Reptile & Amphibian Forums

I'd be interested in chatting with folks about this snake and scheduling possible trips to search for them in the field either now or in the spring. I am after cb offspring as well. post a note here or send me an email: lateralis@aol.com
Cheers
BRett

I love those guys.
I'm waiting for the cbs to be easier to work with. His name escapes me for the moment, but the head herpetologist at the San Antonio Zoo breeds them. You may want to contact him.
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...and I think to myself, "What a wonderful world."

His name is Alan Kardon. I had 1.2 from him and worked with them for about three yrs. Didn't have too much trouble except w/brumation. They were CH from Chihuahuan stock. I sold them off this past summer to make room for more Asian species.

Actually I hunt for green rats every summer while in s.e. AZ on vacation. I've only found one so far, but plan to see lots more once we retire there in about five more yrs. They are a very interesting snake, but not for everyone, as they as a little high strung, kinda racer-like.

It a recent discussion of ratsnake taxonomy, it was decided that not enough is known about Senticolis, yet, to be sure if it's in the Lampropeltini w/other genera like Pantherophis and Lampropeltis, or if it is really closer to the racers. I'm sure we'll hear more in the future. In my opinion it's kind of in a class of its own and may represent a different ancestor/Asian invader than that of the rest of the American colubrids.

>>I love those guys.
>>I'm waiting for the cbs to be easier to work with. His name escapes me for the moment, but the head herpetologist at the San Antonio Zoo breeds them. You may want to contact him.
>>-----
>>...and I think to myself, "What a wonderful world."

Herndon Dowling published a paper on this species in 1987. Fig. 2 shows the hemipenial morphology of American and Asian species of Elaphe. E. obsoleta and E. taeniura have very similar hemipenis morphologies. In comparison, the hemipenis of Senticolis triaspis does not look like either species. That suggests E. obsoleta may be more closely related to E. taeniura than either of them is to Senticolis. Senticolis also has a long tail, like the racers. The next clue of Senticolis' relationship came from Keogh (1996), who shows that Senticolis does not have an intrapulmonary bronchus, which is possessed by Lampropeltis, Arizona, Pituophis, Cemophora, Bogertophis, Rhinocheilus, New World species of Elaphe and Stilosoma. That means all of these species are more closely related to each other than any of them is to Senticolis. All of the species that possess the intrapulmonary bronchus probably descended from a single common ancestor that came from Eurasia. This theory is reinforced by the similarities in hemipenial structure among them and Eurasian species of Elaphe, such as E. taeniura, E. moellendorfi, and E. quatorlineata. More recent DNA data also confirm this relationship. There are some authors who seem to have the predetermined idea that Senticolis is more closely related to New World species of Elaphe than to the Old World species. Accordingly they prefer trees that show this relationship, even though the statistical support for that particular node is poor, a bootstrap value of 30 for example in Utiger et al.'s tree. Most likely Senticolis lies outside of the group that include the New and Old World species of Elaphe and the Lampropeltini. Since the closest relatives of ratsnakes and their descendants are the racers, Senticolis is probably a racer, not a ratsnake.

Interesting stuff. I wouldn't mind having a couple more papers. I appreciate the one you already sent to me. Ever since I got into the ratsnakes in the late 80's I've wished I had the Dowling paper, and I'd also like to see/study the Keogh paper. Any chance you could send me a PDF file or link to these? I'd find them on my own if I knew where to look.

You said:

"There are some authors who seem to have the predetermined idea that Senticolis is more closely related to New World species of Elaphe than to the Old World species. Accordingly they prefer trees that show this relationship, even though the statistical support for that particular node is poor, a bootstrap value of 30 for example in Utiger et al.'s tree. Most likely Senticolis lies outside of the group that include the New and Old World species of Elaphe and the Lampropeltini. Since the closest relatives of ratsnakes and their descendants are the racers, Senticolis is probably a racer, not a ratsnake."

My response:

I agree that Senticolis is probably not most closely related to the New World ratsnakes (Lampropeltini), but I don't know how much of a racer it is. First, I like a taeniura/moellendorffi type ancestor for the Old World Elaphe, and that might work as an ancestor for Senticolis too. The scutellation on Senticolis is quite different from the normal racer. Also, some other features, like the head shape, are quite ratsnake-like. Senticolis is a pretty strong constrictor too. Elaphe taeniura is a racer-like ratsnake, like Senticolis. The hemipenes morphology might not be very similar, but the Senticolis ancestor is likely a different and older species than taeniura, and related in other ways. Many of the most basal species have both ratsnake and racer type characters. I believe a basal type Asian ancestor of the ratsnakes was a very early invader of the New World (maybe late Oligocene/early Miocene) and gave rise to Senticolis or similar type ratsnake.

I have to go out of town this weekend and will return Sunday night. Maybe I'll see more posts on this thread then. Later...TC.

Terry,
I find this interesting about Senticolis possibly being more related to racers than to ratsnakes. This could be similiar to when Sphalerosophis was thought to be a rat, and is now considered a racer.

