Shared species of crocodilian trypanosomes carried by tabanid flies in Africa and South America, including the description of a new species from caimans, Trypanosoma kaiowa n. sp.

Parasites & Vectors

Desie Sheferaw¹  Fernando Paiva²  Carlos A. G. S. Jared³  John J. Kisakye⁴  Agapitus Kato⁵  Herakles A. Garcia⁶  Carmen S. A. Takata⁶  Marta Campaner⁶  Bruno R. Fermino⁶  Carla M. F. Rodrigues⁷  Marta M. G. Teixeira⁷  Erney P. Camargo⁷  Laerte B. Viola⁸ 

[1] 0000 0000 8953 2273, grid.192268.6, Department of Veterinary Medicine, Hawassa University, Hawassa, Ethiopia;0000 0001 2163 5978, grid.412352.3, Biological Institute, Federal University of Mato Grosso do Sul, Campo Grande, Mato Grosso do Sul, Brazil;0000 0004 0615 8175, grid.419716.c, Instituto Butantan, Secretaria da Saúde, São Paulo, Brazil;0000 0004 0620 0548, grid.11194.3c, Department of Zoology, Entomology and Fisheries Sciences, Makerere University, Kampala, Uganda;0000 0004 0620 0548, grid.11194.3c, Department of Zoology, Entomology and Fisheries Sciences, Makerere University, Kampala, Uganda;0000 0004 1790 6116, grid.415861.f, Uganda Virus Research Institute, Entebbe, Uganda;0000 0004 1937 0722, grid.11899.38, Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil;0000 0004 1937 0722, grid.11899.38, Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil;Instituto Nacional de Ciência e Tecnologia, EpiAmo, Porto Velho, Rondônia, Brazil;Department of Environment, Arcadis, São Paulo, Brazil;

关键词: Tabanids;    Tsetse flies;    Crocodile;    Caiman;    Evolution;    Taxonomy;    Morphology;    Transoceanic dispersal;   

DOI  :  10.1186/s13071-019-3463-2

来源: publisher

【 摘 要 】

BackgroundThe genus Trypanosoma Gruby, 1843 is constituted by terrestrial and aquatic phylogenetic lineages both harboring understudied trypanosomes from reptiles including an increasing diversity of crocodilian trypanosomes. Trypanosoma clandestinus Teixeira & Camargo, 2016 of the aquatic lineage is transmitted by leeches to caimans. Trypanosoma grayi Novy, 1906 of the terrestrial lineage is transmitted by tsetse flies to crocodiles in Africa, but the vectors of Neotropical caiman trypanosomes nested in this lineage remain unknown.ResultsOur phylogenetic analyses uncovered crocodilian trypanosomes in tabanids from South America and Africa, and trypanosomes other than T. grayi in tsetse flies. All trypanosomes found in tabanids clustered in the crocodilian clade (terrestrial lineage) forming six clades: Grayi (African trypanosomes from crocodiles and tsetse flies); Ralphi (trypanosomes from caimans, African and Brazilian tabanids and tsetse flies); Terena (caimans); Cay03 (caimans and Brazilian tabanids); and two new clades, Tab01 (Brazilian tabanid and tsetse flies) and Kaiowa. The clade Kaiowa comprises Trypanosoma kaiowa n. sp. and trypanosomes from African and Brazilian tabanids, caimans, tsetse flies and the African dwarf crocodile. Trypanosoma kaiowa n. sp. heavily colonises tabanid guts and differs remarkably in morphology from other caiman trypanosomes. This species multiplied predominantly as promastigotes on log-phase cultures showing scarce epimastigotes and exhibited very long flagellates in old cultures. Analyses of growth behavior revealed that insect cells allow the intracellular development of Trypanosoma kaiowa n. sp.ConclusionsPrior to this description of Trypanosoma kaiowa n. sp., no crocodilian trypanosome parasitic in tabanid flies had been cultured, morphologically examined by light, scanning and transmission microscopy, and phylogenetically compared with other crocodilian trypanosomes. Additionally, trypanosomes thought to be restricted to caimans were identified in Brazilian and African tabanids, tsetse flies and the dwarf crocodile. Similar repertoires of trypanosomes found in South American caimans, African crocodiles and tabanids from both continents support the recent diversification of these transcontinental trypanosomes. Our findings are consistent with trypanosome host-switching likely mediated by tabanid flies between caimans and transoceanic migrant crocodiles co-inhabiting South American wetlands at the Miocene.

【 授权许可】

CC BY