Genetic evolutionary characteristics of and prevalence of parasitic infections in tabanid flies in Shiqu County, eastern Qinghai-Tibet Plateau

doi:10.12140/j.issn.1000-7423.2026.02.015

Abstract

Abstract:

Objective To investigate the distribution characteristics of and prevalence of parasitic infections in tabanid flies in Shiqu County, eastern Qinghai-Tibet Plateau, so as to provide baseline data for understanding tabanid fly distribution patterns and formulation of tabanid-borne disease control strategies in this region. Methods Tabanid samples were collected from Nixia Town, Sexu Town, and Luoxu Town of Shiqu County, Sichuan Province using a net trapping method from 10:00 to 14:00 in August 2023 and August 2025. Genomic DNA was extracted from tabanid samples, and target fragments were amplified and sequenced using 28S rRNA-specific primers. Sequences were assembled using the Geneious Prime software, and the species was identified with the BLAST tool in the GenBank database. Haplotype diversity was calculated using the DnaSP software, and saturation of base substitutions was tested with the DAMBE software. Nucleotide substitution models were screened with the jModelTest tool, and a phylogenetic tree was generated with the maximum likelihood method using the MEGA software. High-throughput sequencing was performed with universal parasite primers, and sequencing data were subjected to quality control, paired-end assembly, operational taxonomic unit (OTU) clustering to detect potential parasites in tabanid samples. Results A total of 324 tabanid specimens were sampled, and 304 valid samples were obtained following identification and screening, which belonged to three genera and three species, including Hybomitra bimaculate (Tabanidae), Tabanus rufofrator (Tabanidae), and Symphoromyia hirta (Rhagionidae). T. rufofrator was the dominant species (275 individuals, 90.4%, 275/304), and 24 (7.89%, 24/304) H. bimaculate and 5 S. hirta (1.65%, 5/304) were identified. Totally eight haplotypes were detected, including two for H. bimaculata and three each for T. rufofrator and S. hirta. Phylogenetic analysis revealed clear differentiation structures of the study sequences at family, genus, and species levels. Two H. bimaculata haplotypes (H3 and H4) were clustered into the same clade with the reference sequence with the GenBank accession number of M243434, and three T. rufofrator haplotypes (H1, H6 and H8) were clustered into the monophyletic clade with the reference sequence with the GenBank accession number of AF238561, while three S. hirta haplotypes (H2, H5 and H7) and the reference sequence with the GenBank accession number of AF238558 generated a highly supported monophyletic clade. High-throughput sequencing yielded 1 499 OUT, which contained two potential parasite-associated OUT, including Mastophorus muris and Romanomermis iyengari, which were only present in H. bimaculate, while no parasites were detected in T. rufofrator or S. hirta. Conclusion T. rufofrator is the dominant species of the tabanid fly community in Shiqu County, with an overall low genetic diversity. Low-abundance nematode sequences are detected in H. bimaculate, suggesting the potential ecological significance in the transmission of tabanid-borne pathogens on the Qinghai-Tibet Plateau.

Key words: Blood-sucking insect, Tabanid, Genetic evolution, Qinghai-Tibet Plateau, Shiqu

CLC Number:

R384.22

LI Mengqing, WANG Xu, YANG Yang, XUE Chuizhao, ZUO Qingqiu, YIN Jianhai, CAO Jianping. Genetic evolutionary characteristics of and prevalence of parasitic infections in tabanid flies in Shiqu County, eastern Qinghai-Tibet Plateau[J]. CHINESE JOURNAL OF PARASITOLOGY AND PARASITIC DISEASES, 2026, 44(2): 252-259.