Yep, you're right...Spalerosophis is another one of those racer-ratsnakes...imo, pretty closely related to the Asian ratsnakes. You have Western green rats...what do you think of them? TC.

Terry,
Yep, when I had Spalerosophis d. atriceps, they acted more like Pituophis than either racers or rats. As for triaspis, both my w/c's and c/b's act the same...a little more nervous than what you would give to any other North American ratsnake. I'm no taxonomist, and my observations are based on captive conditions, artifical at best..but if I were to give an analogy,I would say that Senticolis is to Pantherophis/Elaphe as Rhinocheilus is to Lampropeltis. Just my .02.
Best...
Jim

Jim,

You've got more experience than most with this species. My goal is to see as many as I can in the wild. I think that helps one to understand the nature of the species. I've been looking at E. massasaugas for a long time and think I know them pretty well, but still learn new things every year. I'll probably never know everything about them.

Last summer I saw my first pyromelana in the wild. What an experience. Some of the details include...an aberrant pattern; much quicker than expected movements; and a capture time of 11:30 pm. I think I'll know more about triaspis once I start catching up to you in number of sightings, lol.

As for the taxonomy, not many of us are college educated taxonomists. I just play at it myself because I want to learn more about the snakes I keep. I think if I had been educated as a taxonomist, I wouldn't have been able to pursue what I care about the most, however.

Anyway, I appreciate your comments. The info about Spalerosophis helps. Hopefully, our understandings of the ratsnakes will keep getting better and better with time.

Take care....TC.

Jim, you said: "I'm no taxonomist, and my observations are based on captive conditions, artifical at best..but if I were to give an analogy,I would say that Senticolis is to Pantherophis/Elaphe as Rhinocheilus is to Lampropeltis."

This is an interesting analogy. Let me just add that there are other analogies, especially in s.e. Asia, where species, or groups of ratsnakes exist peripherally to the Elaphe (or Orthriophis..new genus via Utiger et al.), that seem to fit the same pattern. One example is the Coelognathus (radiatus, subradiatus, helena, flavolineata, etc.), which have recently been said to be closer to racers than ratsnakes (Utiger et al., and others).

Senticolis might be closer to the Coelognathus than to Elaphe or any of the Lampropeltini. As a matter of fact, there are other species/groups that might be related to Coelognathus too, such as your Spalerosophis, or even Zamenis (longissimus, situla, etc, previously Elaphe). I think there needs to be more work done on comparing various species of ratsnakes/racers. The final verdict isn't in, yet.

BTW, I think the taeniura/moellendorffi group should stay in the Elaphe, at least until there's more convincing data to separate them. My .02 cents TC.

You wrote:
One example is the Coelognathus (radiatus, subradiatus, helena, flavolineata, etc.), which have recently been said to be closer to racers than ratsnakes (Utiger et al., and others).

My response:
Unfortunately, Utiger et al. did not include any of these species in their analysis of their ratsnakes. Therefore there is no data to show whether these species are part of the ratsnake clade sensu Lopez and Maxson. We do not know whether these species are in fact closer to the racers or the ratsnakes.

You wrote:
I think there needs to be more work done on comparing various species of ratsnakes/racers. The final verdict isn't in, yet.

My response:
I agree. One wonders why Utiger et al. fail to include these species in their study. But the species they do study do form a clade. Since the species previously classified in the genus Elaphe do not form a polyphyletic group, I disagree with their decision to splinter it into nearly a dozen poorly defined or undefinable genera. Putting Elaphe flavirufa and E. obsoleta in two different genera is particularly ill advised. They are obviously closely related species which share a recent common ancestor and they are both descended from the same species of Elaphe which migrated to the New World from the Old World. There is no good reason to split these two species into different genera. Senticolis appears to be outside of the species of Elaphe (both Old World and New). From what I read about Senticolis, it may actually be closer to the racers than Elaphe radiata. Dowling and Fries comment that Senticolis is not apparently close to any known species of colubrine snakes. That means they think that E. radiata is closer to E. obsoleta, than either one of them is to Senticolis. Yet Utiger et al. show that Senticolis is closer to E. obsoleta than E. mandarina is to E. obsoleta! This part of the tree is definitely problematic, especially in view of the low bootstrap value for this node (30).

I wrote:
>>One example is the Coelognathus (radiatus, subradiatus, helena, flavolineata, etc.), which have recently been said to be closer to racers than ratsnakes (Utiger et al., and others).
>>
You wrote:
>>Unfortunately, Utiger et al. did not include any of these species in their analysis of their ratsnakes. Therefore there is no data to show whether these species are part of the ratsnake clade sensu Lopez and Maxson. We do not know whether these species are in fact closer to the racers or the ratsnakes.
>>
My response:
Yes, it's unfortunate, but Coelognathus was removed from the Elaphe by Helfenberger in '01, so they were consider ratsnakes by many taxonomists before that. They do have many characteristics of both ratsnakes and racers, so much work needs to be done in this area.

