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What is the difference between a Rat Snake and a Corn Snake? Or is there a difference beyond the scientific breakdown into the family/genus/species/sub-species?

I am a novice to the field of snakes, and this untrained eye can't tell the difference, yet.

Thanks in advance,

Marcus

89 Tarantulas
1 trapdoor spider
1 black widow
1 black hole spider
5 scorpions
1 Oketee Corn Snake
1 Ghost Corn Snake
1 Ball Python
2 dogs
1 lizard
3 rats (pets)
3 gerbils (breeders)
And a partridge in a pear tree

Corn snakes are a type of North American rat snake. So, really, there is no difference.
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Peter: It's OK, I'll handle it. I read a book about something like this.
Brian: Are you sure it was a book? Are you sure it wasn't NOTHING?

The corn snake is a subspecies of the Elaphe (Pantherophis for those of you keeping up on the change in taxonomy). And is in the rat snake family.

For example, the common black rat is Elaphe Obsoleta Obsoleta,
the gray rat is the Elaphe Obsoleta Spiloides and the corn is Elaphe Guttata Guttata.

Hope this helps
Brian

If you look at a cross-section of the cornsnake's body, you will notice that it is shaped like a loaf of bread. This is the same for the North American ratsnakes. Apparently this shape is better for climbing than say the more rounded cross-section of a kingsnake or milksnake. The point is, cornsnakes are indeed ratsnakes, but have evolved characteristics that are slightly different than say black ratsnakes and transpecos ratsnakes (but they are all still ratsnakes.) I notice that cornsnakes seen to have a slightly pointier head shape than other ratsnakes.

So, if I'm following correctly, the Corn Snake is just a species of Rat Snake. Right? Now, are all Rat Snakes in North America Elaphae guttata guttata? Or are there other species of Elaphe here that only called Rat Snakes (by common name)?

..

So, if I'm following correctly, the Corn Snake is just a species of Rat Snake. Right? Now, are all Rat Snakes in North America Elaphae guttata guttata? Or are there other species of Elaphe here that only called Rat Snakes (by common name)?

Good luck
Brian

http://www.cnah.org/nameslist.asp?id=6

Thanks for the information!

Marcus

Unfortunately, the term ratsnake is a term that is applied to many different and unrelated snakes. It seems that in early herpetological descriptions, any snake that ate rodents and was at least partially arboreal became a type of ratsnake.

So the name ratsnake has been used in reference to snakes in the genus Elaphe, Bogertophis, Senticollis, Ptyas, Coluber, Gonyosoma, Spilotes, Drymarchon, etc., etc,. etc.......

While some of these snakes were certainly unrelated to each other, many were lumped together under the genus Elaphe. Until recently, there were species of Elaphe in Europe, Asia, and North America.

Now with the increase access to specimens from formerly remote areas and with modern systematic techniques, scientists are correcting these problems. One of the problems that has been corrected is that the North American "Ratsnakes" have been removed from the genus Elaphe and placed in three separate genera (Pantherophis, Senticollis, and Bogertophis). This is to show that they are not as closely related to the European Ratsnakes as was formerly believed.

The use of Pantherophis has been slow to take hold just as the use of the genus Nerodia was slow to replace the genus Natrix for north American Watersnakes. Many N.American biologists still used the genus Natrix ten years after it was replaced with Nerodia, mostly out of habit.

So technically, Cornsnakes are members of the genus Pantherophis. They are related to the other members of this genus (P. obsoleta, P. gloydi, P. vulpina, and P. flavirufa) but are a valid species of their own (P. guttata).

Within the species Pantherophis guttata, there are currently a few "accepted" subspecies (but these are being actively investigated and my change in the near future)
- Cornsnake - P. guttata guttata
- Great Plains Ratsnakes - P. guttata emoryi
- Southwestern Ratsnake - P. guttata meahllmorum
- (Kisatchie/Slowinski's Cornsnake - P. guttata slowinskii - a new subspecies not in wide use yet)
- (Intermontane Ratsnake - P. guttata intermontana - an old subspecies not recognized by most people anymore).

So Cornsnakes (or Red Ratsnakes, as they are often called) are "ratsnakes" in that they are members of the genus Pantherophis.

This issue is further confounded by the fact that there are other North American "Ratsnakes" that are in other genera (Trans-pecos Rats = Bogertophis and Green Rats = Senticollis) while there are snakes in the genus Pantherophis that aren't called ratsnakes at all (Elaphe vulpina and gloydi = Eastern and Western Foxsnakes).

This is why scientists (and many hobbyists) prefer to use scientific names!
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Chris Harrison

...he was beginning to realize he was the creature of a god that appreciated the discomfort of his worshippers - W. Somerset Maugham

Now with the change to Pantherophis, hasnt the rest of the genus sub-species name been changed as well?? I think I recall seeing them changed, but cant remember where. I think the Obsoleta was changed to Obsoletus; Guttata was changed to Guttatus; etc. I was trying to find where I had read this but man, with old age comes that silly thing called loss of memory!!

Is this change officially taken effect or is the "jury" still in? I know there were some arguments on the slowinskii as well.
Just curious.
Thanks
Brian

Brian,

You are correct that the specific epithet must agree with the gender of the genus name. This was the issue that changed Lampropeltis getulus to L. getula a few years back.

I don't know what gender Pantherophis is. If it is masculine or neuter, then I guess they will have to change the endings of the specific epithets to match, so they would be guttatus (or guttatum) etc., but I don't know what gender Pantherophis is so I couldn't give a definitive answer.

If it is masculine it would be P. guttatus, if it is neuter (like Masticophis), I guess it would be P. guttatum. I will let someone with more background in (latinized) Greek answer that question.

Another issue to consider here is the taxonomic status of P. obsoleta (um,us?). Since the publication of Burbrink's paper, there may need to be a total overhaul of that species group anyway. So it may turn out to be P. alleghaniensis and P. spiloides rather than obsoletus.
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Chris Harrison

...he was beginning to realize he was the creature of a god that appreciated the discomfort of his worshippers - W. Somerset Maugham

I guess Ill have to just wait and see what the experts come up with.
Appreciate it!
Brian

Very informative.

I'm gonna have to save and read your reply a couple of times so that it can soak in.

I personally prefer to use the scientific names just so that there isn't any confusion about what animal I'm talking about.

Thanks again!

Marcus