Host Associations, Phylogenetics, and Biogeography of Parasitic Avian Chewing Lice (Insecta: Phthiraptera) from Sub-Saharan Africa

Abstract

Parasitic chewing lice (Insecta: Phthiraptera) of birds are found everywhere their avian hosts are distributed, and their host relationships and taxonomy have been well studied in many regions. Lice have obligate parasitic relationships with their hosts (entire life cycle is carried out on the host body) and generally undergo vertical transmission across host generations. These biological traits of lice make them excellent model systems for exploring host-parasite co-evolution. Compared with Europe and the Americas, the ectoparasite fauna of Sub-Saharan African birds is poorly understood despite the avian fauna being relatively well-known. Recent field expeditions exploring the avian diversity in South Africa, Benin, and the Democratic Republic of the Congo allow an opportunity to obtain louse specimens from across Sub-Saharan Africa. The goal of this study was to investigate avian louse host associations and genetic diversity to increase our understanding of southern African parasite biodiversity, as well as to use molecular phylogenetic methods to examine potential broad biogeographic patterns in lice across Sub-Saharan Africa. From 1105 South African bird individuals and 170 species examined for lice, a total of 104 new louse-host associations were observed. Portions of the mitochondrial COI and nuclear EF-1α genes were amplified to observe phylogenetic relationships of southern African lice and investigate potential new species. The phylogenetic results gave strong support for multiple louse genera, and 26 genetically unique lineages were found, which may represent new louse species. Examining biogeographic patterns in parasitic lice across the entire region of Sub-Saharan Africa indicated that lice tend to follow host distributions rather than grouping by geographic region. Several promising louse taxa were identified as candidates for future phylogenetic and biogeographic studies investigating Sub-Saharan African chewing lice.