Explore the vast range of titles available.

Many parasitic insects, including lice, form close relationships with endosymbiotic bacteria that are crucial for their survival. In this study, we used genomic sequencing to investigate the distribution and evolutionary history of the bacterial genus Sodalis across a broad range of feather louse species spanning 140 genera. Phylogenomic analysis revealed significant diversity among Sodalis lineages in feather lice and robust evidence for their independent and repeated acquisition by different louse clades throughout their radiation. Among the 1020 louse genomes analysed, at least 22% contained Sodalis, distributed across 57 louse genera. Cophylogenetic analyses between the Sodalis and feather louse phylogenies indicated considerable mismatch. This phylogenetic incongruence between lice and Sodalis, along with the presence of distantly related Sodalis lineages in otherwise closely related louse species, strongly indicates repeated independent acquisition of this endosymbiont. Additionally, evidence of cospeciation among a few closely related louse species, coupled with frequent acquisition of these endosymbionts from free-living bacteria, further highlights the diverse evolutionary processes shaping Sodalis endosymbiosis in feather lice.

South Texas is a highly variable region encompassing multiple habitat types and harboring a wide diversity of organisms. However, the parasite fauna in this region is poorly known, especially for avian ectoparasites such as lice. To better understand avian louse diversity and host associations in South Texas, we examined a total of 507 birds for chewing lice. Lice were morphologically identified to genus and phylogenetic analysis was performed using one mitochondrial (COI) and two nuclear (18S rRNA and EF-1α) genes. Of the birds examined, 69 (13.5%) were parasitized by lice resulting in a total of 63 host associations across 45 bird species, 29 of which were previously unrecorded. The predominant taxa encountered during this study included two of the most diverse louse genera, Myrsidea and Brueelia. Molecular analyses revealed 21 distinct genetic lineages, 17 of which are associated with novel host associations and may represent new species. This study represents the first extensive examination of avian louse host associations and relationships in Texas and reveals that there is still much to be learned about ectoparasite diversity in the New World.

Background As living vectors, arthropods play a crucial role in the transmission of viruses, bacteria and parasites. Previous research on virus transmission has focussed mainly on the roles of mosquitoes and ticks, while the potential importance of other blood-sucking arthropods such as louse flies (Hippoboscidae) has been somewhat neglected. The aim of this study was to detect viruses in avian louse flies from Germany to assess whether they could be used as sentinel organisms for monitoring arboviruses with zoonotic potential. Methods We collected 1000 louse flies of the species Crataerina hirundinis, C. pallida, Ornithomya avicularia, O. biloba, O. fringillina, O. chloropus, Ornithophila metallica and Pseudolynchia canariensis in Germany and screened the samples via RT-PCR for West Nile virus (WNV), Usutu virus (USUV) and Sindbis virus (SINV), which are arboviruses with avian hosts as reservoirs. Results While WNV was not detected, we found one louse fly positive for USUV and one for SINV RNA, both of which belonged to the species O. avicularia ( n  = 279). Therefore, the detection rates for both USUV and SINV were 0.1% (95% CI 0.0–0.3%) in the total sample and 0.36% (95% CI 0.00–1.09%) in O. avicularia . For the sample that tested positive for SINV, the PCR results were confirmed by sequencing a 288-bp segment that encoded part of the virus’s structural polyprotein. Conclusions This is the first time that USUV RNA and SINV RNA have been detected in louse flies. In addition, it is the first detection of human pathogenic viruses in the louse fly species O. avicularia . The results of this study indicate that louse flies should not be neglected as possible sentinels of viral pathogens with zoonotic potential in the sense of the One Health concept. Graphical abstract

The morphological features of three instars of nymphs and adults of Columbicola bacillus (Ischnocera: Phthiraptera) collected from Collard-dove Streptopelia decaocto were studied. Present report furnishes  Second instar nymph can be separated from first instar due to appearance of additional seta on pterothorax on seventh to eight adominal segments. Third instars can be distinguished from second instar due to appearance of pleural seta on abdominal segment seventh to ninth.

Avian lice occupy different habitats in the host plumage that the physical environment outside the host body may affect in several ways. Interactions between host plumage and water may be an important source of such effects. Here, we use a comparative approach to examine the effect of a host's diving behavior on the taxonomic richness of its lice. Louse genera richness was significantly lower in clades of diving birds than on their nondiving sister clades. Species richness of host and body mass did not differ significantly between these clades; thus, these factors did not bias our results. This study suggests that the hosts' diving behavior can effectively influence ectoparasite communities.

Ornitho-parasitological studies in Türkiye began in the early 2000s, focusing on chewing lice, and have continued to increase to the present day – new studies, records, and host-parasite associations – are published each year. Despite this progress, the chewing lice fauna of many wild bird species in Türkiye remains poorly known, especially among raptor species (Accipitriformes and Falconiformes). Faunistic records of birds of prey are still limited, and each novel record or novel host-parasite association provides valuable data for understanding host specificity and ectoparasite distribution. The material of this study consists of chewing lice specimens collected from the Lesser Spotted Eagle and were mounted on slides using standard clearing and mounting techniques and examined under a light microscope for identification. As a result, the specimens were identified as Rudow, 1866, (Giebel, 1861), (Giebel, 1874), and (Rudow, 1869). Among these species, represents a new record for the chewing lice fauna of Türkiye. This study contributes to the understanding the ectoparasite biodiversity of birds of prey in Türkiye and emphasises the importance of continued parasitological studies of wild avian species.

