That's easy....they are all Lampropeltis triangulum.
Oh wait,.. you mean which subspecies. LOL
Actually, milksnakes in captivity are messed up. We have determined the phenotype of most milksnake subspecies in captivity after years of inbreeding of lineages with little good locality data from the start.
So, for example, as common as Hondurans are in captivity, most of them look about the same from years of breeding to remove black tipping, increase orange in bands, etc. They look very little like the wild caught Hondurans that used to appear in the US 15 years ago. Therefore, most people probably wouldn't recognize many wild caught hondurensis as such.
When you start comparing Nelson's and Sinaloan milks, they lines get even blurrier.
Frankly, without locality data, it can be really tough to assign many central american milks to subspecies.
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Chris Harrison