UNLABELLED: Currently, new species of freshwater fish trypanosomes, which are economically important parasites, are being described based on subjectively selected features, i.e., their cell morphology and the host species. We have performed detailed phylogenetic and haplotype diversity analyses of all 18S rRNA genes available for freshwater fish trypanosomes, including the newly obtained sequences of Trypanosoma carassii and Trypanosoma danilewskyi. Based on a sequence similarity of 99.5%, we divide these trypanosomes into 15 operational taxonomic units, and propose three nominal scenarios for distinguishing T. carassii and other aquatic trypanosomes. We find evidences for the existence of a low number of freshwater fish trypanosomes, with T. carassii having the widest geographic and host ranges. Our analyses support the existence of an umbrella complex composed of T. carassii and two sister species. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s42995-023-00191-0.

BGI Genomics BGI Shenzhen Shenzhen 518083 China

Biomedical Research Centre School of Science Engineering and Environment University of Salford Salford M5 4WT UK

Guangdong Provincial Key Laboratory of Aquatic Economic Animals State Key Laboratory of Biocontrol School of Life Sciences Sun Yat sen University Guangzhou 510275 China

Institute of Parasitology Biology Centre Czech Academy of Sciences České Budějovice 37005 Czech Republic

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Baker JR. Trypanosomes and dactylosomes from the blood of fresh-water fish in East Africa. Parasitology. 1960;50:515–526. doi: 10.1017/S0031182000025592. PubMed DOI

Becker CD. Trypanosoma occidentalis sp. n. from freshwater teleosts in Washington State. J Parasitol. 1967;14:153–156.

Bienek DR, Plouffe DA, Wiegertjes GF, Belosevic M. Immunization of goldfish with excretory/secretory molecules of Trypanosoma danilewskyi confers protection against infection. Dev Comp Immunol. 2002;26:649–657. doi: 10.1016/S0145-305X(02)00018-6. PubMed DOI

Burreson EM, Pratt I. Trypanosoma pacifica sp. n. from the English sole Parophrys vetulus Girard from Oregon. J Parasitol. 1972;19:555–556. PubMed

Chen K, Zhang P, Yang TB, Wen YZ, Hide G, Lun ZR, Lai DH. Nile tilapia (Oreochromis niloticus) can be experimentally infected with both marine and fresh water fish trypanosomes. Exp Parasitol. 2022;239:108288. doi: 10.1016/j.exppara.2022.108288. PubMed DOI

Díaz AG, Ragone PG, Rusman F, Floridia-Yapur N, Barquez RM, Díaz MM, Tomasini N, Diosque P. A novel genotype and first record of Trypanosoma lainsoni in Argentina. Pathogens. 2020;99:731. doi: 10.3390/pathogens9090731. PubMed DOI PMC

Dyková I, Lom J. Histopathological changes in Trypanosoma danilewskyi Laveran & Mesnil, 1904 and Trypanoplasma borelli Laveran & Mesnil, 1902 infections of goldfish, Carassius auratus (L.) J Fish Dis. 1979;2:381–390. doi: 10.1111/j.1365-2761.1979.tb00390.x. DOI

Eiras JC, Takemoto RM, Pavanelli GC, Luque JL. Checklist of protozoan parasites of fishes from Brazil. Zootaxa. 2012;3221:1–25. doi: 10.11646/zootaxa.3221.1.1. DOI

Feng S, Woo PT. Identification of carbohydrates on the surface membrane of pathogenic and nonpathogenic piscine haemoflagellates, Cryptobia salmositica, C. bullocki and C. catostomi (Kinetoplastida) Dis Aquat Org. 1998;32:201–209. doi: 10.3354/dao032201. PubMed DOI

Gibson WC, Lom J, Pecková H, Ferris VR, Hamilton PB. Phylogenetic analysis of freshwater fish trypanosomes from Europe using SSU rRNA gene sequences and random amplification of polymorphic DNA. Parasitology. 2005;130:405–412. doi: 10.1017/S0031182004006778. PubMed DOI

Gibson W, Kay C, Peacock L. Trypanosoma congolense: molecular toolkit and resources for studying a major livestock pathogen and model trypanosome. Adv Parasitol. 2017;98:283–309. doi: 10.1016/bs.apar.2017.03.002. PubMed DOI

Grybchuk-Ieremenko A, Losev A, Kostygov AY, Lukeš J, Yurchenko V. High prevalence of trypanosome co-infections in freshwater fishes. Folia Parasitol. 2014;61:495. doi: 10.14411/fp.2014.064. PubMed DOI

