Data from: Untangling taxonomy: a DNA barcode reference library for Canadian spiders

Approximately 1460 species of spiders have been reported from Canada, 3% of the global fauna. This study provides a DNA barcode reference library for 1018 of these species based upon the analysis of more than 30 000 specimens. The sequence results show a clear barcode gap in most cases with a mean intraspecific divergence of 0.78% vs. a minimum nearest-neighbour (NN) distance averaging 7.85%. The sequences were assigned to 1359 Barcode index numbers (BINs) with 1344 of these BINs composed of specimens belonging to a single currently recognized species. There was a perfect correspondence between BIN membership and a known species in 795 cases, while another 197 species were assigned to two or more BINs (556 in total). A few other species (26) were involved in BIN merges or in a combination of merges and splits. There was only a weak relationship between the number of specimens analysed for a species and its BIN count. However, three species were clear outliers with their specimens being placed in 11–22 BINs. Although all BIN splits need further study to clarify the taxonomic status of the entities involved, DNA barcodes discriminated 98% of the 1018 species. The present survey conservatively revealed 16 species new to science, 52 species new to Canada and major range extensions for 426 species. However, if most BIN splits detected in this study reflect cryptic taxa, the true species count for Canadian spiders could be 30–50% higher than currently recognized.

目前已在加拿大报道的蜘蛛物种约有1460种，占全球蜘蛛区系的3%。本研究通过对3万余号标本的分析，为其中1018种蜘蛛构建了DNA条形码（DNA barcode）参考文库。序列分析结果显示，绝大多数类群存在清晰的条形码间隙（barcode gap）：种内平均分歧率为0.78%，而最近邻（nearest-neighbour, NN）的最小平均距离为7.85%。上述序列被划分为1359个条形码索引编号（Barcode index numbers, BINs），其中1344个BIN仅包含隶属于单个当前已确认物种的标本。795个案例中，BIN归属与已知物种完全匹配；另有197个物种被划归至2个或更多BIN（总计涉及556个BIN）。另有26个物种出现BIN合并现象，或同时存在合并与拆分情况。物种的分析标本数量与其BIN数量仅呈现微弱相关性，但有3个物种为明显异常值，其标本被划分至11至22个BIN中。尽管所有BIN拆分事件均需开展进一步研究以明确所涉类群的分类地位，但DNA条形码成功区分了1018个物种中的98%。本次调查保守发现16个科学新物种、52个加拿大新记录物种，以及426个物种的分布范围得到大幅扩展。若本研究中检测到的绝大多数BIN拆分均对应隐存分类单元，则加拿大蜘蛛的真实物种数量可能比当前认知高出30%至50%。