Thank you for your question. I was not familiar with this species, so I sent your photographs to a kingsnake breeder. The common name of your snake is the Nuevo Leon Kingsnake. It is also known as the Variable Kingsnake. There seem to be quite a few versions of scientific name for this species. I am not a taxonomist, so I can't sort them all out, however, Lampropeltis mexicana thayeri leonis seems to be pretty common.
This snake has an average length of approximately 3 feet, and a maximum length of approximately 3.5 feet. They feed primarily on rodents and lizards.
Here's a link to a care sheet published by Reptiles Magazine that you may find useful:
I hope this answers your question, and thank you for contacting Ask an Expert.