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It is the closest relative to New World species of Elaphe and their relatives such as Bogertophis, Lampropeltis and Pituophis. It lives in western Europe, which makes it a candidate for the western Europe - eastern North America migration across the Thulean land bridge which connected the two continents during the Oligocene and Miocene. Its color pattern also resembles that of the New World ratsnakes. The striped morph could be a precursor to the striped morphs of Elaphe obsoleta. The blotched morph looks a lot like the pine and gopher snakes and I can also see the similarity between the H-shaped blotches in Bogertophis subocularis and some individuals of Elaphe scalaris. In terms of color pattern and DNA, Elaphe scalaris is a strong candidate as the species that is ancestral to the New World species of Elaphe and their close relatives in the Lampropeltini.
Ancestor of Bogertophis subocularis?

These guys do resemble subocs. color wise but behave and are built more like Pituophis with their hissing and all. To me they resemble lineaticollis which are very ratsnake like Pituophis. They are interesting and uncommonly kept. --Scott

Pituophis is almost certainly a descendant of the Elaphe obsoleta/bairdi/vulpina complex. If E. scalaris hisses like Pituophis, then Pituophis must have gotten this trait from their grandpa.

There was a recent thread on this forum regarding Foxsnakes and I posted a question regarding foxsnakes being a link between Elaphe and Pituophis. Terry Cox made a post stating "Pituophis is thought to have been derived from an early Elaphe ancestor in the Miocene". I have a pair of E. scalaris which a recent published paper separates scalaris from Elaphe to another genus Rhinoceris (sp). I'm not saying this is correct, but I am noting a recent paper. This separation possibly positions scalaris closer to racers. I've thought of and called my scalaris the European Pituophis noting their rostral scale and head similarities. This would fall in line with being a descendent of New World Elaphe, but having a few similarities with Pituophis. I think this is coming out the way I want to say it, LOL. I welcome more input on a very interesting thread subject.

Terry Parks

>>Pituophis is almost certainly a descendant of the Elaphe obsoleta/bairdi/vulpina complex. If E. scalaris hisses like Pituophis, then Pituophis must have gotten this trait from their grandpa.

Being lucky enough to have (finally) gotten a pair...I would definitly vote for the Pituophis connection....Frank

from Sacha Korell. I had wanted to add a pair to my collection for a couple years. They seem to be burrowers like Pituophis with the rostral scale they have. I used to go to Sacha Korell's website and see a pic of one of the parents of mine and the head looks just like a Pituophis. They may very well be linked to our North American Elaphe having a transition from pattern to stripes going from hatchling to adult. Good luck.

Terry Parks

>>Being lucky enough to have (finally) gotten a pair...I would definitly vote for the Pituophis connection....Frank

-----
Terry Parks

You wrote:
There was a recent thread on this forum regarding Foxsnakes and I posted a question regarding foxsnakes being a link between Elaphe and Pituophis. Terry Cox made a post stating "Pituophis is thought to have been derived from an early Elaphe ancestor in the Miocene".

My response:
The last time Elaphe and Pituophis shared a common ancestor, according to serum protein data of Dowling et al., is in the Pliocene, not the Miocene. After Pituophis budded off of the Elaphe lineage, Elaphe continues on relatively unchanged. Subsequent to the appearance of Pituophis, Elaphe guttata then budded off of this species. This ancestral species is almost certainly the Elaphe obsoleta/vulpina/bairdi complex. After E. guttata evolved, this complex then split into the present day E. obsoleta and E. vulpina. Not sure when E. bairdi last shared a common ancestor with E. obsoleta but there is no question they are closely related.

You wrote:
I have a pair of E. scalaris which a recent published paper separates scalaris from Elaphe to another genus Rhinoceris (sp). I'm not saying this is correct, but I am noting a recent paper. This separation possibly positions scalaris closer to racers.