I wrote:
>>I think there needs to be more work done on comparing various species of ratsnakes/racers. The final verdict isn't in, yet.
>>
You wrote:
>>I agree. One wonders why Utiger et al. fail to include these species in their study. But the species they do study do form a clade. Since the species previously classified in the genus Elaphe do not form a polyphyletic group, I disagree with their decision to splinter it into nearly a dozen poorly defined or undefinable genera. Putting Elaphe flavirufa and E. obsoleta in two different genera is particularly ill advised. They are obviously closely related species which share a recent common ancestor and they are both descended from the same species of Elaphe which migrated to the New World from the Old World. There is no good reason to split these two species into different genera. Senticolis appears to be outside of the species of Elaphe (both Old World and New). From what I read about Senticolis, it may actually be closer to the racers than Elaphe radiata. Dowling and Fries comment that Senticolis is not apparently close to any known species of colubrine snakes. That means they think that E. radiata is closer to E. obsoleta, than either one of them is to Senticolis. Yet Utiger et al. show that Senticolis is closer to E. obsoleta than E. mandarina is to E. obsoleta! This part of the tree is definitely problematic, especially in view of the low bootstrap value for this node (30).
>>

My response:
I agree that this part of the tree, dealing w/Senticolis, is problematic. As a matter of fact, I agree with a lot of what you're saying, BUT, whether the genus is polyphyletic, or not, doesn't necessarilly mean that there can't be new genera. The Elaphe was already paraphyletic. It is still paraphyletic, is easier to work with, and is easier to understand relationships. The ancestors are still questionable, and may always be.

I agree that flavirufa should have stayed in the with the rest of the Pantherophis, but agree that Pantherophis is a good genus. I'm sure Utiger et al, think that their data on dna analysis justifies removing flavirufa, but I also think that this data is subjective and we can make what we want of it. We still need to use other characteristics, including the morphological ones.

I think that Senticolis is somewhat related to Bogertophis and flavirufa, that they have some characteristics in common, and probably share a common ancestor. Senticolis is probably close to the ancestor for the New World Elaphe group. On the other hand, it may turn out that there is more than one ancestor. Lampropeltis could have an ancestor different from the New World Elaphe ancestor, also, as well as Senticolis.

You wrote:
Yes, it's unfortunate, but Coelognathus was removed from the Elaphe by Helfenberger in '01, so they were consider ratsnakes by many taxonomists before that. They do have many characteristics of both ratsnakes and racers, so much work needs to be done in this area.

My response:
It is especially unfortunate because the mtDNA data would have provided a test for the validity of the genus Coelognathus. Conspiracy theorists would charge Helfenberger with protecting his own earlier proposal from scrutiny by deliberately excluding these species from the later study. Whatever the reason, the validity of Coelognathus must await another study. Some of Helfenberger's earlier conclusions are contradicted by Utiger et al., therefore there is a good chance mtDNA data may show that Coelognathus is an invalid genus. From what I read, it is a conservative group of ratsnakes that have "evolved" slowly. If that is the case, there is a good chance that some members are closer to some ratsnakes and others to another group of ratsnakes.

You wrote:
I agree with a lot of what you're saying, BUT, whether the genus is polyphyletic, or not, doesn't necessarilly mean that there can't be new genera. The Elaphe was already paraphyletic. It is still paraphyletic, is easier to work with, and is easier to understand relationships. The ancestors are still questionable, and may always be.

My response:
May be you won't be able to understand this, but what Utiger et al. are doing is to classify the snakes in their study to match their tree exactly. That means a slightly different tree will require a wholesale reclassification of these snakes again. A different tree can also result if they had included Coelognathus. Or it can result if different types of characters are used. Since there are problems with their tree, their classification is also problematic since it is based so rigidly on that tree. Nevertheless, many people, including, alas, some professional herpetologists, are accepting their proposal blindly.

New genera are justified for two reasons: polyphyly and morphological disparity. I took great pains to show that there is no polyphyly. That means the only justification for splitting Elaphe is morphological disparity. Utiger et al. do not say anything about morphological disparity. They do not distinguish the genera they resurrect and erect in terms of morphological disparity. They merely chop the tree up into different sections and give each section a different genus name. The problem is that if someone finds a new species, they would not be able to tell in which genus it should be placed. What they have done does not make it easier to understand relationships, especially since the relationships among the genera they recognize is largely unresolved.

You wrote:
I agree that flavirufa should have stayed in the with the rest of the Pantherophis, but agree that Pantherophis is a good genus. I'm sure Utiger et al, think that their data on dna analysis justifies removing flavirufa, but I also think that this data is subjective and we can make what we want of it.
We still need to use other characteristics, including the morphological ones.

My response:
If you agree that flavirufa does not deserve to be split from Pantherophis, then you understand why I believe E. obsoleta should not be removed from Elaphe. There is no difference morphologically between Pantherophis and Pseudelaphe, and there is also no difference between Pantherophis and Elaphe. In fact, there is no difference between any of the genera they recognize and Elaphe. That is why Utiger et al. do not even try to tell us what difference there is.