Figures/Tables 3

Table 1

Fig. 1

Fig. 2

References 41

[1]	Votypka J, Brzoňová J, Je?ek J, et al. Horse flies (Diptera: Tabanidae) of three West African countries: a faunistic update, barcoding analysis and trypanosome occur-rence[J]. Acta Trop, 2019, 197: 105069.
[2]	Morita SI, Bayless KM, Yeates DK, et al. Molecular phylogeny of the horse flies: a framework for renewing tabanid taxonomy[J]. Syst Entomol, 2016, 41(1): 56-72.
[3]	Baldacchino F, Desquesnes M, Mihok S, et al. Tabanids: neglected subjects of re-search, but important vectors of disease agents![J]. Infect Genet Evol, 2014, 28: 596-615.
[4]	Amaral AP, Borkent A, Baranov VA, et al. First fossil mosquito larva in 99-million-year-old amber with a modern type of morphology sheds light on the evolutionary history of mosquitoes (Diptera ∶ Culicidae)[J]. Gondwana Res, 2026, 150: 154-162.
[5]	European Centre for Disease Prevention and Control. Fleas (Siphonaptera)-Factsheet for health professionals[EB/OL]. (2021-11-09)[2026-01-10]. https://www.ecdc.europa.eu/en/infectious-di-sease-topics/related-public-health-topics/disease-vectors/facts/fleas-siphonaptera.
[6]	Qi NS, Zhang X, Liao SQ, et al. Detection of dengue virus serotype 1 from gadfly in China[J]. J Infect, 2023, 87(3): 277-279.
[7]	章翔, 程蓉蓉, 刘路瑶, 等. 安徽省金寨县大别山地区野生虻Tabanus hypomacros可作为非洲猪瘟病毒机械传播媒介初探[J]. 中国媒介生物学及控制杂志, 2022, 33(3): 326-330.
	Zhang X, Cheng RR, Liu LY, et al. Tabanus hypomacros: a suspected mechanical transmission vector of African swine fever virus in Dabie Mountain region of Jinzhai County, Anhui Province in China[J]. Chin J Vector Biol Control, 2022, 33(3): 326-330. (in Chinese)
[8]	Dyonisio GHS, Batista HR, da Silva RE, et al. Molecular diagnosis and prevalence of Trypanosoma vivax (Trypanosomatida∶Trypanosomatidae) in buffaloes and ecto-parasites in the Brazilian Amazon Region[J]. J Med Entomol, 2021, 58(1): 403-407.
[9]	Kelly-Hope L, Paulo R, Thomas B, et al. Loa loa vectors Chrysops spp. Perspectives on research, distribution, bionomics, and implications for elimination of lymphatic fila-riasis and onchocerciasis[J]. Parasit Vectors, 2017, 10(1): 172.
[10]	Petersen JM, Mead PS, Schriefer ME. Francisella tularensis: An arthropod-borne pathogen[J]. Vet Res, 2009, 40(2): 7.
[11]	Narladkar BW. Projected economic losses due to vector and vector-borne parasitic diseases in livestock of India and its significance in implementing the concept of integrated practices for vector management[J]. Vet World, 2018, 11(2): 151-160.
[12]	Yang L, Wiegmann BM, Yeates DK, et al. Higher-level phylogeny of the Therevidae (Diptera ∶ Insecta) based on 28S ribosomal and elongation factor-1 alpha gene sequences[J]. Mol Phylogenet Evol, 2000, 15(3): 440-451.
[13]	何静, 刘荣堂, 刘增加. 我国虻科研究进展[J]. 中华卫生杀虫药械, 2006, 12(4): 248-252.
	He J, Liu RT, Liu ZJ. Study development of Tabanidae[J]. Chin J Hyg Insectic Equip, 2006, 12(4): 248-252. (in Chinese)
[14]	干珠扎布, 胡国铮, 高清竹, 等. 藏北高原草地生态治理与畜牧业协同发展模式研究[J]. 中国工程科学, 2019, 21(5): 93-98.
	Ganzhu ZB, Hu GZ, Gao QZ, et al. Synergetic mode for grassland ecological management and animal husbandry development in northern Tibet Plateau[J]. Eng Sci, 2019, 21(5): 93-98. (in Chinese)
[15]	Cuthbert RN, Darriet F, Chabrerie O, et al. Invasive hematophagous arthropods and associated diseases in a changing world[J]. Parasit Vectors, 2023, 16(1): 291.
[16]	De Liberato C, Magliano A, Autorino GL, et al. Seasonal succession of tabanid species in equine infectious anaemia endemic areas of Italy[J]. Med Vet Entomol, 2019, 33(3): 431-436.
[17]	Sanal Demirci SN, Kilic V, Mutun S, et al. Population genetics and phylogeography of Tabanus bromius (Diptera ∶ Tabanidae)[J]. Parasit Vectors, 2021, 14(1): 453.
[18]	Mackerras IM, Spratt DM, Yeates DK. Revision of the horse fly Genera Lissimas and Cydistomyia (Diptera ∶ Tabanidae ∶ Diachlorini) of Australia[J]. Zootaxa, 2008, 1886(1): 1-80.
[19]	Kumar S, Stecher G, Tamura K. MEGA7: molecular evolutionary genetics analysis version 7.0 for bigger datasets[J]. Mol Biol Evol, 2016, 33(7): 1870-1874.
[20]	Rozas J, Ferrer-Mata A, Sánchez-DelBarrio JC, et al. DnaSP 6: DNA sequence polymorphism analysis of large data sets[J]. Mol Biol Evol, 2017, 34(12): 3299-3302.
