Skip to main content
    • Aa
    • Aa

Trypanosoma irwini n. sp (Sarcomastigophora: Trypanosomatidae) from the koala (Phascolarctos cinereus)

  • L. M. McINNES (a1), A. GILLETT (a2), U. M. RYAN (a1), J. AUSTEN (a1), R. S. F. CAMPBELL (a3), J. HANGER (a2) and S. A. REID (a1)...

The morphology and genetic characterization of a new species of trypanosome infecting koalas (Phascolarctos cinereus) are described. Morphological analysis of bloodstream forms and phylogenetic analysis at the 18S rDNA and gGAPDH loci demonstrated this trypanosome species to be genetically distinct and most similar to Trypanosoma bennetti, an avian trypanosome with a genetic distance of 0·9% at the 18S rDNA and 10·7% at the gGAPDH locus. The trypanosome was detected by 18S rDNA PCR in the blood samples of 26 out of 68 (38·2%) koalas studied. The aetiological role of trypanosomes in koala disease is currently poorly defined, although infection with these parasites has been associated with severe clinical signs in a number of koalas. Based on biological and genetic characterization data, this trypanosome species infecting koalas is proposed to be a new species Trypanosome irwini n. sp.

Corresponding author
*Corresponding author: Division of Health Sciences, School of Veterinary and Biomedical Sciences, Murdoch University, Murdoch, Perth6150, Western Australia. Tel: +61 893 602495. Fax: +61 893 104144. E-mail:
Linked references
Hide All

This list contains references from the content that can be linked to their source. For a full set of references and notes please see the PDF or HTML where available.

M. Anisimova and O. Gascuel (2006). Approximate likelihood-ratio test for branches: A fast, accurate, and powerful alternative. Systematic Biology 55, 539552.

S. S. Bettiol , J. M. Goldsmid , D. D. Le and M. Driessen (1996). The first record of a member of the genus Hepatozoon in the eastern barred bandicoot (Perameles gunnii) in Tasmania. Journal of Parasitology 82, 829830.

S. S. Bettiol , K. Jakes , D. D. Le , J. M. Goldsmid and G. Hocking (1998). First record of trypanosomes in Tasmanian bandicoots. Journal of Parasitology 84, 538541.

A. P. Dargantes , R. S. F. Campbell , D. B. Copeman and S. A. Reid (2005). Experimental Trypanosoma evansi infection in the goat. II. Pathology. Journal of Comparative Pathology 133, 267276.

A. Dereeper , V. Guignon , G. Blanc , S. Audic , S. Buffet , F. Chevenet , J. F. Dufayard , S. Guindon , V. Lefort , M. Lescot , J. M. Claverie and O. Gascuel (2008). robust phylogenetic analysis for the non-specialist. Nucleic Acids Research 36, W465–469.

P. B. Hamilton , W. C. Gibson and J. R. Stevens (2007). Patterns of co-evolution between trypanosomes and their hosts deduced from ribosomal RNA and protein-coding gene phylogenies. Molecular and Phylogenetic Evolution 44, 1525.

P. B. Hamilton , J. R. Stevens , M. W. Gaunt , J. Gidley and W. C. Gibson (2004). Trypanosomes are monophyletic: evidence from genes for glyceraldehyde phosphate dehydrogenase and small subunit ribosomal RNA. International Journal for Parasitology 34, 13931404.

P. B. Hamilton , J. R. Stevens , J. Gidley , P. Holz and W. C. Gibson (2005). A new lineage of trypanosomes from Australian vertebrates and terrestrial bloodsucking leeches (Haemadipsidae). International Journal for Parasitology 35, 431443.

J. J. Hanger , L. D. Bromham , J. J. McKee , T. M. O'brien and W. F. Robinson (2000). The nucleotide sequence of koala (Phascolarctos cinereus) retrovirus: a novel type C endogenous virus related to Gibbon ape leukemia virus. Journal of Virolology 74, 42644272.

S. Hatama , T. Shibahara , M. Suzuki , K. Kadota , I. Uchida and T. Kanno (2007). Isolation of a Megatrypanum trypanosome from sika deer (Cervus nippon yesoensis) in Japan. Veterinary Parasitology 149, 5664.

C. E. Kirkpatrick and C. A. Terway-Thompson (1986). Biochemical characterization of some raptor trypanosomes. II. Enzyme studies, with a description of Trypanosoma bennetti n. sp. Canadian Journal of Zoology 64, 195203.