Lice were collected from 579 hummingbirds, representing 49 species, in 19 locations in Brazil, Costa Rica, Honduras, Paraguay and Peru, at elevations 0–3000 m above sea level. The following variables were included in an ecological analysis (1) host species' mean body mass, sexual size dimorphism, sexual dichromatism, migratory behaviour and dominance behaviour; (2) mean elevation, mean and predictability of temperature, mean and predictability of precipitation of the host species' geographic area; (3) prevalence and mean abundance of species of lice as measures of infestation. Ordination methods were applied to evaluate data structure. Since the traits are expressed at different scales (nominal, interval and ratio), a principal component analysis based on d-correlations for the traits and a principal coordinates analysis based on the Gower index for species were applied. Lice or louse eggs were found on 80 (13.8%) birds of 22 species. A total of 267 lice of 4 genera, Trochiloecetes, Trochiliphagus, Myrsidea and Leremenopon, were collected, with a total mean intensity of 4.6. There were positive interactions between migration behaviour and infestation indices, with elevational migrants having a higher prevalence and abundance of lice than resident birds. Further, we found weak negative correlations between host body mass and infestation indices and positive correlations between mean elevation and prevalence and abundance of Trochiliphagus. Thus, formerly unknown differences in the ecological characteristics and infestation measures of Trochiliphagus and Trochiloecetes lice were revealed, which allows a better understanding of these associations and their potential impacts on hummingbirds.

Chewing lice (Phthiraptera, Ischnocera and Amblycera) are permanent ectoparasites of birds and primarly feed on the feathers and scales of birds. To detect the chewing lice species found on birds in Aras basin, Igdir, Türkiye, a total of 240 birds represented by 61 species belonging to 30 families in 13 orders were examined during the 2021 bird migration season. A total of 531 (186 females, 136 males and 209 nymphs) lice were collected from 75 individuals (31,25% of birds examined) of 26 species, 21 families and 10 orders. Thirty-one lice species (11 amblyceran and 20 ischnoceran species) in 22 genera were identified. Of these, 15 lice species were reported for the first time in Türkiye, namely Cuculiphilus fasciatus , Pseudomenopon qadrii , Philopterus sp., Ricinus serratus , Philopterus picae , Rostrinirmus buresi , Sturnidoecus sp . , Philopterus excisus , Philopterus microsomaticus , Philopterus coarctatus , Brueelia fuscopleura , Sturnidoecus pastoris , Brueelia currucae , Penenirmus auritus and Strigiphilus tuleskovi . In addition, new host associations were reported for the lice species Kurodaia fulvofasciata , Degeeriella rufa and Myrsidea rustica .

Borreliae of the relapsing fever group (RFG) are heterogenous and can be divided mainly into three groups according to vectors, namely the soft-tick-borne relapsing fever (STBRF) Borreliae, the hard-tick-borne relapsing fever (HTBRF) Borreliae, the louse-borne relapsing fever (LBRF) Borreliae, and the avian relapsing fever ones. With respect to the geographical distribution, the STBRF Borreliae are further subdivided into Old World and New World strains. Except for the Avian relapsing fever group Borreliae, which cause avian spirochetosis, all the others share infectivity in humans. They are indeed the etiological agent of both endemic and epidemic forms of relapsing fever, causing high spirochaetemia and fever. Vectors are primarily soft ticks of Ornithodoros spp. in the STBRF group; hard ticks, notably Ixodes sp., Amblyomma sp., Dermacentor sp., and Rhipicephalus sp., in the HTBRF group; and the louse pediculus humanus humanus in the TBRF one. A recent hypothesis was supported for a common ancestor of RFG Borreliae, transmitted at the beginning by hard-body ticks. Accordingly, STBRF Borreliae switched to use soft-bodied ticks as a vector, which was followed by the use of lice by Borrelia recurrentis. There are also new candidate species of Borreliae, at present unclassified, which are also described in this review.

Studies of biodiversity traditionally focus on charismatic megafauna. By comparison, little is known about parasite biodiversity. Recent studies suggest that co-extinction of host specific parasites with their hosts should be common and that parasites may even go extinct before their hosts. The few studies examining the relationship between parasite diversity and habitat quality have focused on parasites that require intermediate hosts and pathogens that require vectors to complete their life-cycles. Declines in parasite and pathogen richness in these systems could be due to the decline of any of the definitive hosts, intermediate hosts, or vectors. Here we focus on avian ectoparasites, primarily lice, which are host specific parasites with simple, direct, life-cycles. By focusing on these parasites we gain a clearer understanding of how parasites are linked to their hosts and their hosts’ environment. We compare parasite richness on birds from fragmented forests in southern China. We show that parasite richness correlates with forest size, even among birds that are locally common. The absence of some ectoparasite genera in small forests suggests that parasites can go locally extinct even if their hosts persist. Our data suggest that the conservation of parasite biodiversity may require preservation of habitat fragments that are sufficiently large to maintain parasite populations, not just their host populations.