Parasites of two abundant sympatric rodent species in relation to host phylogeny and ecology

In the present study, two abundant sympatric rodent species ( 27 Apodemus flavicollis and 33 A. sylvaticus) were studied for their endo- and ectoparasite fauna. The rodents were trapped in Dormagen, a city in North Rhine - Westphalia, Germany. A total of 20 different parasites species were identified, 13 endoparasite ( 2 Digenea, 5 Cestoda and 7 Nematoda) and 7 ectoparasite ( 5 Insecta and 2 Arachnida) species. Thirteen parasite species were found inhabiting both rodent species. The predominant endoparasite species in both rodents was the nematode Pelodera strongyloides, followed by the nematode Heligmosomoides polygyrus and a Syphacia species. The flea Ctenophthalmus agyrtes was the dominant ectoparasite in both rodent species. A. flavicollis usually carried 1-7 ecto-/endoparasite species ( mean 4.0), whereas A. sylvaticus were mostly infested with 1 - 9 ( mean 4.4). The parasite diversity of A. flavicollis (H'= 0.268, J= 0.097) was marginal lower in comparison to A. sylvaticus (H'= 0.319, J= 0.110). The two rodent species examined show remarkable similarities in the composition of their endo- and ectoparasite fauna being directly related to their similar pattern of living in the investigated area.