Molecular analyses on host-seeking black flies (Diptera: Simuliidae) reveal a diverse assemblage of Leucocytozoon (Apicomplexa: Haemospororida) parasites in an alpine ecosystem

Abstract

BackgroundMolecular studies have suggested that the true diversity of Leucocytozoon (Apicomplexa: Haemospororida) species well exceeds the approximately 35 currently described taxa. Further, the degree of host-specificity may vary substantially among lineages. Parasite distribution can be influenced by the ability of the parasite to infect a host, vector preferences for certain avian hosts, or other factors such as microhabitat requirements that increase the probability that vertebrate hosts and vectors are in frequent contact with each other. Whereas most studies of haemosporidians have focused on passerine hosts, sampling vectors in the same habitats may allow the detection of other lineages affecting other hosts.MethodsWe sampled abundant, ornithophilic black flies (Simuliidae) across a variety of sites and habitats in the Colorado Rocky Mountains throughout the summer of 2007. Black flies were screened with PCR using Leucocytozoon-specific primers that amplify a portion of the cytochrome b gene, and the sequences were compared to the haplotypes in the MalAvi database. Infections of Leucocytozoon from birds sampled in the same area were also included.ResultsWe recovered 33 unique haplotypes from the black flies in this study area, which represented a large phylogenetic diversity of Leucocytozoon parasites. However, there were no clear patterns of avian host species or geography for the distribution of Leucocytozoon haplotypes in the phylogeny.ConclusionsSampling host-seeking vectors is a useful way to obtain a wide variety of avian haemosporidian haplotypes from a given area and may prove useful for understanding the global patterns of host, parasite, and vector associations of these ubiquitous and diverse parasites.Electronic supplementary materialThe online version of this article (doi:10.1186/s13071-015-0952-9) contains supplementary material, which is available to authorized users.

An inverse latitudinal gradient in infection probability and phylogenetic diversity for Leucocytozoon blood parasites in New World birds

“…Leucocytozoon parasites within a single species (Murdock, Adler, Frank, & Perkins, 2015), supporting the idea that vectors may play important roles in facilitating transmission of Leucocytozoon infections across distantly related bird species. Furthermore, many parasites and pathogens can infect unrelated host species with similar ecological niches, such as habitat use, nesting behaviour and diet Poulin, 2007).…”

“…However, for multi‐host parasites, such as Leucocytozoon , the parasite host range might be decoupled from vertebrate host phylogenetic signal (Galen, Speer, & Perkins, ), as parasite sharing does not occur necessarily between avian taxa that share a common ancestor, but instead through cross‐species transmission between unrelated host taxa mediated via vectors. Blackflies have been shown to harbour high diversities of Leucocytozoon parasites within a single species (Murdock, Adler, Frank, & Perkins, ), supporting the idea that vectors may play important roles in facilitating transmission of Leucocytozoon infections across distantly related bird species. Furthermore, many parasites and pathogens can infect unrelated host species with similar ecological niches, such as habitat use, nesting behaviour and diet (Clark et al, ; Poulin, ).…”

Blood parasites in vectors reveal a united blackfly community in the upper canopy

“…This approach helped provide new knowledge about the diet of some of the most common European black y species. While most studies typically consider only engorged black ies (but see [7,14]), we succeeded to derive more information on diets from analyses of the presence of Leucocytozoon-lineages, combined with existent knowledge on their typical host groups.…”

“…This corresponds to ndings that other European species of Nevermannia attack thrushes and warblers, while black ies of the S. (N.) vernum group and S. (E.) aureum group are relatively rare at heights under 10 m in spruce and pine forests [9,13,28]. Before this study, feeding preferences of Nevermannia and Eusimulium species were known only from S. (N.) silvestre, S. (N.) curvans, S. (E.) angustipes and S. (E.) aureum, the latter being one of the best examined ornithophilic black ies and vectors of Leucocytozoon [7,11,14,15,28,29]. This species, however, appears to be rather rare in the upper canopy.…”

“…These characteristics of Leucocytozoon evolution may be assisted by the behaviour of black ies [13]. The diversity and specialisation of Leucocytozoon lineages allow them to be used as natural markers for the diet of the respective vectors [14]. Identifying the genetic lineages of Leucocytozoon in black ies can reveal the diet preferences and behaviour of separate vector species, which in turn can contribute to the understanding of Leucocytozoon transmission and evolution [6,15].…”