New avian hosts for Taphropiestes plaumanni (Coleoptera: Cavognathidae) and the record of nestlings skin lesions and body deterioration associated with parasitism.

We collected data during three consecutive breeding seasons (2015-2018) to assess the effects of Taphropiestes plaumanni (Coleoptera: Cavognathidae) on its bird hosts in a native forest of central eastern Argentina. We monitored bird nests for T. plaumanni in 207 nests of Masked Gnatcatcher (Polioptila dumicola, Polioptilidae), 302 nests of Vermilion Flycatcher (Pyrocephalus rubinus, Tyrannidae), 55 nests of Blue-and-yellow Tanager (Pipraeidea bonariensis, Thraupidae), 99 nests of Small-billed Elaenia (Elaenia parvirostris, Tyrannidae), 23 nests of Yellow-browed Tyrant (Satrapa icterophrys, Tyrannidae), and other passerine species nesting in the same forest patches. We found 13 nests in which nestlings showed evidences of parasitism of which four species are new hosts for this parasite (Vermilion Flycatcher, Masked Gnatcatcher, Red-crested Cardinal Paroaria coronata, Thraupidae, and Fork-tailed Flycatcher Tyrannus savana). Skin lesions caused by T. plaumanni larvae consisted in lacerations and crusts on the belly and chest areas. In one parasitized nest of Vermilion Flycatcher and one parasitized nest of Masked Gnatcatcher we observed the death of nestlings after being parasitized. This study adds new species to the list of hosts for this parasite, reports nestling skin lesions in nests with T. plaumanni parasitism, and reports for the first time the death of parasitized nestlings.