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Abstract Haemosporidians constitute a monophyletic group of vector-borne parasites that infect a wide range of vertebrate hosts, including Neotropical lizards. The remarkable diversity of these host-parasite associations and inadequate research on certain parasite groups have resulted in controversial haemosporidian taxonomy. Herein, we rediscover erythrocytic and non-erythrocytic haemosporidians infecting golden tegus (Tupinambis teguixin) from Brazil and Colombia. The erythrocyte-inhabiting parasite belongs toPlasmodiumsp., and the non-erythrocytic form was identified asSaurocytozoon tupinambi, previously attributed to the Family Leucocytozoidae. These non-pigmented haemosporidian parasites do not multiply in the blood. The relationships between theSaurocytozoonand Leucocytozoidae species were discussed for many years, especially during the 1970s. However, cytochrome b (cytb) sequences and the mitochondrial genomes recovered for this species strongly support classifying this parasite as aPlasmodiumtaxon. Therefore, we proposed a new combination for this parasite,Plasmodium(Saurocytozoon)tupinambicomb. nov., whereSaurocytozoonis retained as a subgenus due to its distinct morphology. These results reinforce that a broader definition of Plasmodiidae must include saurian parasites that develop non-pigmented leucocytozoid-like gametocytes.
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Global drivers of avian haemosporidian infections vary across zoogeographical regions
Abstract AimMacroecological analyses provide valuable insights into factors that influence how parasites are distributed across space and among hosts. Amid large uncertainties that arise when generalizing from local and regional findings, hierarchical approaches applied to global datasets are required to determine whether drivers of parasite infection patterns vary across scales. We assessed global patterns of haemosporidian infections across a broad diversity of avian host clades and zoogeographical realms to depict hotspots of prevalence and to identify possible underlying drivers. LocationGlobal. Time period1994–2019. Major taxa studiedAvian haemosporidian parasites (generaPlasmodium,Haemoproteus,LeucocytozoonandParahaemoproteus). MethodsWe amalgamated infection data from 53,669 individual birds representing 2,445 species world‐wide. Spatio‐phylogenetic hierarchical Bayesian models were built to disentangle potential landscape, climatic and biotic drivers of infection probability while accounting for spatial context and avian host phylogenetic relationships. ResultsIdiosyncratic responses of the three most common haemosporidian genera to climate, habitat, host relatedness and host ecological traits indicated marked variation in host infection rates from local to global scales. Notably, host ecological drivers, such as migration distance forPlasmodiumandParahaemoproteus, exhibited predominantly varying or even opposite effects on infection rates across regions, whereas climatic effects on infection rates were more consistent across realms. Moreover, infections in some low‐prevalence realms were disproportionately concentrated in a few local hotspots, suggesting that regional‐scale variation in habitat and microclimate might influence transmission, in addition to global drivers. Main conclusionsOur hierarchical global analysis supports regional‐scale findings showing the synergistic effects of landscape, climate and host ecological traits on parasite transmission for a cosmopolitan and diverse group of avian parasites. Our results underscore the need to account for such interactions, in addition to possible variation in drivers across regions, to produce the robust inference required to predict changes in infection risk under future scenarios.
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- Award ID(s):
- 2001213
- PAR ID:
- 10360093
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Global Ecology and Biogeography
- Volume:
- 30
- Issue:
- 12
- ISSN:
- 1466-822X
- Page Range / eLocation ID:
- p. 2393-2406
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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