[21]	Xia XH. DAMBE7: new and improved tools for data analysis in molecular biology and evolution[J]. Mol Biol Evol, 2018, 35(6): 1550-1552.
[22]	Darriba D, Taboada GL, Doallo R, et al. jModelTest 2: more models, new heuristics and parallel computing[J]. Nat Methods, 2012, 9(8): 772.
[23]	Cannon MV, Bogale H, Rutt L, et al. A high-throughput sequencing assay to comprehensively detect and characterize unicellular eukaryotes and helminths from biological and environmental samples[J]. Microbiome, 2018, 6(1): 195.
[24]	Dillon ME, Frazier MR, Dudley R. Into thin air: physiology and evolution of alpine insects[J]. Integr Comp Biol, 2006, 46(1): 49-61.
[25]	Lucas M, Krolow TK, Riet-Correa F, et al. Diversity and seasonality of horse flies (Diptera ∶ Tabanidae) in Uruguay[J]. Sci Rep, 2020, 10(1): 401.
[26]	Kniepert FW. Blood-feeding and nectar-feeding in adult Tabanidae (Diptera)[J]. Oecologia, 1980, 46(1): 125-129.
[27]	张春田. 辽宁的吸血虻类及其生态习性的观察[J]. 沈阳师范大学学报(自然科学版), 1995, 13(4): 42-46.
	Zhang CT. Observation on blood-sucking flies and their ecological habits in Liaoning Province[J]. J Shenyang Norm Univ Nat Sci Ed, 1995, 13(4): 42-46. (in Chinese)
[28]	Wiegmann BM, Tsaur SC, Webb DW, et al. Monophyly and relationships of the Tabanomorpha (Diptera∶Brachycera) based on 28S ribosomal gene sequences[J]. An, 2000, 93(5): 1031-1038.
[29]	Turner WJ. A revision of the genus Symphoromyia Frauenfeld (Diptera ∶ Rhagionidae): I. Introduction. Subgenera and species-groups. Review of biology[J]. Can Entomol, 1974, 106(8): 851-868.
[30]	Magnarelli LA, Anderson JF. Feeding behavior of Tabanidae (Diptera) on cattle and serologic analyses of partial blood meals[J]. Environ Entomol, 1980, 9(5): 664-667.
[31]	Marshall KE, Sinclair BJ. Repeated stress exposure results in a survival-reproduction trade-off in Drosophila melanogaster[J]. Proc Biol Sci, 2010, 277(1683): 963-969.
[32]	Shama LN, Kubow KB, Jokela J, et al. Bottlenecks drive temporal and spatial genetic changes in alpine caddisfly metapopulations[J]. BMC Evol Biol, 2011, 11: 278.
[33]	Song W, Cao LJ, Li BY, et al. Multiple refugia from penultimate glaciations in East Asia demonstrated by phylogeography and ecological modelling of an insect pest[J]. BMC Evol Biol, 2018, 18(1): 152.
[34]	Keesing F, Belden LK, Daszak P, et al. Impacts of biodiversity on the emergence and transmission of infectious diseases[J]. Nature, 2010, 468(7324): 647-652.
[35]	何静, 刘增加, 刘荣堂. 甘肃省虻科昆虫区系研究[J]. 寄生虫与医学昆虫学报, 2006, 13(4): 226-235.
	He J, Liu ZJ, Liu RT. Study on the fauna of Tabanidae in Gansu[J]. Acta Parasitol Med Entomol Sin, 2006, 13(4): 226-235. (in Chinese)
[36]	李树森, 杨祖德. 太白山南坡吸血虻类的垂直分布及区系分析[J]. 昆虫学报, 1993, 36(3): 340-346.
	Li SS, Yang ZD. Fauna of Tabanidae on the southern slope of Taibai Mts. as influenced by elevation[J]. Acta Entomol Sin, 1993, 36(3): 340-346. (in Chinese)
[37]	Ge HR, Zhang HN, Meng R, et al. Phylogenetic and genetic evolutionary analyses of the mitochondrial genome of Mastophorus muris in Neodon fuscus from the Qinghai-Tibetan Plateau[J]. Microbiol Spectr, 2025, 13(8): e0306724.
[38]	McGarry JW, Higgins A, White NG, et al. Zoonotic helminths of urban brown rats (Rattus norvegicus) in the UK: neglected public health considerations?[J]. Zoonoses Public Health, 2015, 62(1): 44-52.
[39]	Behnke JM, Jackson JA, Gilbert F, et al. Large-bodied gastric spirurids (Nematoda, Spirurida) predict structure in the downstream gastrointestinal helminth community of wild spiny mice (Acomys dimidiatus)[J]. Parasitology, 2024, 151(8): 808-820.
[40]	Abagli AZ, Alavo TBC, Perez-Pacheco R, et al. Efficacy of the mermithid nematode, Romanomermis iyengari, for the biocontrol of Anopheles gambiae, the major malaria vector in sub-Saharan Africa[J]. Parasit Vectors, 2019, 12(1): 253.
[41]	罗春花, 袁珩, 李文博, 等. 2018—2023年四川省人间炭疽流行病学特征分析[J]. 预防医学情报杂志, 2024, 40(8): 905-910.
	Luo CH, Yuan H, Li WB, et al. Analysis of epidemiological characteristics of human Anthrax in Sichuan Province from 2018 to 2023[J]. J Prev Med Inf, 2024, 40(8): 905-910. (in Chinese)

