A total of 114 individuals of 14 wren species (Aves: Passeriformes: Troglodytidae) were examined. Nineteen birds (17 %) of six species were parasitised with 292 chewing lice (mean intensity = 15.4 lice per bird) belonging to three genera - Brueelia Kéler, 1936, Penenirmus Clay & Meinertzhagen, 1938 (Ischnocera: Philopteridae) and Myrsidea Waterston, 1915 (Amblycera: Menoponidae). Data on the occurrence of chewing lice on wrens, including geographical distributions and some parasitological parameters - such as prevalence and mean intensity - are updated and discussed. A description and illustrations are given for Myrsidea fasciata sp. nov. from Campylorhynchus fasciatus (Swainson, 1837) from Costa Rica. Penenirmus albiventris (Scopoli, 1763) is redescribed from Troglodytes troglodytes (Linnaeus, 1758) (from the Czech Republic and Slovakia) and from T. aedon Vieillot, 1809 (from Peru). Intraspecific morphological variation of P. albiventris is discussed, and detailed figures are given. A portion of the mitochondrial cytochrome oxidase I (COI) gene was sequenced from some species of Myrsidea and Penenirmus in order to assess their relative genetic divergence. An updated list of all species of lice recorded from wrens, including their geographic distribution, and a host-louse list are also given.