ABSTRACT Stenoperla helsoni is an endemic New Zealand stonefly characterised by distinctive sexually dimorphic wing loss. Previous distribution records indicated that this species was restricted to the South Island's Southern Alps, although our recent collections of wing-reduced specimens from a site in the Tararua Ranges suggest that this species may extend into the lower North Island. We amplified the mitochondrial COI gene to confirm the identity of North Island specimens, and to assess phylogeographic structuring within the species and genus. North Island specimens were confirmed as S. helsoni, indicating that this species has a much wider geographic range than previously thought. This broad distribution, combined with low levels of intraspecific divergence, suggests that female S. helsoni may be strong fliers, despite males being flightless. Distinct North Island and South Island populations were identified, with a 1.5% divergence between the two populations.

中文翻译：

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系统地理学揭示了新西兰唯一的有性翅双态石蝇（Stenoperla helsoni）的北岛范围扩展

摘要 Stenoperla helsoni 是一种新西兰特有的石蝇，其特征是具有独特的两性异形翅膀损失。先前的分布记录表明，该物种仅限于南岛的南阿尔卑斯山，尽管我们最近从塔拉鲁阿山脉的一个地点收集的翅膀缩小的标本表明该物种可能延伸到北岛下部。我们扩增了线粒体 COI 基因以确认北岛标本的身份，并评估物种和属内的系统地理学结构。北岛标本被确认为 S. helsoni，表明该物种的地理范围比以前认为的要广泛得多。这种广泛的分布，加上低水平的种内差异，表明雌性 S. helsoni 可能是强壮的飞行者，尽管雄性不会飞。确定了不同的北岛和南岛种群，两个种群之间的差异为 1.5%。