Black flies are insects of medical, veterinary, and environmental significance. Historically, they have attacked humans and caused simuliotoxicosis in livestock in the Aras River Basin in northwest Iran. However, information on the species and their bionomics is limited in the region. Adult flies were collected from diverse ecotopes of the Aras River Basin. After morphological identification, representative specimens of each morphological group were subjected to mtDNA COI gene sequence analysis for species diagnosis and to infer relationships. Flies also were examined for pollinia. A total of 1880 specimens representing 12 morphotaxa in two genera (Simulium and Metacnephia) were identified: Simulium turgaicum (n=1834), S. kiritshenkoi (n=12), S. bezzii (n=7), S. brevitarse (n=7), S. pseudequinum (n=5), S. aureum species group (n=4), S. vernum species group (n=3), S. transcaspicum (n=1), three unidentified species of the subgenus Simulium (n=5), and Metacnephia possibly persica (n=2). Fifty two haplotypes were detected for the 65 COI sequences analyzed. Intraspecific genetic divergence was 0.19-8.83%, whereas the mean interspecific genetic distances among the morphotaxa were 1.41-19.58%. Molecular analyses recovered three well-supported lineages within S. turgaicum. One lineage included black flies collected from agricultural fields, a second lineage involved black flies captured from animals, and a third lineage included specimens that had visited flowers, as evidenced by presence of pollinia. The relative abundance (97%) and observations of the S. turgaicum complex biting humans are important epidemiological factors. Future studies are needed to define the potential epidemiological risk of simulids in Khoda-Afarin County of Iran.

黑蝇是具有医学，兽医和环境意义的昆虫。从历史上看，他们袭击了人类，并在伊朗西北部阿拉斯河流域的牲畜中造成了类似毒素中毒。但是，有关物种及其生物组学的信息在该地区有限。从阿拉斯河流域的不同生态环境中收集成年苍蝇。进行形态学鉴定后，对每个形态学组的代表性标本进行mtDNA COI基因序列分析，以进行物种诊断和推断关系。还检查了果蝇的花粉症。共有1880个标本代表两个属（12 morphotaxa蚋和Metacnephia）被确定：蚋turgaicum（N = 1834），S. kiritshenkoi（N = 12），S。bezzii（N = 7），S. brevitarse（N = 7），S. pseudequinum（N = 5），S.萝物种组（n = 4），S. vernum种组（n = 3），S. transcaspicum（N = 1），亚属的三名身份不明物种蚋（N = 5），和Metacnephia可能桃（N = 2）。对于所分析的65个COI序列，检测到52个单倍型。种内遗传差异为0.19-8.83％，而形态间的平均种间遗传距离为1.41-19.58％。分子分析在S. turgaicum中回收了三个支撑良好的谱系。一种谱系包括从农田收集的黑蝇，另一种谱系包括从动物身上捕获的黑蝇，第三种谱系包括已经探访过花的标本，如存在花粉症。turgaicum复合物咬人的相对丰度（97％）和观察结果是重要的流行病学因素。需要进一步的研究来确定伊朗科达-阿法林县类似物的潜在流行病学风险。