My response:
Elaphe scalaris is no closer to the racers than is Elaphe porphyraceus. In fact, Elaphe situla, E. lineatus and Elaphe mandarina are all closer to the racers than is E. scalaris. The recent paper you mention (Utiger et al.) recognizes a large number of genera for the species of Elaphe. But since the authors give no diagnosis of these genera, there is no information on how they differ from each other. These authors apparently did what they did in order to adhere to Hennig’s principle of monophyly, which says that a taxon must consist of a common ancestor and all of its offsprings. To make a long story short, there are only 2 ways to make the ratsnakes conform to Hennig's principle. One is to group them all in a single genus, meaning that all species in Lampropeltis, Bogertophis, Pituophis, Cemophora, Stilosoma, Arizona and Rhinocheilus must now be moved back into Elaphe (analogous to what Arnold Kluge did when he lumped Charina, Lichanura and Calabaria into a single genus regardless of differences among them). The other alternative is to split Elaphe up into a dozen or so genera while maintaining Lampropeltis et al. as valid. Both of these alternatives are unacceptable since one requires excessive lumping and the other excessive splitting. But since Utiger et al. are trying to adhere to Hennig’s principle, they chose to split excessively. Splitting excessively results in taxa that are not distinguishable from one another, and that is what Utiger et al.’s proposal will result, if it is accepted. There is a sane 3rd alternative, and that would be to ignore Hennig’s principle and retain Elaphe as a paraphyletic genus, meaning that Elaphe will not include all descendants of a single common ancestor, but all species in Elaphe still has a nearest common ancestor. That means Elaphe obsoleta, E. mandarina, and E. scalaris will remain in Elaphe, while Pituophis, Lampropeltis etc. will stand. It is this 3rd and least destructive taxonomic alternative. It is this third and sane alternative that I prefer.

TP..you said:
>>There was a recent thread on this forum regarding Foxsnakes and I posted a question regarding foxsnakes being a link between Elaphe and Pituophis. Terry Cox made a post stating "Pituophis is thought to have been derived from an early Elaphe ancestor in the Miocene".

My response:
According to your scenario, E. vulpina would be the ancestor of Pituophis. I said Pituophis descended from an older Elaphe ancestor somewhere in Mexico. I believe E. vulpina and Pituophis are ecologically similar and have similar adaptations. They may have the same ancestor also.

You said:
I have a pair of E. scalaris which a recent published paper separates scalaris from Elaphe to another genus Rhinoceris (sp). I'm not saying this is correct, but I am noting a recent paper. This separation possibly positions scalaris closer to racers. I've thought of and called my scalaris the European Pituophis noting their rostral scale and head similarities. This would fall in line with being a descendent of New World Elaphe, but having a few similarities with Pituophis. I think this is coming out the way I want to say it, LOL. I welcome more input on a very interesting thread subject.
>>
>>Terry Parks

My response:
The paper split scalaris from the other Old World Elaphe because the DNA testing didn't show it closely related to Old World or New World Elaphe. But it is an Elaphe, although probably a little older. If anything, scalaris would have been ancestor to the Old World Elaphe, and that isn't likely. It is likely an early branch from the Old World Elaphe ancestor, adapting to the evolving xeric habitat in western Europe at that time. Scalaris is adapted to a temperate, dry climate, similar to Pituophis species. Pituophis is likely an ecological equivalent of scalaris, not an ancestor or descendant.

Terry Cox wrote:
The paper split scalaris from the other Old World Elaphe because the DNA testing didn't show it closely related to Old World or New World Elaphe. But it is an Elaphe, although probably a little
older. If anything, scalaris would have been ancestor to the Old World Elaphe, and that isn't likely. It is likely an early branch from the Old World Elaphe ancestor, adapting to the evolving xeric habitat in western Europe at that time. Scalaris is adapted to a temperate, dry climate, similar to Pituophis species. Pituophis is likely an ecological equivalent of scalaris, not an ancestor or descendant.

My response:
The paper split Elaphe scalaris from the other species of ratsnakes because it is the only way Utiger et al. can avoid recognizing paraphyletic taxa. E. scalaris is one of the closest relatives of New World Elaphe. It is most likely the ancestor of New World Elaphe. Even if it is not a direct ancestor, it is the equivalent of an aunt or uncle, i.e. a sibling species of the ancestor of New World Elaphe. The mtDNA data does NOT show this species to be an early branch at all. Elaphe mandarina, E. taeniura, E. persicus, E. rufodorsata and E. longissima, to name but a few, all branched off earlier than E. scalaris. E. scalaris is one of the more derived species within Elaphe. It is basal to North American Elaphe and it is in a perfect geographic location to make the crossing from western Europe to eastern N. America, where Pituophis first evolved, also according to mtDNA data in a separate paper. In that paper, the pine snakes are the most basal lineage whereas the gopher snakes are derived.

