Comments on Ectoparasites of Two Species of Microtus in Nebraska

The ectoparasitic fauna of Nebraskan Microtus pennsylvanicus and Microtus ochrogaster was examined to determine what species were present, the relative abundance of each species, sex, and developmental stage. Four species of mites of the family Lab lapidae were found. Hyperlaelaps microti, the most abundant ectoparasite collected, and Androlaelaps fahrenholzi were obtained from both species of voles. Hirstionyssus isabellinus is reported from Nebraska for the first time on the basis of three specimens taken from M. pennsylvanicus. One adult female Hirstionyssus utahensis was collected from M. ochrogaster and constitutes the first record of this mite for Nebraska and on M. ochrogaster. Dermacentor variabilis, the American dog tick, was the only tick taken during the study. Two species of fleas, Epitedia wennmani and Monopsyllus wagneri, were found on M. pennsylvanicus. The single species of louse obtained, Hoplopleura acanthopus, was collected only from M. pensylvanicus and is herein initially reported from Nebraska. Trans. Kans. Acad. Sci., 75 (1), 1972. Introduction Several articles have been published describing ectoparasites and their distribution on mammals, but little of this wor] has been done in the Great Plains region. Allred (1958) described mites on five species of Peromyscus in Utah. KinseIla and Pattie (19G7) studied ectoparasites of small mammals, including Microts montangs and Arvicold richardsoni, from the Beartooth Plateau in Wyoming. Populations of lice on Peromyscws maniculatus, Microtus pennsylvanicus, and Clethrionomys gapperi in Minnesota were studied by Cook and Beer (1955; 1958). In a review of the natural history of the prairie vole, Jameson (1947) included a list of the ectoparasites collected from Microtus ochrogaster in Kansas. Rapp (1962) listed seven species of mites found on birds and mammals in Nebraska and Rapp and Gates (1957) published distributional notes for fleas obtained from Nebraskan Peromyscgs and Blarina. Considering the paucity of information on mammalian hostectoparasite relationships, I felt that a more comprehensive study of the ectoparasitic fauna associated with MicroSs pennsylvanic?Ws (Ord) would 42 T>aszJactiozls of the KaszJas Aradem) of Ssie>ce be elucidative. The purposes of this research were to determine what speciebs of ectoparasites occur on l1. peZr7XS1zaelics and to estimate the relative abundance of cach sex and developmental stage for each ectopara-