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Abstract Avian feather lice (Phthiraptera: Ischnocera) have undergone morphological diversification into ecomorphs based on how they escape host preening defences. Parrot lice are one prominent example of this phenomenon, with wing, body, or head louse ecomorphs occurring on various groups of parrots. Currently defined genera of parrot lice typically correspond to this ecomorphological variation. Here we explore the phylogenetic relationships among parrot feather lice by sequencing whole genomes and assembling a target set of 2395 nuclear protein coding genes. Phylogenetic trees based on concatenated and coalescent analyses of these data reveal highly supported trees with strong agreement between methods of analysis. These trees reveal that parrot feather lice fall into two separate clades that form a grade with respect to the Brueelia-complex. All parrot louse genera sampled by more than one species were recovered as monophyletic. The evolutionary relationships among these lice showed evidence of strong biogeographic signal, which may also be related to the relationships among their hosts.
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This content will become publicly available on September 1, 2026
Independent and repeated acquisition of Sodalis endosymbiotic bacteria across the diversification of feather lice
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 genusSodalisacross a broad range of feather louse species spanning 140 genera. Phylogenomic analysis revealed significant diversity amongSodalislineages 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% containedSodalis, distributed across 57 louse genera. Cophylogenetic analyses between theSodalisand feather louse phylogenies indicated considerable mismatch. This phylogenetic incongruence between lice andSodalis, along with the presence of distantly relatedSodalislineages 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 shapingSodalisendosymbiosis in feather lice.
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- PAR ID:
- 10645504
- Publisher / Repository:
- The Royal Society Publishing
- Date Published:
- Journal Name:
- Royal Society Open Science
- Volume:
- 12
- Issue:
- 9
- ISSN:
- 2054-5703
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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