RS said:
"The mtDNA data does NOT show this species to be an early branch at all. Elaphe mandarina, E. taeniura, E. persicus, E. rufodorsata and E. longissima, to name but a few, all branched off earlier than E. scalaris. E. scalaris is one of the more derived species within Elaphe."

My response:
I agree. What I meant to say was that it was an early branch of the Elaphe (quatuorlineata, schrencki, dione, carinata, etc.) that was left by Utiger et al. I know where it's at on the tree. I was clumsy writing that part.

E. mandarina split from the tree long before scalaris, but is unlikely to be an ancestor to any ratsnakes outside of the new genus Euprepiophis. Scalaris and mandarina are both very derived, so I don't know how scalaris could be an ancestor to the Lampropeltini, but it is close to them. There are other species in East Asia, namely taeniura and moellendorffi. I think moellendorffi is the older species, and is more adapted to a warm temperate, deciduous ecosystem, similar to the one the ancestral Elaphe would have had to survive in in the early Miocene, some 20 mya, or so. This habitat and climate is restricted to s.e. China at present.

I know E. obsoleta is adapted to a temperate deciduous ecosystem also, but not as warm as moellendorffi's, and I don't think it is old enough to have been around in the early Miocene. If it is younger than scalaris, obsoleta must have been derived around the end of the Miocene or in the Pliocene. My 2 cents anyway

What source material are you guys getting this info from......This is the most interesting exchange I've read here on the forums(of course I'm predjudiced because I have a pair of scalaris).
Frank

We are getting the molecular, taxonomic information from the recent, 2002, Utiger et al. paper, and the MP tree in that paper, which shows the branching order of the evolving Elaphe genus. We are also using other papers and books we've read as source material for our arguments of whether there should be new genera, or not; which species gave rise to which, if any; and our private theories of how the Elaphe probably came to be, which is very speculative. Many of these sources have been cited or linked in previous posts.

Glad it is good entertainment, and hopefully educational for some of us. I'm very jealous of you guys that have the species scalaris, which I've never worked with. I'd like to see more pictures of those guys, especially close-ups and head shots. Later...TC.

Terry wrote:
E. mandarina split from the tree long before scalaris, but is unlikely to be an ancestor to any ratsnakes outside of the new genus Euprepiophis.

My response:
Yes, E. mandarina branched off real early. But does this mean that it is deserving of a new genus? I don't think so. Its hemipenial structure, for example, which is traditionally one of the key characters in defining snake genera, differs very little from those of other species of Elaphe, including Elaphe obsoleta. Pituophis, OTOH, has hemipenial structures that are clearly more derived and different than that of E. mandarina. It appears that although it had branched off quite early, it has changed little (scientists call this sort of phenomenon stasis). E. conspicillata also branched off early from other species of Elaphe. The similarities between these two species and other species of Elaphe would most likely be the primitive features within this genus. Until Utiger et al. or someone else show how E. mandarina differ from other species of Elaphe, there is no justification for transferring these two species of Elaphe to another genus.

Terry wrote:
Scalaris and mandarina are both very derived, so I don't know how scalaris could be an ancestor to the Lampropeltini,

My response:
E. obsoleta is even more derived than E. scalaris, so this is not a problem at all. If E. obsoleta can be ancestral to the Lampropeltini, there is no reason why E. scalaris cannot be ancestral to E. obsoleta.

Terry wrote:
but it is close to them. There are other species in East Asia, namely taeniura and moellendorffi. I think moellendorffi is the older species, and is more adapted to a warm temperate, deciduous ecosystem, similar to the one the ancestral Elaphe would have had to survive in in the early Miocene, some 20 mya, or so. This habitat and climate is restricted to s.e. China at present.

My response:
These species are closer to the base of the tree than E. scalaris, which is more likely to be the immediate ancestor of New World Elaphe than the Asiatic species, especially considering the fact that no Elaphe can be found in the Pacific coast states. If Elaphe entered the New World via the Beringia land bridge, there should be some evidence of their past presence on the West Coast. There is none that I know of.