Gu Z, Wang J, Zhang J, Gong X. Redescription of Trypanosoma ophiocephali Chen 1964 (Kinetoplastida: Trypanosomatina: Trypanosomatidae) and first record from the blood of dark sleeper (Odontobutis obscura Temminck and Schlegel) in China. Parasitol Res. 2006;100:149–154. doi: 10.1007/s00436-006-0247-3. PubMed DOI

Gu Z, Wang J, Li M, Zhang J, Gong X. Redescription of Trypanosoma siniperca Chang 1964 from freshwater fish of China based on morphological and molecular data. Parasitol Res. 2007;100:395–400. doi: 10.1007/s00436-006-0355-0. PubMed DOI

Gu Z, Wang J, Li M, Zhang J, Ke X, Gong X. Morphological and genetic differences of Trypanosoma in some Chinese freshwater fishes: difficulties of species identification. Parasitol Res. 2007;101:723–730. doi: 10.1007/s00436-007-0536-5. PubMed DOI

Gupta N, Gupta DK. Erythropenia in piscine trypanosomiasis. Trends Parasitol Res. 2012;1:1–6.

Gupta DK, Gupta N, Gangwar R. Two new species of Trypanosoma from freshwater fish (Heteropneustes fossilis and Channa punctatus) from Bareilly. India Parasit Dis. 2006;30:58–63.

Hagen MO, Katzenback BA, Islam MD, Gamal El-Din M, Belosevic M. The analysis of goldfish (Carassius auratus L.) innate immune responses after acute and subchronic exposures to oil sands process-affected water. Toxicol Sci. 2014;138:59–68. doi: 10.1093/toxsci/kft272. PubMed DOI PMC

Hamilton PB, Stevens JR. Classification and phylogeny of Trypanosomacruzi. In: Telleria J, Tibayrenc M, editors. American trypanosomiasis chagas disease. Amsterdam: Elsevier; 2017. pp. 321–344.

Hoare CA. The trypanosomes of mammals. A zoological monograph. Oxford and Edinburgh: Blackwell Scientific; 1972.

Islam N, Woo PT. Anemia and its mechanism in goldfish Carassius auratus infected with Trypanosoma danilewskyi. Dis Aquat Org. 1991;11:37–43. doi: 10.3354/dao011037. DOI

Jansen AM, Xavier SCC, Roque ALR. Ecological aspects of Trypanosomacruzi: wild hosts and reservoirs. In: Telleria J, Tibayrenc M, editors. American trypanosomiasis chagas disease: one hundred years of research. Amsterdam: Elsevier; 2017. pp. 243–264.

Jesus RB, Gallani SU, Valladão GMR, Pala G, da Silva TFA, da Costa JC, Pilarski F. Trypanosomiasis causing mortality outbreak in Nile tilapia intensive farming: identification and pathological evaluation. Aquaculture. 2018;491:169–176. doi: 10.1016/j.aquaculture.2018.02.002. DOI

Jiang B, Lu G, Du J, Wang J, Hu Y, Su Y, Li A. First report of trypanosomiasis in farmed largemouth bass (Micropterus salmoides) from China: pathological evaluation and taxonomic status. Parasitol Res. 2019;118:1731–1739. doi: 10.1007/s00436-019-06323-9. PubMed DOI

Jirků M, Kolesnikov AA, Benada O, Lukeš J. Marine fish and ray trypanosomes have large kinetoplast minicircle DNA. Mol Biochem Parasitol. 1995;73:279–283. doi: 10.1016/0166-6851(95)00121-G. PubMed DOI

Khan RA. The life cycle of Trypanosoma murmanensis Nikitin. Can J Zool. 1976;54:1840–1849. doi: 10.1139/z76-214. PubMed DOI

Khan RA. Pathogenesis of Trypanosoma murmanensis in marine fish of the northwestern Atlantic following experimental transmission. Can J Zool. 1985;63:2141–2144. doi: 10.1139/z85-315. DOI

Kostygov AY, Karnkowska A, Votýpka J, Tashyreva D, Maciszewski K, Yurchenko V, Lukeš J. Euglenozoa: taxonomy, diversity and ecology, symbioses and viruses. Open Biol. 2021;11:200407. doi: 10.1098/rsob.200407. PubMed DOI PMC

Kovacevic N, Belosevic M. Molecular and functional characterization of goldfish (Carassius auratus L.) Serum Amyloid A. Fish Shellfish Immunol. 2015;47:942–953. doi: 10.1016/j.fsi.2015.10.041. PubMed DOI

