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I've heard they are very simular, so now im just wondering what the differences are (ie: height, weight, temperment?)

>>I've heard they are very simular, so now im just wondering what the differences are (ie: height, weight, temperment?)

Corn snakes are a sub-species of the common rat snake, which makes them a rat snake!! The corn is not unlike many of the rat snakes of north america, many of the rat snakes have a mellow temperament. Just that the corn overall has the easiest temperament of the rat snakes.

As far as size goes, the corn is one of the smaller rat snakes, but can attain lengths of 6'. Average size is probably around 3.5 - 4.5'.

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Good luck and Happy Herping
Brian

Corn snakes are a sub-species of the common rat snake, which makes them a rat snake!!

Cornsnakes are ratsnakes because they are in the same genus as the common ratsnake. (They used to both be in the genus Elaphe, but now are both in the genus Pantherophis.)

There are several subspecies of the common rat snake, P. obsoleta (sensu lato, LOL)(Everglades, Yellow, Black, Gray, TX).
Likewise, there are several subspecies of cornsnake (P. guttata) (Cornsnake, Great Plains Rat, Southwestern Ratsnake).

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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

are all North American rats now Pantherophis or are there exceptions?

are Eurasian rats still elaphe?

why did they seperate elaphe and Pantherophis?

Is elaphe pronounced Ee-laugh-ae?
Other genus i don't know how to pronounce are thamnophis, agkistrodon, occipitomaculata (storeria), nerodia sipedon, opheodrys, drymarchon, nasicus (heterodon), pituophis melanoleucus, bogertophis subocularis, lampropeltis, micrurus and sistrurus.

Sorry to just dump a huge list of names on you but I learn mostly from books and would like to sound not quite so stupid in person.

Thank You
Cam Hanna

Elaphe is still a valid genus. In a recent paper, I think in 2002, the genus Elaphe was split into many new and resurrected genera, but the genus Elaphe survived to include the northern group of Eurasian ratsnakes, namely...E. schrencki, E. quatuorlineata, E. dione, E. bimaculata, E. carinata, and others. These splits are not automatically accepted by all scientists, however, and must stand the test of time. I still use "Elaphe" for most ratsnakes, because of this, and am waiting to see what happens in the scientific community. In other words, you can use the new genera or keep using Elaphe for all the ratsnakes until more is written about the changes.

BTW, not all American ratsnakes are in the genus Elaphe. For instance, you have Bogertophis and Senticolis, and some other genera which are debatable.

PS: There's supposed to be a new paper coming out soon from Vaughan, et. al, on the taxonomy of the Elaphe guttata complex. Hope we settle that and the Emory's ratsnakes become more clear in their relationships

TC

I don't believe this issue will ever be settled, Terry. Scientists are not God, even though they might like to think they are. The splitting of genera has been going on since Linnaeus, and I doubt there will ever be an end to it. Whether an "expert" has an axe go grind or a name to make or, simply, a paper to write, they will keep on reclassifying ad nauseam. For the hobbyist's purpose, the old standby names serve quite well, even when speaking of such declassified subspecies as E.o. williamsi or L.t. yumensis. At least we know what the heck we're talking about, and who's to say definitively that we're wrong? Names serve to classify, but hobbyists need some kind of stable nomenclature to identify. If you note an anti-scientific bias in my words, you're right.

I don't automatically accept changes in taxonomy. I do tend to be kinda scientific, but I don't think changes in nomenclature should be made unless it makes relationships more clear. Although I welcomed Pantherophis at first, one of the problems is that the genus leaves out flavirufa, which I can't understand. Also, there's the fact that the American ratsnakes are very closely related to the Eurasian ratsnakes and we know a Eurasian rat is the ancestor. How do you show that connectedness if not by being in the same genus? The question is, "By recognizing Pantherophis, are we making relationships among the ratsnakes more clear?" I think that remains to be seen. I tend to stick with the common names for the most part when the scientific names are too argumentative. Just thought I'd throw this idea out there in case anyone's interested.

Later....TC.

PS: I actually think we need more studies to clear things up, show more genetic comparisons, and clarify the relationships better. I agree this will probably never end as it's part of the system

Also, there's the fact that the American ratsnakes are very closely related to the Eurasian ratsnakes and we know a Eurasian rat is the ancestor.

