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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 March 1, 2026
A severe head louse ( Pediculus humanus capitis ) infestation: Timeline, pathogen detection, kdr ‐gene screening and morphological anomalies of lice
Abstract Lice are assuming an increasing importance in forensic investigations, given their capacity to provide information about an individual's care. Head louse pediculosis is a frequent condition in school‐age children and can be properly controlled using topical treatments combined with good personal hygiene. Prolonged and chronic infestations may result in more serious outcomes including severe iron deficiency anaemia. We conducted entomological and laboratory investigations of a head louse infestation in a 12‐year‐old girl who experienced severe anaemia and subsequent death. Numerous lice were found postmortem on the head, face and neck of the patient, as well as on bedding and clothing. Analysis of nits on individual hairs determined that the louse infestation had been present for at least 166 days. The lice had some morphological traits characteristic of body lice: the third antennal segment in some specimens was distinctly longer than wide, and the apices of some paratergal plates did not extend into intersegmental membranes, while other morphological features were characteristic of head or body lice. All lice were heterozygous for the T917Ikdrgenotype, a marker of permethrin resistance. Nineteen (79.2%, 95%CI 59.5%–90.8%) louse DNA samples tested TaqMan positive forAcinetobacter(Moraxellales; Moraxellaceae) sp. Available information and laboratory findings are further discussed regarding their possible contribution to the negative outcome of this case. We stress the impact head louse pediculosis can have on children with limited parental attention, and how severe head louse infestation may serve as warning sign of neglect, and other high‐risk situations.
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- PAR ID:
- 10631446
- Publisher / Repository:
- Medical and Veterinary Entomology
- Date Published:
- Journal Name:
- Medical and Veterinary Entomology
- Volume:
- 39
- Issue:
- 1
- ISSN:
- 0269-283X
- Page Range / eLocation ID:
- 69 to 77
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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