title: Isolation of Novel Trypanosomatid, Zelonia australiensis sp. nov. (Kinetoplastida: Trypanosomatidae) Provides Support for a Gondwanan Origin of Dixenous Parasitism in the Leishmaniinae.
abstract: The genus Leishmania includes approximately 53 species, 20 of which cause human leishmaniais; a significant albeit neglected tropical disease. Leishmaniasis has afflicted humans for millennia, but how ancient is Leishmania and where did it arise? These questions have been hotly debated for decades and several theories have been proposed. One theory suggests Leishmania originated in the Palearctic, and dispersed to the New World via the Bering land bridge. Others propose that Leishmania evolved in the Neotropics. The Multiple Origins theory suggests that separation of certain Old World and New World species occurred due to the opening of the Atlantic Ocean. Some suggest that the ancestor of the dixenous genera Leishmania, Endotrypanum and Porcisia evolved on Gondwana between 90 and 140 million years ago. In the present study a detailed molecular and morphological characterisation was performed on a novel Australian trypanosomatid following its isolation in Australia's tropics from the native black fly, Simulium (Morops) dycei Colbo, 1976. Phylogenetic analyses were conducted and confirmed this parasite as a sibling to Zelonia costaricensis, a close relative of Leishmania previously isolated from a reduviid bug in Costa Rica. Consequently, this parasite was assigned the name Zelonia australiensis sp. nov. Assuming Z. costaricensis and Z. australiensis diverged when Australia and South America became completely separated, their divergence occurred between 36 and 41 million years ago at least. Using this vicariance event as a calibration point for a phylogenetic time tree, the common ancestor of the dixenous genera Leishmania, Endotrypanum and Porcisia appeared in Gondwana approximately 91 million years ago. Ultimately, this study contributes to our understanding of trypanosomatid diversity, and of Leishmania origins by providing support for a Gondwanan origin of dixenous parasitism in the Leishmaniinae.
authors.affiliation: School of Life Sciences, University of Technology Sydney, Sydney, New South Wales, Australia.
authors.forename: Joel
authors.initials: J
authors.lastname: Barratt
authors.affiliation: School of Life Sciences, University of Technology Sydney, Sydney, New South Wales, Australia.
authors.forename: Alexa
authors.initials: A
authors.lastname: Kaufer
authors.affiliation: School of Life Sciences, University of Technology Sydney, Sydney, New South Wales, Australia.|Insect Research Facility, University of Technology Sydney, Sydney, New South Wales, Australia.
authors.forename: Bryce
authors.initials: B
authors.lastname: Peters
authors.affiliation: Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada.
authors.forename: Douglas
authors.initials: D
authors.lastname: Craig
authors.affiliation: Faculty of Veterinary Science, University of Sydney, Sydney, New South Wales, Australia.|Department of Medical Entomology, University of Sydney & Pathology West - ICPMR, Westmead Hospital, Westmead, New South Wales, Australia.
authors.forename: Andrea
authors.initials: A
authors.lastname: Lawrence
authors.affiliation: St. Vincent's Hospital Sydney, Division of Microbiology, Sydney, New South Wales, Australia.
authors.forename: Tamalee
authors.initials: T
authors.lastname: Roberts
authors.affiliation: Centre for Infectious Diseases and Microbiology Laboratory Services, ICPMR, Westmead Hospital, Westmead, New South Wales, Australia.
authors.forename: Rogan
authors.initials: R
authors.lastname: Lee
authors.affiliation: Microbiology Department, Royal Darwin Hospital, Darwin, Northern Territory, Australia.
authors.forename: Gary
authors.initials: G
authors.lastname: McAuliffe
authors.affiliation: St. Vincent's Hospital Sydney, Division of Microbiology, Sydney, New South Wales, Australia.
authors.forename: Damien
authors.initials: D
authors.lastname: Stark
authors.affiliation: School of Life Sciences, University of Technology Sydney, Sydney, New South Wales, Australia.
authors.forename: John
authors.initials: J
authors.lastname: Ellis
mesh_terms: D000818:Animals; D001315:Australia; D005260:Female; D007303:Insect Vectors / Q000145:classification / Q000469:parasitology*; D007313:Insecta / Q000145:classification / Q000469:parasitology*; D016830:Kinetoplastida / Q000145:classification / Q000235:genetics / Q000302:isolation & purification* / Q000502:physiology*; D007891:Leishmania / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology; D008297:Male; D010802:Phylogeny