Department of Ecology & Evolutionary Biology, University of Toronto, 25 Willcocks Street, Toronto, ON, Canada M5S 3B2, Department of Natural History, Royal Ontario Museum, 100 Queen's Park, Toronto, ON, Canada M5S 2C6.
Mol Ecol Resour. 2009 May;9 Suppl s1:224-36. doi: 10.1111/j.1755-0998.2009.02648.x.
DNA barcoding has gained increased recognition as a molecular tool for species identification in various groups of organisms. In this preliminary study, we tested the efficacy of a 615-bp fragment of the cytochrome c oxidase I (COI) as a DNA barcode in the medically important family Simuliidae, or black flies. A total of 65 (25%) morphologically distinct species and sibling species in species complexes of the 255 recognized Nearctic black fly species were used to create a preliminary barcode profile for the family. Genetic divergence among congeners averaged 14.93% (range 2.83-15.33%), whereas intraspecific genetic divergence between morphologically distinct species averaged 0.72% (range 0-3.84%). DNA barcodes correctly identified nearly 100% of the morphologically distinct species (87% of the total sampled taxa), whereas in species complexes (13% of the sampled taxa) maximum values of divergence were comparatively higher (max. 4.58-6.5%), indicating cryptic diversity. The existence of sibling species in Prosimulium travisi and P. neomacropyga was also demonstrated, thus confirming previous cytological evidence about the existence of such cryptic diversity in these two taxa. We conclude that DNA barcoding is an effective method for species identification and discovery of cryptic diversity in black flies.
DNA 条形码技术作为一种分子工具，在各种生物类群的物种鉴定中得到了越来越多的认可。在这项初步研究中，我们测试了细胞色素氧化酶 I（COI）的 615bp 片段作为医学上重要的双翅目科（Simuliidae），即黑蝇的 DNA 条形码的功效。共有 65 种（25%）形态不同的物种和种复合体中的姊妹种，用于为该科创建初步的条形码图谱。近北极黑蝇的 255 种公认的近北极种的同属种之间的遗传分歧平均为 14.93%（范围为 2.83-15.33%），而形态不同的物种之间的种内遗传分歧平均为 0.72%（范围为 0-3.84%）。DNA 条形码几乎可以正确识别所有形态不同的物种（占采样总类群的 87%），而在种复合体中（占采样总类群的 13%），分歧的最大值相对较高（最大值为 4.58-6.5%），表明存在隐种多样性。Prosimulium travisi 和 P. neomacropyga 中姊妹种的存在也得到了证明，从而证实了以前关于这两个类群中存在这种隐种多样性的细胞学证据。我们得出结论，DNA 条形码是鉴定黑蝇物种和发现隐种多样性的有效方法。
