Hi, Brett.
Just call me slow-poke, but here's my 2 cents worth.
First, since being involved mainly with Asian ratsnakes since 1988, I have to say I've been adamant about not crossing localities, let alone subspecies, species, or genera. There's just too much we don't know about the Asians and they're too rare in most cases in the hobby to waste the known stock we have. For instance: the Dione's Ratsnakes (Steppes Rats) have a humungous range and no subspecies have been named. For me to cross my original Ukrainian, Chinese, and South Korean Dione's Rats would have meant losing the genes and the integrity of what those snakes represented. I've since just kept the South Koreans which I think will eventually be named a separate subspecies, at least, and possibly even a separate species from the Chinese dione.
I haven't kept American ratsnakes too much, but have kept a few species, mainly Pantherophis (Elaphe) guttata. While some subspecies may cross with other subspecies in a species (group), they mainly do that where the two subspecies come into contact. Sure, most genes flow throughout the species, but why not maintain the integrity of the "look" you want. Recently a black rat was posted from New Jersey, I think. It was an awesome snake. The way I look at it is why cross two nice animals to make a mutt. But then I'm not perfect, let me tell you about the mutts I'm making...hahahah.
Arguably the most widely bred and crossed and created snake species in the world is the "corn" snake. Some folks think the Great Plains Ratsnake is a separate species, but for the sake of argument here let's call it a subspecies of the corn snake, P. guttata. Now in my collection we have had quite a number of corns in the past and they have been mixed together a lot, mostly because I didn't have locality info on them anyway. Well, anyway, I sold off most of them in the last few years and ended up with one hypo corn (mutt) and one Brazos Island Ratsnake, P. g. meahllmorum. Naturally, I bred them to see what the offspring would look like. I don't see any problem with this because this species is so domesticated to begin with. I'll let it rest at that.
Ok, then here's what happened next in the guttata department. A couple years ago I bought a CB pair of P. g. "intermontana", Western Great Plains Ratsnakes. Very neat snakes and very distinct. I don't want to lose the "look", so I'll keep this morph "pure". I also bought another pair of Brazos Island Ratsnakes...different subspecies of guttata/emoryi. This is a very interesting morph also and I plan to keep this morph "pure".
So, here's my final plan, to make my main point. I'm going to breed the "intermontana" to the hypo x Brazos cross to get the hardy genes and smaller snake genes into my "mutt" line. Then I'm going to breed the Brazos in again and possibly another mutation besides the "hypomelanism".
The point: folks are going to do what they want to do and so what. None of these snakes should ever be put back into the wild anyway. Their genes are lost to the species, so it doesn't much matter what happens to them. They are pets. Not that they are just here for our pleasure, but they are dependent on us, and they should be treated with respect. They are dependent on our care to survive.
Some of them are going to be pure because some people like the pure look and want to work with just that form. They try to keep a certain locality in order to get the look they want. Other snakes are going to be crosses, because some folks want a designer corn...LOL. I like both when it comes to corns, but man don't mess with my Asian Ratsnakes.
PS: I don't condone crossing species to make hybrids, but I would like to cross a Eurasian ratsnake with an American ratsnake to see what happens, if it would produce anything. And, no, I don't think all snakes that can cross and make babies should be in the same species, let alone genus. I think crossing species is pretty unnatural, and I don't buy the idea this happens in nature, except rarely bt. very close species.
PBS: I think the corn snake discussion is worth pursuing. Please add to that if you see fit. Thanks,
TC
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Ratsnake Haven: Elaphe dione, bimaculata, mandarina, conspicillata, porphyracea coxi, t. taeniura, situla, emoryi; Lampropeltis zonata, and mexicana. 