You wrote:
I think that Senticolis is somewhat related to Bogertophis and flavirufa, that they have some characteristics in common, and probably share a common ancestor. Senticolis is probably close to
the ancestor for the New World Elaphe group. On the other hand, it may turn out that there is more than one ancestor. Lampropeltis could have an ancestor different from the New World Elaphe ancestor, also, as well as Senticolis.

My response:
That is not likely. I went to the library to dig up data on the intrapulmonary bronchus. Senticolis has a right bronchus that is quite similar to those of the racers (2.3% of the length of the right lung). New World species of Elaphe average around 11%. Lampropeltis and all other species of the Lampropeltini have a right bronchus that range from 12-91%. Even Bogertophis has a right bronchus that are 14-19% of the right lung. Senticolis clearly is descended from a different ancestor than these snakes because of its short bronchus. Besides, the hemipenis of Lampropeltis is a close match of that of Elaphe obsoleta. This cannot be an accident. They are obviously closely related. This relationship has also been confirmed by many different types of moelcular data. OTOH, the hemipenis of Senticolis does not resemble that of Lampropeltis, Bogertophis, Elaphe obsoleta or any Old World species of Elaphe. It is most likely a racer that has converged upon the ratsnakes morphologically. There is really no evidence that it is part of the Lampropeltini.

Can't find the paper by Helfenberger resurrecting this genus for Elaphe radiata, E. erythrura, E. flavolineata, E. helena, E. radiata, and E. subradiata, which was published as a suppliment in the Russian Journal of Herpetology. So I have to rely on a web page for the info on the findings. Helfenberger finds, according to this web page, that E. mandarina is part of the moellendorffi-group. Utiger et al. find that E. rufodorsata is closer to E. moellendorffi than is E. mandarina. Helfenberger also finds that E. conspicillata belongs to the "porphyracea-group" but Utiger et al. shows E. conspicillata as sister taxon to E. mandarina with strong statistical support (100%). Helfenberger finds a "climacophora-group" which includes E. climacophora and E. bimaculata but Utiger et al. finds that E. climacophora is actually part of the E. carinata group and E. bimaculata is closer to E. dione. In sum, Helfenberger's results contradict those of Utiger et al. on the placements of many different taxa. Therefore it is premature to accept Coelognathus as a valid genus. It is unfortunate that Utiger et al. did not include the species of Coelognathus in their study. Helfenberger does indicate that Coelognathus and Gonyosoma show affinities to the E. moellendorfii group. Since Gonyosoma has been shown to be more closely related to Coluber than it is to Elaphe by Lopez and Maxson, this is another weird result of the Helfenberger paper, which is based on morphological characters. It shows that he is unable to distinguish some convergent characters from shared derived characters. It looks more and more like Coelognathus is actually an invalid genus. Its members are probably closer to other species of Elaphe than to the racers, contra Helfenberger's claim. E. mandarina and E. conspicillata appears to be the most basal members of the genus Elaphe, E. radiata, subradiata, helena and other species of "Coelognathus" may be a more derived group of species of Elaphe than E. mandarina. The taxonomic status of the genus Elaphe is chaotic to say the least because of the wholesale resurrection of old genera and erection of new genera.

You wrote:
>>Can't find the paper by Helfenberger resurrecting this genus for Elaphe radiata, E. erythrura, E. flavolineata, E. helena, E. radiata, and E. subradiata, which was published as a suppliment in the Russian Journal of Herpetology. So I have to rely on a web page for the info on the findings. Helfenberger finds, according to this web page, that E. mandarina is part of the moellendorffi-group. Utiger et al. find that E. rufodorsata is closer to E. moellendorffi than is E. mandarina. Helfenberger also finds that E. conspicillata belongs to the "porphyracea-group" but Utiger et al. shows E. conspicillata as sister taxon to E. mandarina with strong statistical support (100%). Helfenberger finds a "climacophora-group" which includes E. climacophora and E. bimaculata but Utiger et al. finds that E. climacophora is actually part of the E. carinata group and E. bimaculata is closer to E. dione. In sum, Helfenberger's results contradict those of Utiger et al. on the placements of many different taxa. Therefore it is premature to accept Coelognathus as a valid genus. It is unfortunate that Utiger et al. did not include the species of Coelognathus in their study. Helfenberger does indicate that Coelognathus and Gonyosoma show affinities to the E. moellendorfii group. Since Gonyosoma has been shown to be more closely related to Coluber than it is to Elaphe by Lopez and Maxson, this is another weird result of the Helfenberger paper, which is based on morphological characters. It shows that he is unable to distinguish some convergent characters from shared derived characters. It looks more and more like Coelognathus is actually an invalid genus. Its members are probably closer to other species of Elaphe than to the racers, contra Helfenberger's claim. E. mandarina and E. conspicillata appears to be the most basal members of the genus Elaphe, E. radiata, subradiata, helena and other species of "Coelognathus" may be a more derived group of species of Elaphe than E. mandarina. The taxonomic status of the genus Elaphe is chaotic to say the least because of the wholesale resurrection of old genera and erection of new genera.

My Response:
The taxonomic status of Elaphe is chaotic because it's always been chaotic. There might be mistakes being made, but that hopefully is on the way to progress in understanding the Elaphe. You don't seem to like any of the new genera, whereas, I like some of them and not others. I'm sure some folks will accept all or none.

