The comparative host status of red veld rats (Aethomys chrysophilus) and bushveld gerbils (Tatera leucogaster) for epifaunal arthropods in the southern Kruger National Park, South Africa

Abstract

Red veld rats (Aethomys chrysophilus) and bushveld gerbils (Tatera leucogaster) were trapped at monthly intervals, when possible, over a 2-year period, in the southern Kruger National Park, Mpumalanga Province. Forty-six specimens of each species were caught, euthenased and microscopically examined for fleas, lice, ticks and mites. Clear differences existed between the two rodent hosts in infestation intensity and also parasite species. The flea, Xenopsylla brasiliensis, commonly and exclusively utilized red veld rats, whereas Xenopsylla frayi was common and specific to bushveld gerbils. T leucogaster were commonly infested with the lice Hoplopleura biseriata and Polyplax biseriata, while only a single A. chrysophilus hosted the louse, Hoplopleura patersoni. Red veld rats harboured small numbers of the immature stages of Haemaphysalis leachi / spinulosa and relatively large numbers of Rhipicephalus simus. The larvae of R. simus were irregularly collected from February to September and the nymphs from March to November. Bushveld gerbils hosted fewer ticks than did the rats, with a single specimen of H.leachi / spinulosa and low numbers of immature Hyalomma truncatum, the latter erratically present from June to October. Mites were abundant on both rodent hosts, A. chrysophilus hosting 13 species in six families, and T leucogaster hosting 12 species representing seven families, with clear differences in mite assemblages between the two rodents. As the rats and gerbils were collected from the same trap lines at the same times, the differences in species composition and infestation intensity of their parasites, suggest that immunological, behavioural or other segregating mechanisms are in operation to maintain discrete parasite assemblages.