Phylogenetics and host‐specificity of the mega‐diverse louse genus Myrsidea (Amblycera: Menoponidae)

Abstract

Myrsidea Waterston is the most diverse genus of chewing lice, primarily parasitizing perching birds (Passeriformes), which is the most speciose avian order. Myrsidea also parasitize several hosts from non-passerine groups, including toucans, barbets, woodpeckers (Piciformes) and hummingbirds (Apodiformes). To examine host specificity, host switching and generic limits, we reconstructed a phylogeny of the avian feather louse genus Myrsidea using DNA sequence data from two fragments of the mitochondrial COI gene and a fragment of the nuclear EF-1α gene for 152 Myrsidea specimens collected from 23 avian host families. Unlike other highly diverse louse genera, only a small proportion of Myrsidea species parasitize more than one host species. We found that host family has significant phylogenetic signal on the Myrsidea phylogeny. These results suggest that Myrsidea is generally highly host-specific, with some exceptions where host switching is important. We found that there are two separate groups of Myrsidea that parasitize toucans, and that both are nested within Myrsidea found on perching birds, suggesting that these toucan ectoparasites may have arisen from two independent host switching events. Lastly, representatives of the genus Ramphasticola Carriker, which was originally described as a distinct genus due to a suite of morphologically unique characters, falls in with a strongly supported clade of Myrsidea parasitizing Ramphastos toucans, and therefore we definitively place Ramphasticola as a synonym of Myrsidea.

Prevalence and diversity of parasitic bird lice (Insecta: Psocodea) in northeast Arkansas

“…The majority of these individuals were collected from Passeriformes, the most common group of birds in our sample ( Table 1 ). We expected Myrsidea and Brueelia to be present on many passeriform species because both are well-known to be associated with songbirds ( Price et al, 2003 ; Bush et al, 2016 , Kolencik et al, 2022 ). These two genera have received relatively considerable attention due to their high species diversity and associations with a diverse group of host species ( Vas et al, 2008 ; Bush et al, 2016 ; Madrid et al, 2020 ; Kolencik et al, 2022 ).…”

“…In addition to our novel sequences, we included existing sequences of cox1 and EF1- α from Brueelia (18 samples from Bush et al, (2016) and Sweet et al, (2018) ) and Myrsidea (18 samples from Kolencik et al, (2022) ) from GenBank ( Table S2 ). We also included sequences of outgroup taxa to root our phylogenetic trees: Theresiella sp.…”

“…from Chimney swift ( Chaetura pelagica ) for Myrsidea ( Table S2 ). We chose the outgroups to be consistent with previous phylogenetic studies of Brueelia and Myrsidea ( Bush et al, 2016 ; Kolencik et al, 2022 ). For each genus, we aligned each gene using MAFFT (v.7.471) with the automatic parameter and checked the sequences manually using Seaview (v.5.0.5) ( Gouy et al, 2010 ).…”