Probing planetary biodiversity with DNA barcodes: The Noctuoidea of North America.By Zahiri R., J.D. Lafontaine, B.C. Schmidt, J.R. deWaard, E.V. Zakharov, P.D.N. Hebert
This work details the progress with DNA barcoding of the Noctuoidea of North America. It discusses the effectiveness of barcoding and provides a list of species for which barcoding does not distinguish species.
Available at PLOS ONE here
For a spreadsheet of species which share barcodes with at least one other species, see S8 Table under "Supporting information" here
(scroll down a bit past half way).
Abstract: This study reports the assembly of a DNA barcode reference library for species in the lepidopteran superfamily Noctuoidea from Canada and the USA.