Mandarina/conspicillata might be basal members of the Elaphe, but I hope you don't mean they have to be the ancestors for any other Elaphe. As a matter of fact, I think there's a possibility that Euprepiophis could be the ancestor of the genus Lampropeltis, and some other ancestor for the other New World Elaphe. Remembering the thing we did with analogies, Euprepiophis is to Old World Elaphe as Lampropeltis is to New World Elaphe.

It's possible that the Coelognathus species are closer to ratsnakes than racers, but I'm sure there are characteristics of both groups, and that ratsnakes and racers have a common ancestor far enough back in time. I think all the tropical ratsnakes have some characteristics in common, especially some morphological ones. Whether they are convergent or shared derived, I don't know for sure, but my guess is they share some kind of common ancestry. Coelognathus, Gonyosoma, and Elaphe all share certain characteristics, and they seem to have ratsnake, as well as racer charactersistics. So, what will more in depth dna testing tell us?

BTW, Utiger et al, did not remove prasina or frenata from the Elaphe, yet, for lack of sufficient data, but suggested they were closest to Gonyosoma, based on morphological characteristics. I agree. I think they should be placed in the Gonyosoma until we have further testing, and also think that the Vietnamese longnose ratsnake probably is closely allied with Gonyosoma, and should be tested again for possible removal from Rhynocophis.

I think there should be more in depth testing of Gonyosoma and others with the Elaphe and some racers. Lopez and Maxson used Coluber to compare to Gonyosoma, but needs to use several more genera to convince me. Actually, Coluber has several characteristics shared with the Elaphe, especially E. taeniura, and I think they could have retained some morphological ones from a common ancestor. Yes, they may be convergent too, but it's worth testing. It seems to me that Gonyosoma species have more ratsnake characteristics than racer, but we'll see.

Helfenberger may have messed up some in his '01 paper, but I believe his ideas were mostly proposals for dividing the Elaphe into related groups. I think he could have held off on creating new genera, but Coelognathus seems to have been well received. As a member of the Utiger et al. group '02, the stress has been put on dna testing to show relationships. This is better, but I feel there are still some problems, as already mentioned. Taking another example, let me say that climacophora could well have been derived from a taeniura/moellendorffi ancestor. I don't think this species should be in the "carinata" group. Carinata may well have been derived from the taeniura/moellendorffi group also, so could be allied with the Elaphe.

You wrote:
The taxonomic status of Elaphe is chaotic because it's always been chaotic. There might be mistakes being made, but that hopefully is on the way to progress in understanding the Elaphe. You don't seem to like any of the new genera, whereas, I like some of them and not others. I'm sure some folks will accept all or none.

My response:
Elaphe has never been chaotic. This genus has been around for a long time. Some species, such as triaspis, subocularis, rosaliae, and oxycephala have been found to belong to other genera and removed. The remainder form a natural, morphologically homogeneous group that is not polyphyletic. Therefore it should be retained as a single genus. You are correct that I do not like Utiger et al.’s proposal. I do not because it would obscure the close relationships between, say, Elaphe obsoleta, E. climacophora and E. scalaris if they are put in different genera.

You wrote:
Mandarina/conspicillata might be basal members of the Elaphe, but I hope you don't mean they have to be the ancestors for any other Elaphe. As a matter of fact, I think there's a possibility that Euprepiophis could be the ancestor of the genus Lampropeltis, and some other ancestor for the other New World Elaphe. Remembering the thing we did with analogies, Euprepiophis is to Old World Elaphe as Lampropeltis is to New World Elaphe.

My response:
E. mandarina and E. conspicillata probably retain many of the primitive characters for this genus, being the basal most members. They probably have unique characters of their own not found in other members. They could be ancestral to the other species but they cannot be ancestral to Lampropeltis or New World Elaphe directly. E. scalaris is probably the closest species to New World Elaphe, since both Lopez and Maxson and Utiger et al. independently find that E. scalaris is basal to New World Elaphe.

You wrote:
It's possible that the Coelognathus species are closer to ratsnakes than racers, but I'm sure there are characteristics of both groups, and that ratsnakes and racers have a common ancestor far enough back in time. I think all the tropical ratsnakes have some characteristics in common, especially some morphological ones. Whether they are convergent or shared derived, I don't know for sure, but my guess is they share some kind of common ancestry. Coelognathus, Gonyosoma, and Elaphe all share certain characteristics, and they seem to have ratsnake, as well as racer charactersistics. So, what will more in depth dna testing tell us?

My response:
You guess correctly that the racers share a common ancestor with the ratsnakes. This has been known for decades. Because of their close relationship, sometimes it is difficult to tell whether a snake is a racer or a ratsnake. The ratsnakes (all 33 species in Elaphe) form a natural group that is not polyphyletic. The racers are basal to this group. Senticolis appears to be outside of the ratsnake group also.

