Ruthvens King or Mexican Milk?
 

I purchased this beautiful snake recently (first two photos). Sold to me as a Ruthvens King Snake. Then I saw this video from Snake Discovery, claiming that this snake (last photo) was a Mexican Milk Snake. They look almost exactly alike to me. My research shows a lot of variability in the appearance of each. Also, Their ranges overlap and I understand that they may hybridize, even in the wild. So, it may be very difficult to know which is which. So what is this snake? Ruthvens King Snake or Mexican Milk Snake? I was hoping to learn more about my new pet. Thank you.

Depending on the seller of the snake, you could have a hybrid. Something to keep in mind.

Otherwise, it looks as if the ventral scale count is the most divergent diagnostic feature of the two species -- L. ruthveni is 182-196, while the former L.t. annulata is 42-56.

Sources:

http://www.kingsnake.com/king/ruthveni/ruthveni.html
http://www.kingsnake.com/king/triangulum/annulata.html

How to count:

http://www.arod.com.au/arod/scale/

Ruthvens has been bred into so many other species over the decades that unless it is a verified locality wild caught, I would highly doubt it's "purity". Even looking at the pics you provided, based on the shape and pattern of the head, it looks to me that there might be some "mexicana" in it's heritage.

Matter of fact, I heard rumors a LONG time ago that the people doing a lot of the major hybridization in kings and milks would hatch out the babies and then segregate them by appearance, labeling them as whatever they appeared to be closest visually.

But you will probably never know. Any intentions of selling the animal and selling the offspring? If not, do you like the snake? For a pet, that is all that really matters. Of course, you would like to know, but unless you did a lot of digging to find the source of the animal concerning who produced it and could provide it's ancestry, I doubt you will have much success identifying it just by comparing photos.

By ventral scale count alone, she would be a Ruthvens King. She definitely has more than 56 scales. Much closer to 200. That is easy enough to see. Still not sure though. The banding on my snake is much wider than in the picture of the Ruthvens on the page you attached. The band width is more in line with the photo of the milk snake. I have also read that there is sometime a subtle lime green edging on the Ruthvens kings. My snake has no green edging. Thanks for your help.

She is just a pet, and I have no intention of breeding her. I am very happy with her attitude and her beauty. I was just wondering. I was told from the seller that she was a Ruthvens. The seller being a retail outlet, not a breeder. I have no reason to doubt the word of the seller. I just began to wonder when I saw a picture of one that looks exactly like mine that was called a Mexican Milk Snake.

I agree with Rich, and I think info like this is really interesting and relevant. Old-timers should write all this stuff down and publish a book, since all of this is going to be lost once everyone migrates to Facebook and info disappears whenever the wind changes.

Nonetheless, I sort of take 'is my animal X' questions to be 'is my animal what the hobby calls X' rather than as some genetically pure animal suitable to be a type specimen.

My question being, aside from old-timers, who would actually read the book, when they can simply google and then argue their opinions? Lol.

Add-on question: What is the correct nomenclature, King Snake and Milk Snake, or Kingsnake and Milksnake?

Most commonly used by herp folks is "kingsnake" and "milk snake", though I don't know why the difference.

Possibly because autocorrect will change milk snake to milk shake if the words are not separated.