What’s a Spider? Designation of the Neotype for the First Animal Species Ever Described, Araneus angulatus Clerck 1757 (Araneae: Araneidae)

We designate a neotype for the Eurasian spider species Araneus angulatus Clerck, 1757, thereby fixing the objective application of the species name, the genus name Araneus Clerck 1757, the family name Araneidae Clerck 1757, and the superfamily name Araneoidea Clerck 1757. By etymology and arachnological tradition, it also unofficially fixes the application of the ordinal name Araneae Clerck 1757 and thus answers the uncontroversial question, “What’s a spider?” A. angulatus also happens to be historically the first animal species ever described because Clerck (1757) has priority over Linnaeus (1758). Neotype designation is justified for three reasons: the syntypes of A. angulatus are lost; “A. angulatus” contains significant COI sequence divergence, potentially representing intraspecific variation, misidentifications, or as many as four undescribed species; and, with the neotype anchored via a COI barcode to a reference genome, future researchers can use this species as the “exemplar spider” in analyses, knowing that their results will not be compromised in the future by nomenclatural changes. Because all 1757 Clerckian names are spiders, should the considerably less uncontroversial question ever arise, “What’s an animal?” one objective answer is, “It’s a spider, and probably the neotype of A. angulatus.”