You wrote:
BTW, Utiger et al, did not remove prasina or frenata from the Elaphe, yet, for lack of sufficient data, but suggested they were closest to Gonyosoma, based on morphological characteristics. I agree. I think they should be placed in the Gonyosoma until we have further testing, and also think that the Vietnamese longnose ratsnake probably is closely allied with Gonyosoma, and should be tested again for possible removal from Rhynocophis.

MY response:
This is pure speculation on their part. I would not pay any attention to their suggestion. Morphology is not always reliable because of the greater likelihood of convergence.

You wrote:
I think there should be more in depth testing of Gonyosoma and others with the Elaphe and some racers. Lopez and Maxson used Coluber to compare to Gonyosoma, but needs to use several more genera to convince me.

My response:
In fact, Lopez and Maxson use a large number of racers to show that the ratsnakes (the 33 species of Old World and New World Elaphe) form a monophyletic group with the Lampropeltini. In contrast, Utiger et al. use but one species of racer, Ptyas.

You wrote:
Actually, Coluber has several characteristics shared with the Elaphe, especially E. taeniura, and I think they could have retained some morphological ones from a common ancestor. Yes, they may be convergent too, but it's worth testing. It seems to me that Gonyosoma species have more ratsnake characteristics than racer, but we'll see.

My response:
Gonyosoma is a racer. It is a foregone conclusion.

You wrote:
Helfenberger may have messed up some in his '01 paper, but I believe his ideas were mostly proposals for dividing the Elaphe into related groups. I think he could have held off on creating new genera, but Coelognathus seems to have been well received.

My response:
He may not have “messed up”. It is just that his 2001 paper is based on morphological characters. These sorts of characters are often conservative, and sometimes they are more prone to convergent evolution. They are thus less reliable when one is ascertaining branching order. That is why many scientists are turning to molecular data. Sometimes molecular data confirms conclusions drawn from morphological data; sometimes there is disagreement. There is definitely disagreement between his 2001 paper and Utiger et al.’s 2002 paper.

You wrote:
As a member of the Utiger et al. group '02, the stress has been put on dna testing to show relationships. This is better, but I feel there are still some problems, as already mentioned. Taking another example, let me say that climacophora could well have been derived from a taeniura/moellendorffi ancestor. I don't think this species should be in the "carinata" group. Carinata may well have been derived from the taeniura/moellendorffi group also, so could be allied with the Elaphe.

My response:
From their tree, it looks like E. carinata and E. climacophora are closely related. They both appear to share a recent common ancestor that may have been derived from a member in the taeniura-moellendorfii group. Since they are all closely related and since it is difficult, if not impossible, to distinguish these groups morphologically, they should be retained in the genus Elaphe.

You wrote:
Interesting stuff. I wouldn't mind having a couple more papers. I appreciate the one you already sent to me. Ever since I got into the ratsnakes in the late 80's I've wished I had the Dowling paper, and I'd also like to see/study the Keogh paper. Any chance you could send me a PDF file or link to these? I'd find them on my own if I knew where to look.

My response:
To find these papers, you would have to go to a University library. Or you can get them through your local library via interlibrary loan.

You wrote:
I agree that Senticolis is probably not most closely related to the New World ratsnakes (Lampropeltini), but I don't know how much of a racer it is. First, I like a taeniura/moellendorffi type ancestor for the Old World Elaphe, and that might work as an ancestor for Senticolis too.

My response:
Elaphe mandarina and E. conspicillata are the two species that are most basal to the ratsnakes according to Utiger et al. Tong et al. also have E. mandarina as most basal and E. rufodorsata more basal than E. taeniura, the common ancestor of the Old World ratsnakes would probably resemble E. rufodorsata, E. conspicillata and E. mandarina more than it would E. taeniura or E. moellendorffi.

You wrote:
The scutellation on Senticolis is quite different from the normal racer. Also, some other features, like the head shape, are quite ratsnake-like. Senticolis is a pretty strong constrictor too. Elaphe taeniura is a racer-like ratsnake, like Senticolis.

My response:
Senticolis may well have converged upon the ratsnakes morphologically.

You wrote:
The hemipenes morphology might not be very similar, but the Senticolis ancestor is likely a different and older species than taeniura, and related in other ways.

My response:
The ancestor of Senticolis may well be outside of the genus Elaphe altogether. Elaphe mandarina's hemipenial structure is quite similar to the other ratsnakes, showing that this characteristic evolved quite early. Senticolis' hemipenial structural is very different from those of the ratsnakes. This characteristic alone would seem to exclude Senticolis from the ratsnake clade.

You wrote:
Many of the most basal species have both ratsnake and racer type characters. I believe a basal type Asian ancestor of the ratsnakes was a very early invader of the New World (maybe late Oligocene/early Miocene) and gave rise to Senticolis or similar type ratsnake.

My response:
Does not look like it happened that way. It looks like the genus Elaphe evolved before a species of Old World Elaphe that is closely related to E. scalaris entered the US sometime in the Miocene to give rise to the New World species of Elaphe, such as E. flavirufa, E. obsoleta, E. vulpina and their close relatives, which include Lampropeltis, Arizona, Bogertophis, Stilosoma, Pituophis, Cemophora and Rhinocheilus. Senticolis arrived separately than this Elaphe ancestor. It is not part of the New World Elaphe-Lampropeltini clade. Senticolis is very likely a racer that is only convergently similar to the ratsnakes.