Terry wrote:
I know E. obsoleta is adapted to a temperate deciduous ecosystem also, but not as warm as moellendorffi's, and I don't think it is old enough to have been around in the early Miocene. If it is
younger than scalaris, obsoleta must have been derived around the end of the Miocene or in the Pliocene.

My response:
What makes you think E. obsoleta could not have been around in the Miocene?

RS wrote:
These species are closer to the base of the tree than E. scalaris, which is more likely to be the immediate ancestor of New World Elaphe than the Asiatic species, especially considering the fact that no Elaphe can be found in the Pacific coast states. If Elaphe entered the New World via the Beringia land bridge, there should be some evidence of their past presence on the West Coast. There is none that I know of.

My response:
Whether the ancestral Elaphe entered the New World via Beringia or from w. Europe, the fact remains that the ancestral Elaphe had to be adapted to a warm, humid, temperate, Arcto-Tertiary geoflora that was holarctic. Differentiation into more xeric ecosystems didn't occur until sometime near the Miocene. That is why I like an Asiatic ancestor even though habitat doesn't allow an Elaphe in the western coastal regions today.

RS wrote:
What makes you think E. obsoleta could not have been around in the Miocene?

My response:
It could have been around in the Miocene if the proper habitat was there for it to evolve in. I don't think Elaphe obsoleta could have been the ancient ancestor that migrated into the New World through Arcto-Tertiary vegetation. The Elaphe ancestor may have given rise to obsoleta, but obsoleta is a Young Northern species, and I don't think it would have occupied the same environment as the Elaphe ancestor. It could be descended from an Old Northern Elaphe ancestor, along with other Young Northern species.

In discussing the general paleoecology of the northern Mexican Plateau, Morafka (1977, A Biogeographical Analysis of the Chihuahuan Desert through its Herpetofauna), writes this piece....pgs. 172-73.

"The first occurrence of North American colubrid snakes in the Miocene indicates a coupling of previous evolutionary events with the paleogeographical accessibility of the continent. The invasion of apparently modern genera suggests previous Old World evolution. Considering the time and route of entrance, virtually all of these early arrivals must have been Old Northern stocks moving through Arcto-Tertiary vegetation (Savage & Scott, personal communication). They could have come via Beringia or Europe {*as part of the Madro-Tethyan biota described by Axelod [1975. Ann. Missouri Bot. Garden 62 (2): 280-334]}. The presence of Elaphe and Lampropeltis in Miocene is already documented. The general pattern of dispersal from Old World centers is illustrated by the colubrids Coluber, Elaphe, Natrix, and the crotaline Agkistrodon. These stocks may have made a northern entrance onto the newly erected Mexican Plateau (and other portions of the Cordilleran region) by way of the Arcto-Tertiary (especially riparian) corridors fingering southward in early Neogene. As a Madro-Tertiary vegetation took form and expanded on the Plateau, these stocks gave rise, in situ, to the Young Northern (Mexican Plateau centered and Madro-Tertiary vegetation associated genera. Explicitly, Elaphe gave rise to Pituophis, Natrix to Thamnophis, and Agkistrodon to Crotalus and Sistrurus. Paleoecological conditions throughout the plains and southern Cordilleran North America could have been suitable sites for these developments."

Because the Madro-Tertiary Geoflora arose bt. the old, Arcto-Tertiary, and Neotropical Geofloras in the vicinity of the Mexican Highlands, I came to the conclusion that most of the Young Northern colubrid species evolved there, probably in the later Miocene.

After writing about his beliefs that Pituophis melanoleucus and P. deppei are actually the same species, Morafka concluded with this paragraph (pg. 76-77)...

