This is about Pantherophis, the ratsnakes endemic to the eastern regions of North America.
SSAR and CNAH substituted P. alleghaniensis for P. spiloides, and resurrected P. quadrivittatus.
For the eastern part of the USA we now have:
P. alleghaniensis — Central Ratsnake
P. quadrivittatus — Yellow Ratsnake
The geographic range of P. spiloides (Gray Ratsnake) extended further east and therefore overlapped with the locality of Holbrook’s type specimen (Coluber alleghaniensis, 1836) of P. alleghaniensis in Virginia. Thus, the former P. spiloides (Gray Ratsnake) becomes P. alleghaniensis, and the former P. alleghaniensis (Eastern Ratsnake) becomes P. quadrivittatus (Yellow Ratsnake) .
As I understand it, P. spiloides (Gray Ratsnake) is not a valid taxon anymore, and the species complex Eastern/Gray is no longer appropriate.
I don’t know what will happen with the ratsnakes along the Atlantic coast in a few of the southern states. When you look at the distribution map, it seems possible that a species complex Central/Yellow exists. The complex Eastern/Gray was used because there were two genetic lineages involved. It is unclear to me how this revision of the taxa solved the issue of Burbrink’s genetic lineages. Do we now have a single species (P. alleghaniensis) that represents a ‘hybrid’?
New SSAR name list (9th edition, published in March 2025):
https://ssarherps.org/publications/north-american-checklist/
https://cnah.org/taxon.aspx?taxon=Pantherophis_alleghaniensis