I have not read the recent ratsnake literature, but I believe the basis for the resurrection of Pantherophis was that the American Ratsnakes were actually more closely related to Pituophis and Lampropeltis than they were to European Elaphe, therefore they were separated.
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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

Chris, the most recent publication, Utiger, et. al. (2002), has all the American ratsnakes, including genera other than Elaphe, lumped together as closely related. That means Pantherophis, Bogertophis, Senticolis, Lampropeltis, Pituophis, Arizona, Rhinochelis, Cemophoris, etc. What's left of the "Elaphe", after the splitting of Old World Elaphe, are some of the Eurasian species which I mentioned. They are shown as a group as being like a sister group to the American genera in the weighted MP tree. It's true, all the American genera are supposedly more closely related to each other than to any Old World ratsnakes, but as I said they're like a sister group to the "Elaphe" group of Utiger, et. al. Their research shows the two groups are in a clade together with a common ancestor. Some other splits are questionable also, such as the removal of taeniura, moellendorffi, etc, from the Elaphe. My question is, "Is it necessary?" I don't think their research included enough outside clades/unrelated genera, and most snakes they sampled were closely related. I think more testing needs to be done and more thought put into which species need to be split. Different testing methods will probably yield different results, so we can't be sure, yet, that Utiger's proposals will hold up even in the scientific community.

My 10 cents

TC

>>why did they seperate elaphe and Pantherophis?

Not too many years ago, ALL ratsnakes were in the genus Elaphe. Most people agreed that this was not a very good taxonomic arrangement (they weren't all related to each other) and the genus began to break up. Bogertophis, Senticollis, Gonyosoma were the first to go and those splits have been widely accepted. Now that the north american Elaphe have been put in Pantherophis, I suspect that will be accepted as well (even though many people don't "like" the name, they agree that N. American rats should be separated).

Now my egocentric pronunciation guides. I base this on the way I and others I know pronounce these names. I originally pronounced them in "correct" latin but found that I was almost alone and was soon "corrected".

(The capitalized syllable is where you put the emphasis. I don't know how to use the real diacritical marks, and it is more fun to try to type them out this way anyway!)

Elaphe = ee - LAY - fee

"Other genus i don't know how to pronounce are"
Since I am in correcting mode, the plural of genus is genera.

thamnophis = tham - NO - fis (like the words am, no, and fist)
agkistrodon = ag - KIS - troh - don
occipitomaculata = ok - SIP - ih - toe - MA - q - lay - tah
nerodia = neh - ROW - d - ah
sipedon = SIP - eh - don (like the words sip, a, and don)
opheodrys = O - fee - o - drees (like the words oh, fee, oh, and trees)
drymarchon = dry - MARK - on
nasicus = NAY - zik - uhs
pituophis = pit - you - OWE - fis
melanoleucus = meh - lahn - o - LEW - cuhs (like the words Mel, Ann, oh, Luke, and us)
bogertophis = BO - gert - o - fis (bo like beau)
subocularis = sub - ock - q - LEH - rihs
lampropeltis = lamp - pro - PELT - tihs
micrurus = my - CREW - rus
sistrurus = sis - TRUE - rus
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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

Oh Thank You, Thank You, Thank You

Years of agony have been put to rest.

...but. I guess you knew that was coming I took Greek for three years and taught Latin. Here are the ways some of these names should be pronounced:

Tham naw fiss
Ang kiss tra don
Ox cipita mah cu lahtah
Oh fee ah dris
Nah sih cus
Pit two ah fis
Sub ah cu lah ris
Mik cru ris

These are the correct Greek pronunciations of the generic names. Of course, specific and subspecific names are always in Latin. However, I doubt that even the renowned scientists that use these names pronounce them correctly.

Cheers!

Scientists are not God, even though they might like to think they are. The splitting of genera has been going on since Linnaeus, and I doubt there will ever be an end to it.

What changes is the scientific rationale behind the classification system. Linne's classification was set up to define the type of each species that was most "perfect". Modern classifications are set up to reflect evolutionary relationships between organisms. Therefore, as we learn more, we change our taxonomy to reflect the current understanding of the relationships. To do otherwise would be to acknowledge and tolerate ignorance within the system.

Whether an "expert" has an axe go grind or a name to make or, simply, a paper to write, they will keep on reclassifying ad nauseam.

I have, one more than one occasion, heard someone say that hobbyists use the classification that makes them the most money. They are only interested in splitting things so that they can sell their morph as a taxonomic identity which makes it more financially valuable to them. Its all about the money to the hobbyist. They don't really care about the relationships.

You are probably thinking this is an unfair generalization based on a skewed perception of a group of people that they know very little about. I agree. The same is true of your statement.