A. A. Latif , M. A. Bakheit , A. E. Mohamed and E. Zweygarth (2004). High infection rates of the tick Hyalomma anatolicum anatolicum with Trypanosoma theileri. Onderstepoort Journal of Veterinary Research 71, 251256.

M. Mackerras (1959). The haematozoa of Australian mammals. Australian Journal of Zoology 7, 105135.

M. Mackerras and I. Mackerras (1960). The haematozoa of Australian birds. Australian Journal of Zoology 8, 226260.

D. A. Maslov , J. Lukes , M. Jirku and L. Simpson (1996). Phylogeny of trypanosomes as inferred from the small and large subunit rRNAs: Implications for the evolution of parasitism in the trypanosomatid protozoa. Molecular and Biochemical Parasitology 75, 197205.

B. McMillan and B. Bancroft (1974). On the morphology of Trypanosoma binneyi Mackerras, 1959 from the platypus Ornithorhyncus anatinus. International Journal for Parasitology 4, 441442.

H. A. Noyes , J. R. Stevens , M. Teixeira , J. Phelan and P. Holz (1999). A nested PCR for the ssrRNA gene detects Trypanosoma binneyi in the platypus and Trypanosoma sp. in wombats and kangaroos in Australia. International Journal for Parasitology 29, 331339.

M. J. Osborne , L. Christidis and J. A. Norman (2002). Molecular phylogenetics of the Diprotodontia (kangaroos, wombats, koala, possums, and allies). Molecular Phylogenetics and Evolution 25, 219228.

H. Sato , N. Leo , Y. Katakai , J. I. Takano , H. Akari , S. I. Nakamura and Y. Une (2008). Prevalence and molecular phylogenetic characterization of Trypanosoma (Megatrypanum) minasense in the peripheral blood of small neotropical primates after a quarantine period. Journal of Parasitology 94, 11281138.

R. N. Sehgal , H. I. Jones and T. B. Smith (2001). Host specificity and incidence of Trypanosoma in some African rainforest birds: a molecular approach. Molecular Ecology 10, 23192327.

A. Smith , P. Clark , S. Averis , A. J. Lymbery , A. F. Wayne , K. D. Morris and R. C. Thompson (2008). Trypanosomes in a declining species of threatened Australian marsupial, the brush-tailed bettong Bettongia penicillata (Marsupialia: Potoroidae). Parasitology 135, 13291335.

J. Stevens and A. Rambaut (2001). Evolutionary rate differences in trypanosomes. Infection, Genetics and Evolution 1, 143150.

J. R. Stevens , H. A. Noyes , C. J. Schofield and W. Gibson (2001). The molecular evolution of Trypanosomatidae. Advances in Parasitology 48, 156.

K. Tamura , J. Dudley , M. Nei and S. Kumar (2007). MEGA4: Molecular evolutionary genetics analysis (MEGA) software version 4.0. Molecular Biology and Evolution 24, 15961599.

R. Tarlinton , J. Meers , J. Hanger and P. Young (2005). Real-time reverse transcriptase PCR for the endogenous koala retrovirus reveals an association between plasma viral load and neoplastic disease in koalas. Journal of General Virology 86, 783787.

M. Ziccardi and R. Lourenco-De-Oliveira (1999). Polymorphism in trypomastigotes of Trypanosoma (Megatrypanum) minasense in the blood of experimentally infected squirrel monkey and marmosets. Memorias do Instituto Oswaldo Cruz 94, 649653.

M. Ziccardi , R. Lourenco De Oliveira and R. Nogueira (1996). The haemoculture of Trypanosoma minasense Chagas, 1908. Memorias do Instituto Oswaldo Cruz 91, 501505.

Recommend this journal

Email your librarian or administrator to recommend adding this journal to your organisation's collection.

  • ISSN: 0031-1820
  • EISSN: 1469-8161
  • URL: /core/journals/parasitology
Please enter your name
Please enter a valid email address
Who would you like to send this to? *



Altmetric attention score

Full text views

Total number of HTML views: 6
Total number of PDF views: 16 *
Loading metrics...

Abstract views

Total abstract views: 443 *
Loading metrics...

* Views captured on Cambridge Core between September 2016 - 23rd June 2017. This data will be updated every 24 hours.