Kovacevic N, Hagen MO, Xie J, Belosevic M. The analysis of the acute phase response during the course of Trypanosoma carassii infection in the goldfish (Carassius auratus L.) Dev Comp Immunol. 2015;53:112–122. doi: 10.1016/j.dci.2015.06.009. PubMed DOI

Kumar S, Stecher G, Tamura K. MEGA7: molecular evolutionary genetics analysis version 7.0 for bigger datasets. Mol Biol Evol. 2016;33:1870–1874. doi: 10.1093/molbev/msw054. PubMed DOI PMC

Lemos M, Fermino BR, Simas-Rodrigues C, Hoffmann L, Silva R, Camargo EP, Teixeira MM, Souto-Padrón T. Phylogenetic and morphological characterization of trypanosomes from Brazilian armoured catfishes and leeches reveal high species diversity, mixed infections and a new fish trypanosome species. Parasit Vectors. 2015;8:573. doi: 10.1186/s13071-015-1193-7. PubMed DOI PMC

Letch CA. Host restriction, morphology and isoenzymes among trypanosomes of some British freshwater fishes. Parasitology. 1979;79:107–117. doi: 10.1017/S0031182000052008. DOI

Letch C. The life-cycle of Trypanosoma cobitis Mitrophanow 1883. Parasitology. 1980;80:163–169. doi: 10.1017/S0031182000000627. DOI

Lima L, Espinosa-Álvarez O, Ortiz PA, Trejo-Varón JA, Carranza JC, Pinto CM, Serrano MG, Buck GA, Camargo EP, Teixeira MM. Genetic diversity of Trypanosoma cruzi in bats, and multilocus phylogenetic and phylogeographical analyses supporting Tcbat as an independent DTU (discrete typing unit) Acta Trop. 2015;151:166–177. doi: 10.1016/j.actatropica.2015.07.015. PubMed DOI

Lom J. Biology of the trypanosomes and trypanoplasms of fish. In: Lumsden WHR, Evans DA, editors. Biology of the kinetoplastida. London: Academic Press; 1979. pp. 269–337.

Lom J, Dyková I. Protozoan parasites of fishes. Developments in aquaculture and fisheries sciences. Amsterdam: Elsevier; 1992.

Lu B, Hu X, Warren A, Song W, Yan Y. From oral structure to molecular evidence: new insights into the evolutionary phylogeny of the ciliate order Sessilida (Protista, Ciliophora), with the establishment of two new families and new contributions to the poorly studied family Vaginicolidae. Sci China Life Sci. 2023;66:1535–1553. doi: 10.1007/s11427-022-2268-2. PubMed DOI

Luo D, Xu LW, Liu XH, Sato H, Zhang JY. Outbreak of trypanosomiasis in net-cage cultured barramundi, Lates calcarifer (Perciformes, Latidae), associated with Trypanosoma epinepheli (Kinetoplastida) in South China Sea. Aquaculture. 2019;501:219–223. doi: 10.1016/j.aquaculture.2018.11.029. DOI

Mackerras MJ, Mackerras IM. The haematozoa of Australian frogs and fish. Aust J Zool. 1961;9:123–139. doi: 10.1071/ZO9610123. DOI

Marcili A, Lima L, Valente VC, Valente SA, Batista JS, Junqueira AC, Souza AI, da Rosa JA, Campaner M, Lewis MD, Llewellyn MS, Miles MA, Teixeira MM. Comparative phylogeography of Trypanosoma cruzi TCIIc: new hosts, association with terrestrial ecotopes, and spatial clustering. Infect Genet Evol. 2009;9:1265–1274. doi: 10.1016/j.meegid.2009.07.003. PubMed DOI

Maslov DA, Votýpka J, Yurchenko V, Lukeš J. Diversity and phylogeny of insect trypanosomatids: all that is hidden shall be revealed. Trends Parasitol. 2013;29:43–52. doi: 10.1016/j.pt.2012.11.001. PubMed DOI

Negm-Eldin MM. Further studies on Trypanosoma mukasai Hoare, 1932 and its biological vector Batracobdelloides tricarinata (Blanchard, 1897) Deutsch Tierarztl Wochenschr. 1998;105:175–181. PubMed

Noyes HA, Ambrose P, Barker F, Begon M, Bennet M, Bown KJ, Kemp SJ. Host specificity of Trypanosoma (Herpetosoma) species: evidence that bank voles (Clethrionomys glareolus) carry only one T. (H.) evotomys 18S rRNA genotype but wood mice (Apodemus sylvaticus) carry at least two polyphyletic parasites. Parasitology. 2002;124:185–190. doi: 10.1017/S0031182001001019. PubMed DOI