For the hobbyist's purpose, the old standby names serve quite
well,

Really? Do you still call watersnakes Natrix? Do you still use Lampropeltis doliata? Ophiobolus sayi? Which set of old "standby" names are are you referring to?

even when speaking of such declassified subspecies as E.o. williamsi or L.t. yumensis. At least we know what the heck we're talking about, and who's to say definitively that we're wrong? Names serve to classify, but hobbyists need some kind of stable nomenclature to identify.

Isn't that the purpose of common names? Can't you just call it an "blair's morph" gray-banded king, or do you need it to be called Lampropeltis alterna blairi? What about Lampropeltis californiae boylii? I bet in this case you are OK with just calling it a Banded Cal King.

Scientific names are NOT just labels. The binomial system is set up deliberately to reflect the phylogenetic relationships between the taxa. If not, what is the point of putting milksnakes and kingsnakes in the same genus?

If new evidence suggests that new world ratsnakes are related to old world ratsnakes do you think we should still maintain a nomenclatural system that implies that they are?

No one is telling you you can't still call all of them ratsnakes. Common names are good at maintaining those old relationships, even after data has shown that the relationship isn't there. I have no problem with that. I still call them Yuma Kings, I just don't use the subspecific name yumensis. I have no problem with someone using the name Gulf Hammock Ratsnake.

Hobbyists want names to be able to differentiate between recognizable morphs of animals. That is a perfectly legitimate purpose for a system of nomenclature. That is what our system of common names does. But that is not the function of our system of scientific nomenclature.

Maybe the two systems aren't compatible? I have no problem with a common name applying to many scientific taxa (Slimy Salamander) or representing a population which isn't taxonomically distinct under the scientific system (South Florida Kingsnake).
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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

If new evidence suggests that new world ratsnakes are NOT related to old world ratsnakes do you think we should still maintain a nomenclatural system that implies that they are?
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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

Excellent point and well-said, Chris. I am by no means a biologist. I teach high school English, but I do have certain biases when it comes to biology and the scientific classification of animals. You're right that Linnaeus started his classifications from a diffrent premise from current-day biologists/herpetologists. I'm not an evolutionist. I'm a creationist, and if the scientific community reclassifies animals simply to reinforce their world view that the world around us and everything that exists in it is just a happy accident, I take issue. Are we splitting Elaphe because scientists are trying to fit species into an evolutionary schema, or are they splitting it because there are actual biological/morphological differences betwixt the two? I look at the archetypal rat snake head, for example, and see very little difference between a four-lined ratsnake and E. obsoleta. I'm talking about scalation and bone structure. Of course, I don't have access to holotypes that I can examine meticulously and, therefore, must defer to the authorities' conclusions. However, as a creationist I do not accept the premise that all life comes from a single ancestor, but I'm not averse to the probability that life forms diverged into different categories within genera/species over the millenia.

I'm not going to argue beliefs here, but will talk about how Utiger, et.al.(2002) came to their conclusions, so there's some clarification there. It was basically a study of DNA/genetic material, I believe. I don't think they used much in the way of morphological characteristics or other biological means to do their proposal. The Old World Elaphe do have an "intrapulmonary bronchus" to one length or another, and the New World Elaphe seem to be lacking that organ for the most part. Other than that they look a lot a like, I agree. My question would be, "Are their genetic differences enough to reclassify them?" Morphology alone certainly isn't enough, all that was done in previous studies, and I don't know if any taxonomist is willing to look at something like behavioral differences in their proposals. One more thing that they looked at I think was the differences in hemipenes. I believe the structures of the New World rats have some similarities and are different from Old World. My choice of words would be, more evolved.

Hope this helps a little. Cheers....TC.

But wasn't the study done on mtDNA and not the DNA of their chromosomes? I still think that morphology is the best tool that we have for classification for the near future.

Yes it was mitochondrial dna. Should've made that more clear.

Seems the thing of the future is chemical analysis, dna testing. It's supposed to be the most accurate tool we have now to show relationships or how related species are to each other. I think it has a lot of potential, but also feel that many improvements in methods, etc, will take place through the years.

One of the problems we seem to have with this type testing is that the common lay person, or hobbyists in our case, have a hard time understanding what's going on with this chemical analysis stuff. What you can't see and relate to very well can be very annoying, and many might doubt the accuracy of such methods. I can surely sympathize, as I've been there, but it does seem to be here to stay, so try to understand I will.

Later....TC.

Thanks, Terry. You can't argue with DNA evidence unless you're Johnny Cochran. As for the hemipenes, my choice of words would be "different." Ciao.

Thanks for the help!! I knew what I wanted to say but just didnt word it right!! LOL

Sorry for the confusion.

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Good luck and Happy Herping
Brian