物种 Species	引物 Primer	引物序列（5'→3'） Primer sequence (5'→3')	产物长度/bp Product length/bp	退火温度/℃ Annealing temperature/℃
无脊椎动物 Invertebrate	JB	F-TTTTTTGGGCATCCTGAGGTTTAT	440	55.0
	JB	R-TAAAGAAAGAACATAATGAAAATG	440	55.0
阿米巴门 Amoebozoa	Amo	F-GAATTGACGGAAGGGCACAC	333~420	57.8
	Amo	R-GCCCYRTCTAAGGGCATCAC	333~420	57.8
顶复门A Apicomplexa A	Api-A	F-GACCTATCAGCTTTCGACGG	244~248	55.0
	Api-A	R-CCCTCCAATTGWTACTCTGGR	244~248	55.0
顶复门B Apicomplexa B	Api-B	F-TGYGTTTGAATACTAYAGCATGG	228~244	53.7
	Api-B	R-TCTGATCGTCTTCACTCCCTT	228~244	53.7
顶复门 Apicomplexa	Api-C	F-TTGGMCTACCGTGGCARTGA	420~427	57.5
	Api-C	R-TCAAGGCAAHWGCCTGCTT	420~427	57.5
芽囊原虫属 Blastocystis	Bla	F-TGGTCGCAAGGCTGAAACTT	303~307	58.1
	Bla	R-TTGCCTCCAGCTTCCCTACA	303~307	58.1
双滴虫目 Diplomonadida	Dip	F-RGGGACRGGTGAAATAGGATG	277~285	56.5
	Dip	R-CAAATTGAGCCGCAGACTCC	277~285	56.5
动质体门 Kinetoplastida	Kin	F-AAATTAAACCGCACGCTCCA	250~300	55.4
	Kin	R-GCAAACGATGACACCCATGA	250~300	55.4
小孢子虫门 Microsporidia	Mic	F-BCAGGTTGATTCTGCCTGACR	370~440	57.9
	Mic	R-ACCAGWCTTGCCCTCCARTT	370~440	57.9
副基体纲 Parabasalia	Par	F-TAGGCTATCACGGGTAACGG	326~364	55.3
	Par	R-GCGTCCTGATTTGTTCACAG	326~364	55.3
扁形动物门 Platyhelminthes	Pla	F-CAATTGGAGGGCAAGTCTGG	350~550	55.4
	Pla	R-TGCTTTCGCWKTAGTTTGTCTG	350~550	55.4
线虫动物门A Nematode A	Nem-A	F-CACCCGTGAGGATTGACAG	320~335	54.1
	Nem-A	R-CGATCACGGAGGATTTTCAA	320~335	54.1
线性动物门B Nematode B	Nem-B	F-CGTCATTGCTGCGGTTAAAA	380~410	56.0
	Nem-B	R-CCGTCCTTCGAACCTCTGAC	380~410	56.0
线性动物门C Nematode C	Nem-C	F-AGTGGAGCATGCGGCTTAAT	380~440	56.6
	Nem-C	R-TGCAATTCCCTRTCCCAGTC	380~440	56.6