Introduced from Europe to the Pacific Northwest.(1) (Our voucher specimen came from Quebec, so it may have been introduced elsewhere.)
Herbst, J.F.W. 1799. "Forsetzung der Naturgeschichte der Insectengattung Opilio." In: Herbst, J.F.W., Natursystem der ungeflügelten Insekten, vol. 3 [of 4]. Gottlieb August Lange, Berlin, iv + 30 pp., plates 6–10. [online PDF here, original description page 9]
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