occurring on several individuals of the host species and only rarely does a paper consider the flea population found on a single host specimen (or in their nests, burrows, etc.). In my opinion it would be more informative if the flea populations were evaluated on the basis of single individuals of the same host species, because the constant haunts of animals the location of their nests, the conditions of their é.ssociutions with other neighbouring species, and so on, differ even within a small area of the habitat, and all these factors influence the common occurrence of flea species. • . The common occurrence of flea species aroused my interest some time ago. Examining.my material collected from 1958 till the end of 1967, I found that although given host, usually carries a single flea species the common occurrence of several flea species is not rare.On one host species (or in its nest, material), I found one flea species in 66.5 per cent of cases, two In 26.8 fo, three in 5.8 and 4 in 0.9 Since in one-third of the cases more than one flea species was found to occur on a host specimen, a study of the conditions of coexistence neemed