You wrote:
>>Elaphe mandarina and E. conspicillata are the two species that are most basal to the ratsnakes according to Utiger et al. Tong et al. also have E. mandarina as most basal and E. rufodorsata more basal than E. taeniura, the common ancestor of the Old World ratsnakes would probably resemble E. rufodorsata, E. conspicillata and E. mandarina more than it would E. taeniura or E. moellendorffi.

My response:
I don't think that being a basal member of a genus means that it has to be ancestral. Mandarina simply evolved from the early Elaphe ancestor, responding to the conditions that created it. It's more basal than taeniura, etc, because they hadn't been derived, yet, from the ancestral Elaphe. Same for rufodorsata which seems to be related to another early branching genus now residing in western Europe. These genera are highly derived and I doubt that they are much like the ancestral Elaphe which I would argue to be more like taeniura/moellendorffi, now at the core of the Old World Elaphe.

You wrote:
>>The ancestor of Senticolis may well be outside of the genus Elaphe altogether. Elaphe mandarina's hemipenial structure is quite similar to the other ratsnakes, showing that this characteristic evolved quite early. Senticolis' hemipenial structural is very different from those of the ratsnakes. This characteristic alone would seem to exclude Senticolis from the ratsnake clade.

My response:
Senticolis is adapted to subtropical conditions and is a quite old taxa. The ancestral Elaphe could have lived under much different conditions than modern Elaphe and could have had different hemipenal structure, like Senticolis. I agree it's possible that Senticolis could be more related to other colubrids, although it's very old, and not closely related to any existant species. Also, I think there's a lot of variation in hemipenal structure in Elaphe and not too much importance can be placed on that characteristic, w/o including other characteristics to make a stronger case.

You wrote:
>>Does not look like it happened that way. It looks like the genus Elaphe evolved before a species of Old World Elaphe that is closely related to E. scalaris entered the US sometime in the Miocene to give rise to the New World species of Elaphe, such as E. flavirufa, E. obsoleta, E. vulpina and their close relatives, which include Lampropeltis, Arizona, Bogertophis, Stilosoma, Pituophis, Cemophora and Rhinocheilus. Senticolis arrived separately than this Elaphe ancestor. It is not part of the New World Elaphe-Lampropeltini clade. Senticolis is very likely a racer that is only convergently similar to the ratsnakes.

My response:
In "A Biogeographical Analysis of the Chihuahuan Desert through its Herpetofauna", David J. Morafka (1977) argues that there was already an "Old Northern" Elaphe ancestor in N. A. when xeric conditions began to evolve in late Oligocene/Early Miocene. I think Senticolis may have evolved along with the mesquite/grassland/thornscrub vegetation that was evolving. Bogertophis may have evolved from the same or similar ancestor as a result to the evolving desert and other conditions. Bogertophis is kind of intermediate bt. the ancestral Elaphe and Pituophis, which probably evolved also on the Mexican Plateau as climate and vegetation evolved. Pantherophis could have been derived from this ancestral stock, or come from another invasion later on. I feel like it could have been a different Elaphe ancestor, similar to taeniura/moellendorffi, that evolved into the Pantherophis species, and not a scalaris-like ancestor, which is not too closely related to the other Old World Elaphe, or maybe even E. flavirufa itself was ancestral to Pantherophis. The invasion of the New World probably took place across the Bering Straits Land Bridge in more humid conditions than today. I do agree that the genus, Elaphe, probably evolved in the Old World to some degree before the New World invasion, but I think there was probably at least one New World invasion before the "Young Northern" stock evolved. Lampropeltis, Natrix, and Coluber were also present as Old Northern stock according to Morafka.

You wrote:
I don't think that being a basal member of a genus means that it has to be ancestral. Mandarina simply evolved from the early Elaphe ancestor, responding to the conditions that created it. It's more basal than taeniura, etc, because they hadn't been derived, yet, from the ancestral Elaphe. Same for rufodorsata which seems to be related to another early branching genus now residing in western Europe. These genera are highly derived and I doubt that they are much like the ancestral Elaphe which I would argue to be more like taeniura/moellendorffi, now at the core of the Old World Elaphe.

My response:
Most taxonomists classify rufodorsata, mandarina etc. in Elaphe. Some of the species of Elaphe are clearly more derived than others. The key question is whether these derived species are so disparate morphologically that they should be placed in several different genera. Since Utiger et al. do not give us any morphological reasons for transferring them to other genera, I would have to follow the lead of earlier systematists, such as Dowling, who left them in Elaphe. If anyone wants to convince me that these genera are valid, let them show me how to distinguish these genera from each other.

You wrote:
Senticolis is adapted to subtropical conditions and is a quite old taxa. The ancestral Elaphe could have lived under much different conditions than modern Elaphe and could have had different hemipenal structure, like Senticolis.

