A morphological phylogeny with a taxonomic revision of African species of Goniodes (Insecta: Phthiraptera: Ischnocera) sensu lato from the Galliformes (Aves)

Abstract

Parasites are the most diverse metazoan group on earth and are important in understanding ecological and evolutionary processes. Given their high host specificity, simple life cycle and distinctive molecular evolution, the approximately 5000 species of ectoparasitic lice in the order Phthiraptera are ideal models for such work. Unfortunately, study of this group is hindered by a history of poor taxonomy and a lack of a widely accepted higher-level phylogeny for the Phthiraptera. This study broadly contributes to our understanding of the suborder Ischnocera, and more specifically the family Goniodidae. Chapter 1 is a description of Picicola donwebbi, a new species of chewing louse from the Rufous-sided Broadbill (Smithornis rufolateralis Gray, 1864) from Ghana. It is the first species of Ischnocera recorded from broadbills (Passeriformes: Eurylaimidae) and, based on morphology, is placed in the Picicola quadripustulosus species group recorded from the Pittidae (Passeriformes). To evaluate its genetic distinctiveness and phylogenetic position in the Degeeriella complex sequences of nuclear (elongation factor-1) and mitochondrial (cytochrome oxidase I) genes for this species are compared to that of various other species. Although P. donwebbi is genetically distinct its phylogenetic position within the larger complex remains unclear. Chapter 2 consists of the first phylogenetic analysis of the basal ischnoceran genus Goniodes based on morphological data. The analysis includes 36 species of Goniodes representing all 13 recognized intrageneric groups, as well as 9 taxa representing 4 additional ischnoceran genera: Goniocotes (6 species), Physconelloides (1 species), Campanulotes (1 species), and Heptapsogaster (1 species) as outgroups. The parsimony analysis of 262 morphological characters found 5 most parsimonious trees with a length of 2486 steps (CI: 0.276; RI: 0.561; RC: 0.150). A consensus is mostly resolved with the exception of disagreement between two weakly supported basal groups containing a single species of Goniodes and species of the genus Goniocotes. The overall tree topology, characterized by a continuous stepwise branching pattern, is largely a grade with the placement of taxa strongly correlated with general size. Clay’s subgeneric classification, although not fully substantiated, is largely confirmed. However, it largely confirms broad relationships, showing that smaller, medium, and large-bodied species cluster together. Even so, monophyletic and strongly supported apical groups cannot from a gross taxonomic perspective be effectively “described/circumscribed” in light of morphology alone. It is thus apparent that the reality of the biological complexities associated with ubiquitous morphological convergence in the Ischnocera at large, and Goniodes specifically, cannot effectively be separated from the artificial intricacies imposed by classification. Chapter 3 reviews the African species of Goniodes placing 31 species in 8 intrageneric groups following Clay’s revision. An additional 5 species from 3 intrageneric groups that are incidental or introduced to Africa are also briefly discussed. This chapter provides an extensive review of the taxonomic and nomenclatural histories, host associations of each species, and concludes with an discussion of the current status of each species. The intrageneric groups, including the component species with their type hosts are: Group F – G. wilsoni ex Afropavo congensis; Group G – G. numidae ex Numida m. meleagris, G. hopkinsi ex Guttera edouardi seth-smithi, G. meyi ex Numida meleagris meleagris, G. klockenhoffi ex Numida meleagris reichenowi, G. reichenowii ex Numida meleagris reichenowi, G. plumiferae ex Guttera plumifera schubotzi, G. schoutedenii ex Guttera edouardi verreauxi, G. inaequalis ex Guttera edouardi barbata; Group H – G. gigas ex Gallus gallus, G. agelastes ex Agelastes meleagrides, G. bifurcus ex Guttera pucherani pucherani, G. zairensis ex Guttera plumifera schubotzi, G. gutterae ex Guttera plumifera plumifera, G. phasidus ex Phasidus niger; Group I – G. emersoni ex Francolinus psilolaemus; Group K – G. assimilis ex Francolinus capensis, G. ammoperdix ex Ammoperdix griseogularis, G. antennatus ex Francolinus leucoscepus leucoscepus, G. oreophilus ex Francolinus psilolaemus elgonensis, G. scleroptilus ex Francolinus levaillantoides jugularis, G. isogenos ex Francolinus africanus africanus, Group L – G. soueefi ex Coturnix chinensis australis, G. astrocephalus ex Coturnix coturnix coturnix, G. moucheti ex Francolinus nobilis, G. lootensi ex Coturnix chinensis adansonii. Species introduced or incidental to Sub-Saharan Africa includes: Group A – G. pavonis introduced via its type host Pavo cristatus; Group B – G. meinertzhagenii introduced via its type host Pavo cristatus; Group K – G. dispar introduced via its type host Perdix perdix (Perdix cinerea) to Robben Island, South Africa, and also known from single specimen collected from zoo specimen of Francolinus afer cranchii in Zimbabwe, G. securiger incidental in Sub-Saharan Africa via its type host Alectoris barbara barbara, G. dissimilis ex Gallus gallus incidental in Sub-Saharan Africa via domestic chickens. Chapter 4 in keeping with the recommendations of the International Code of Zoological Nomenclature is the first published listing of the Phthirapteran (Insecta) type material housed in the Royal Museum for Central Africa in Tervuren, Belgium. This annotated catalogue lists the primary and secondary types of 63 chewing lice taxa from the suborder Amblycera (families Menoponidae and Laemobothriidae) and Ischnocera (families Philopteridae and Trichodectidae), and includes data for 39 holotypes, 488 paratypes (including 23 allotypes), 7 metatypes, and 34 “type” specimens of unknown status. Relevant taxa are listed alphabetically by specific epithet, original generic assignment, and (in parentheses) the current family designation. Also included are the author, year of description, and original citation, followed by the type, original collection and host data, any relevant taxonomic remarks, and its current taxonomic status. Appendix A, is a collaborative study investigating a major host switches in the Goniodidae. Such host switches by parasites between highly divergent host lineages are important for understanding new opportunities for parasite diversification. One such major host switch is inferred for avian feather lice (Ischnocera) in the family Goniodidae, which parasitize two distantly related groups of birds: Galliformes (pheasants, quail, partridges, etc.) and Columbiformes (pigeons and doves). Although there have been several cophylogenetic studies of lice at the species level, few studies have focused on such broad evolutionary patterns and major host-switching events. Using a phylogeny based on DNA sequences for goniodid feather lice, we investigated the direction of this major host switch. Surprisingly, we found that goniodid feather lice have switched host orders, not just once, but twice. A primary host switch occurred from Galliformes to Columbiformes, leading to a large radiation of columbiform body lice. Subsequently, there was also a host switch from Columbiformes back to Galliformes, specifically to megapodes in the Papua-Australasian region. Our results further reveal that although morphologically diagnosable lineages are supported by molecular data, many of the existing genera are not monophyletic and a revision of generic limits is needed