In the new Pohl & Nanz Checklist of North American Lepidoptera (2023, p. 278, App. I), Chris Schmidt (@neoarctia) synonymizes coturnix and occidentalis under P. americana. The Appendix entry for this genus offers a detailed summary of the complicated evidence for and against previous species limits.
Pohl, G. R., & Nanz, S. R. (Eds.). (2023). Annotated taxonomic checklist of the Lepidoptera of North America, North of Mexico. Wedge Entomological Research Foundation.
Unintended disagreements occur when a parent (B) is
thinned by swapping a child (E) to another part of the
taxonomic tree, resulting in existing IDs of the parent being interpreted
as disagreements with existing IDs of the swapped child.
Identification
ID 2 of taxon E will be an unintended disagreement with ID 1 of taxon B after the taxon swap
If thinning a parent results in more than 10 unintended disagreements, you
should split the parent after swapping the child to replace existing IDs
of the parent (B) with IDs that don't disagree.