Qadri SS. On three new trypanosomes from freshwater fishes. Parasitology. 1962;52:221–228. doi: 10.1017/S0031182000024185. DOI

Šlapeta J, Morin-Adeline V, Thompson P, McDonell D, Shiels M, Gilchrist K, Votýpka J, Vogelnest L. Intercontinental distribution of a new trypanosome species from Australian endemic Regent Honeyeater (Anthochaera phrygia) Parasitology. 2016;143:1012–1025. doi: 10.1017/S0031182016000329. PubMed DOI

Smit NJ, Joubert A, Lawton SP, Hayes PM, Cook CA. Morphological and molecular characterization of an African freshwater fish trypanosome, including its development in a leech vector. Int J Parasitol. 2020;50:921–929. doi: 10.1016/j.ijpara.2020.06.004. PubMed DOI

Stevens JR, Teixeira MM, Bingle LE, Gibson WC. The taxonomic position and evolutionary relationships of Trypanosoma rangeli. Int J Parasitol. 1999;29:749–757. doi: 10.1016/S0020-7519(99)00016-8. PubMed DOI

Su Y, Feng J, Jiang J, Guo Z, Liu G, Xu L. Trypanosoma epinepheli n. sp. (Kinetoplastida) from a farmed marine fish in China, the brown-marbled grouper (Epinephelus fuscoguttatus) Parasitol Res. 2014;113:11–18. doi: 10.1007/s00436-013-3626-6. PubMed DOI

Su BX, Wang JF, Yang TB, Hide G, Lai DH, Lun ZR. A new species of mammalian trypanosome, Trypanosoma (Megatrypanum) bubalisi sp. nov., found in the freshwater leech Hirudinaria manillensis. Int J Parasitol. 2022;52:253–264. doi: 10.1016/j.ijpara.2021.10.009. PubMed DOI

Thompson JD, Gibson TJ, Plewniak F, Jeanmougin F, Higgins DG. The CLUSTAL_X windows interface: flexible strategies for multiple sequence alignment aided by quality analysis tools. Nucleic Acids Res. 1997;25:4876–4882. doi: 10.1093/nar/25.24.4876. PubMed DOI PMC

Wang R, Belosevic M. Estradiol increases susceptibility of goldfish to Trypanosoma danilewskyi. Dev Comp Immunol. 1994;18:377–387. doi: 10.1016/0145-305X(94)90003-5. PubMed DOI

Wen YZ, Lun ZR, Zhu XQ, Hide G, Lai DH. Further evidence from SSCP and ITS DNA sequencing support Trypanosoma evansi and Trypanosoma equiperdum as subspecies or even isolates of Trypanosoma brucei. Infect Genet Evol. 2016;41:56–62. doi: 10.1016/j.meegid.2016.03.022. PubMed DOI

Woo PK. Trypanosoma danilewskyi: a new multiplication process for Trypanosoma (Protozoa: Kinetoplastida) J Parasitol. 1981;67:522–526. doi: 10.2307/3280484. DOI

Woo PTK, Poynton SL. Diplomonadida, kinetoplastida and amoebida (phylum sarcomastigophora) In: Woo PTK, editor. Fish diseases and disorders. Wallingford: CABI; 1998. pp. 27–96.

Zajíček P, Lukeš J. The differentiation between freshwater and marine fish trypanosomes by lectin agglutinability. Folia Parasitol. 1992;39:195–200. PubMed

Zajíček P, Pecková H. A comparison of morphology, growth rate and selected enzyme activities among freshwater fish trypanosomes and the marine species Trypanosoma boissoni. Arch Protistenkdn. 1995;146:95–100. doi: 10.1016/S0003-9365(11)80261-7. DOI

Zhang P, Chen K, Svobodová M, Yang TB, Lukeš J, Zhang JY, Lun ZR, Lai DH. Does the fish-infecting Trypanosoma micropteri belong to Trypanosoma carassii? Folia Parasitol. 2022;69:024. doi: 10.14411/fp.2022.024. PubMed DOI

Zingales B, Andrade SG, Briones MR, Campbell DA, Chiari E, Fernandes O, Guhl F, Lages-Silva E, Macedo AM, Machado CR, Miles MA, Romanha AJ, Sturm NR, Tibayrenc M, Schijman AG, Meeting SS. A new consensus for Trypanosoma cruzi intraspecific nomenclature: second revision meeting recommends TcI to TcVI. Mem Inst Oswaldo Cruz. 2009;104:1051–1054. doi: 10.1590/S0074-02762009000700021. PubMed DOI