Hyperparasitism and Non-Nidicolous Mating by Male Ixodes angustus Ticks (Acari: Ixodidae)

Ixodes angustus (Neumann) (Acari: Ixodidae) is considered to be a nidicolous tick in that the entire life cycle can be completed in the host nest. Males of this tick have been reported to be rare on hosts because most mating occurs in the host nest and males typically do not feed on hosts. Collections of I. angustus in Alaska departed slightly from this paradigm in that nine males were collected from hosts, mostly in copulation with females that were attached to mammalian hosts. Non-nidicolous mating was therefore more common in I. angustus collected in this study than has been reported previously. A hyperparasitic male I. angustus was found firmly attached via its hypostome and chelicerae to the ventral idiosoma of a partially engorged female I. angustus that was attached to, and feeding on, an American red squirrel, Tamiasciurus hudsonicus (Erxleben). This hyperparasitic interaction is discussed and illustrated with a Scanning Electron Micrograph.