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.