Ecological factors shaping ectoparasite communities on heteromyid rodents at Médanos de Samalayuca

Rodent ectoparasites are vectors for important pathogens of wildlife, domestic animals, and even zoonosis. Nevertheless, distribution patterns of ectoparasites are not fully understood; habitat, season, and host species are important predictors of distribution and prevalence. Heteromyid rodents are considered important reservoirs of diseases, given the presence of different ectoparasites and pathogens in them, and they offer the opportunity to learn about the ecology of parasites. The aim of the present work was to survey ectoparasites associated with heteromyid rodents near a National Protected Area in Chihuahua Mexico, south of the USA-Mexico border, and asses the effects of ecological factors (season, vegetation type, host species, and host body condition) on parasite infestation. We sampled five different locations from January 2018 to July 2022; 845 heteromyid rodents were examined and 49 fleas and 33 ticks were collected. Ectoparasites belonged to the Siphonaptera and Ixodida orders, including three families Ixodidae ( Riphicephalus sanguineus ), Pulicidae ( Pulex irritans ), and Ctenophthalmidae ( Meringins altipecten , M. dipodomys ). Five species of host rodents were captured, Dipodomys merriami , D. ordii , Chaetodipus eremicus , C. hispidus , and C. intermedius , but the last two species did not present any ectoparasites. Dipodomys merriami presented the highest flea and tick prevalence followed by D. ordii . We found parasitic partnerships between heteromyids according to ecological factors. The infestation in C. eremicus was related to body condition, vegetation type, and sex; in D. merriami , it was related to vegetation type and season, while D. ordii did not present a clear pattern of infestation. Our results suggest that the infestation patterns of heteromyid rodents in desert habitats are species dependent.