"Duellman (1960) concludes that Pituophis lineaticollis is a species distinct from P. deppei, and sympatric with that form. His analysis, based on trunk and subcaudal scale counts, would make lineaticollis the only other valid species of the genus. It is intriguing that this last form resembles strikingly Eaphe subocularis in having a single pair of prefrontals, and extremely distinctive dorsal patterns consisting of neck longitudinal stripes (black) and posterior trunk blotches (brown/black) on a yellowish ground color. E. subocularis furthermore has Pituophis-like hemipenis (Dowling, 1957), P. lineaticollis is completely allopatric to E. subocularis, the former being a montane species of southern Sierra Madres south into the highlands of Guatemala, while the latter is restricted to the Chihuahuan Desert north of the 25th parallel. In the 500 kilometer interval between the two forms, plateau populations of Pituophis appears to undergo a series of character displacements as they proceed northward approaching populations of E. subocularis. In the northward shift from P. lineaticollis to deppei the subocularis-like pattern gives way to a completely blotched dorsal pattern (excepting the head which often remains unicolor). Further north, as the deppei morphs integrade with melanoleucus, the head becomes blotched and barred with increasing frequency, the Elaphe-like paired prefrontals become four, and two labials in the orbit are replaced by one. It is this highly modified melanoleucus which is in actual sympatric contact with E. subocularis. The biogeographical significance of this apparent character displacement will be discussed later."

From this paragraph it seems to me that E. subocularis and Pituophis lineaticollis are fairly closely related, and that P. lineaticollis evolved from the ancestral Elaphe. It also seems that P. lineaticollis is the older species in Pituophis and that P. melanoleucus evolved in the northern Mexican Highlands.

Terry wrote:
Whether the ancestral Elaphe entered the New World via Beringia or from w. Europe, the fact remains that the ancestral Elaphe had to be adapted to a warm, humid, temperate, Arcto-Tertiary geoflora that was holarctic. Differentiation into more xeric ecosystems didn't occur until sometime near the Miocene. That is why I like an Asiatic ancestor even though habitat doesn't allow an Elaphe in the western coastal regions today.

My response:
E. obsoleta is such a species.

I wrote:
What makes you think E. obsoleta could not have been around in the Miocene?

Terry wrote:
It could have been around in the Miocene if the proper habitat was there for it to evolve in. I don't think Elaphe obsoleta could have been the ancient ancestor that migrated into the New World through Arcto-Tertiary vegetation. The Elaphe ancestor may have given rise to obsoleta, but obsoleta is a Young Northern species,

My response:
E. obsoleta is not young at all. Holman (2000, Fossil Snakes of North America, Indiana University Press, p. 163) says that it has been found in the late Miocene of Nebraska. E. kansensis, which is most similar to either E. obsoleta or E. vulpina depending on the author, is known from the middle Miocene from Saskatchewan and Texas, among other localities. Saskatchewan is not too far from the Thulean land bridge. The Beringia land bridge is much farther away.

Terry wrote:
and I don't think it would have occupied the same environment as the Elaphe ancestor. It could be descended from an Old Northern Elaphe ancestor, along with other Young Northern species.

My response:
This “old northern Elaphe ancestor” is apparently E. kansensis, and it doesn’t look like it came through the Beringia land bridge. E. kansensis is unknown in the western states.

Terry wrote:
After writing about his beliefs that Pituophis melanoleucus and P. deppei are actually the same species, Morafka concluded with this paragraph (pg. 76-77)...

"Duellman (1960) concludes that Pituophis lineaticollis is a species distinct from P. deppei, and sympatric with that form. His analysis, based on trunk and subcaudal scale counts, would make lineaticollis the only other valid species of the genus. It is intriguing that this last form resembles strikingly Eaphe subocularis in having a single pair of prefrontals, and extremely distinctive dorsal patterns consisting of neck longitudinal stripes (black) and posterior trunk blotches (brown/black) on a yellowish ground color. E. subocularis furthermore has Pituophis-like hemipenis (Dowling, 1957), P. lineaticollis is completely allopatric to E. subocularis, the former being a montane species of southern Sierra Madres south into the highlands of Guatemala, while the latter is restricted to the
Chihuahuan Desert north of the 25th parallel. In the 500 kilometer interval between the two forms, plateau populations of Pituophis appears to undergo a series of character displacements as they proceed northward approaching populations of E. subocularis. In the northward shift from P. lineaticollis to deppei the subocularis-like pattern gives way to a completely blotched dorsal pattern (excepting the head which often remains unicolor). Further north, as the deppei morphs integrade with melanoleucus, the head becomes blotched and barred with increasing frequency, the Elaphe-like paired prefrontals become four, and two labials in the orbit are replaced by one. It is this highly modified melanoleucus which is in actual sympatric contact with E. subocularis. The biogeographical significance of this apparent character displacement will be discussed later."