My response:
Since all species of Elaphe, whether Old World or new, have hemipenial structure that is unlike that of Senticolis, the last common ancestor of the 33 species of Elaphe probably had a different hemipenial structure than Senticolis. Senticolis would then be outside of the ratsnake clade. Since the next closest relatives of the ratsnakes are the racers, Senticolis is closer to the racers than to the ratsnakes according to hemipenial structure.

You wrote:
In "A Biogeographical Analysis of the Chihuahuan Desert through its Herpetofauna", David J. Morafka (1977) argues that there was already an "Old Northern" Elaphe ancestor in N. A. when xeric conditions began to evolve in late Oligocene/Early Miocene. I think Senticolis may have evolved along with the mesquite/grassland/thornscrub vegetation that was evolving. Bogertophis may have evolved from the same or similar ancestor as a result to the evolving desert and other conditions. Bogertophis is kind of intermediate bt. the ancestral Elaphe and Pituophis, which probably evolved also on the Mexican Plateau as climate and vegetation evolved. Pantherophis could have been derived from this ancestral stock, or come from another invasion later on.

My response:
Morafka's sepculation is interesting, but since then molecular data have become available. It paints the following picture:

An Old World species of Elaphe arrived in the New World from the Old World in the ealy Miocene. From this ancestor, all of the New World species of Elaphe evolved. Bogertophis, Arizona, Pituophis, Lampropeltis, Rhinocheilus, Cemophora, Stilosoma are all descendants of this Old World species of Elaphe. They all share a long intrapulmonary bronchus. Senticolis, unfortunately, does NOT appear to belong to this group.

You wrote:
I feel like it could have been a different Elaphe ancestor, similar to taeniura/moellendorffi, that evolved into the Pantherophis species,

My response:
This idea is unfortunately not supported by DNA data.

You wrote:
and not a scalaris-like ancestor, which is not too closely related to the other Old World Elaphe,

My response:
E. scalaris is the species that is closest to New World Elaphe, like it or not, according to DNA data.

You wrote:
or maybe even E. flavirufa itself was ancestral to Pantherophis.

My response:
That is one possibility I can support since E. flavirufa has a relatively long intrapulmonary bronchus. However, I disagree with the Pantherophis name since it cannot be distinguished from Old World Elaphe. You seem to have adopted this name. Can you tell me how Pantherophis differs from Elaphe?

You wrote:
The invasion of the New World probably took place across the Bering Straits Land Bridge in more humid conditions than today.

My response:
This is the route that some favors. However, this is not the only route between the Old and the New World. New World species of Nerodia are almost certainly descended from an Old World species of Natrix, which is a European genus. The distribution of Nerodia and Natrix suggests a Europe to eastern North America migration route. Elaphe could have come over the same way.

You wrote:
I do agree that the genus, Elaphe, probably evolved in the Old World to some degree before the New World invasion,

My response:
That is pretty much a foregone conclusion based on the DNA data, since Old World Elaphe branched off a few times before New World Elaphe appears on the tree.

You wrote:
but I think there was probably at least one New World invasion before the "Young Northern" stock evolved. Lampropeltis, Natrix, and Coluber were also present as Old Northern stock according to Morafka.

My response:
Morafka's speculation is interesting but it is still speculation. Molecular data on the New World colubrid snakes became available a few years after Morafka published his book. These data tell a clearer picture than Morafka can. They tell us that a species of Old World Elaphe most closely related to Elaphe scalaris begets New World Elaphe, and a New World Elaphe closest to Elaphe obsoleta begets Pituophis, Bogertophis, Arizona, E. guttata, E. vulpina, E. bairdi, and Lampropeltis. A species of Lampropeltis closest to L. pyromelana begets the other species of Lampropeltis as well as Cemophora, Rhinocheilus and Stilosoma. Senticolis appears to be an outsider to this N. American radiation of ratsnakes and their relatives.

Great thread, sounds like I got some bites. It will be interesting to see what this snake is considered to be more closely aligned with. I always thought of it as more of an elaphe due to the sum of its parts but closer inspection could prove otherwise. I have not been fortunate enough to film one yet in the wild. I would prefer to buy some cb's but they are astronomical in price, I could go on six road trips and have twice as much fun in the hunt for what a cb pair sells for. They are neat though.

Actually, Terry Cox is being too kind. I saw my first wild triaspis back in '01, and since then, have seen 4 more and purchased some cb's from a mutual friend. I'm a long way from being any type of green rat expert and everytime I know more about them, I find there is so much I don't know. To me, they're another part of the "cool Arizona herps" mystique. Similiar to the "West Texas herps" mystique. Frankly Terry, you should be the rat-king if anybody could claim that moniker.
Best...
Jim

Ha, ha, thanks, Jim. I agree about the Arizona mystique. One of the reasons retiring there is going to be so great is that you get to spend the rest of your life experiencing all the neat, new species, and habitat TC.

Don't keep rubbing in your retirement Terry! LOL! I still have 13 more years to go then I'll be joining you out there! Seriously, I can't think of too many other places I'd rather spend the rest of my days than out Arizona way.
Best..
Jim