From this paragraph it seems to me that E. subocularis and Pituophis lineaticollis are fairly closely related, and that P. lineaticollis evolved from the ancestral Elaphe. It also seems that P. lineaticollis is the older species in Pituophis and that P. melanoleucus evolved in the northern Mexican Highlands.

My response:
Dowling and Price (1988, 20:52-63) point out that P. melanoleucus, P. lineaticollis, and P. deppei have identical microdermatoglyphic patterns. They generally find that species that are closely related have similar microdermatoglyphic patterns. This is apparently the case for the several nominal species of Pituophis. This character supports Morafka’s conclusion that P. deppei and P. melanoleucus are conspecific. The microdermatoglyphic patterns of Pituophis and Elaphe vulpina are similar; both have “canaliculi”. Bogertophis subocularis has a pattern similar to Pituophis, but it lacks canaliculi completely. It is nevertheless possible that Bogertophis is a derived Pituophis, but Dowling and Price point out that B. rosaliae and B. subocularis lack the “epiglottal process,” which is possessed by all members of Pituophis but no Elaphe has this character. Therefore Bogertophis and Elaphe are more closely related to each other than either is to Pituophis according to this character. It is true that the hemipenis of Pituophis and Bogertophis are similar, suggesting a close relationship. Indeed, some subspecies of Pituophis melanoleucus do have lorilabial scales, like those in Bogertophis, but neither deppei nor lineaticollis has them. So far it would seem that Bogertophis could have been derived from either Elaphe or Pituophis, since there is evidence to support both hypothesis, and Morafka seems to favor the latter. The tiebreaker, however, is immunological distance. Dowling and Price point out that Pituophis, Arizona, E. vulpina and E. guttata all differ from each other by 10 or fewer immunological distance units (AID), meaning that they all share a fairly recent common ancestor. Bogertophis, on the other hand, differs by over 20 AID from E. obsoleta. That means Bogertophis diverged from Elaphe before Pituophis or Arizona even evolved. The similarities between Pituophis and Bogertophis, though striking, are therefore most likely convergences and/or the reappearance of an ancestral character, i.e. an atavism. Therefore Morafka’s hypothesis of a close relationship between Pituophis and Bogertophis is refuted by molecular data. It is demonstration why DNA data is favored by most systematists for resolving branching order.

As for his hypothesis that Pituophis evolved on the Mexican plateau, this is not supported by mtDNA data, which is very good at telling us where a species may have originated and where it has since dispersed. MtDNA data shows that the pine snakes (P. m. melanoleucus/lodingi/mugitus) evolved first and the other subspecies (the bullsnakes and gopher snakes) then evolved from the pine snakes. MtDNA can tell us that because the number of mtDNA lineages in a younger population are only a subset of the total number of mtDNA lineages in an older population, since only a few individuals are needed to establish a new population as a species’ range expands. It is also extremely unlikely that all mtDNA lineages in the older population will have at least one representative in a new population.

Nice try Terry, but Bogertophis is only convergently similar to Pituophis according to serum protein data, and a fossil species of Elaphe that is very closely related to E. obsoleta and E. vulpina has been documented in the mid-Miocene of Saskatchewan, Canada. E. obsoleta and E. vulpina have both been recorded from the late Miocene of Nebraska. There is no doubt that E. obsoleta/vulpina is a direct descendant of the species of Elaphe which had migrated to the New World, probably via the Thulean land bridge connceting eastern North America and Europe. The oldest fossil record for Elaphe in western N. America is Elaphe vulpina, from the Pliocene in eastern Washington state, not old enough to be ancestor of either New World Elaphe or Lampropeltis.

RS wrote:
>>E. obsoleta is not young at all. Holman (2000, Fossil Snakes of North America, Indiana University Press, p. 163) says that it has been found in the late Miocene of Nebraska. E. kansensis, which is most similar to either E. obsoleta or E. vulpina depending on the author, is known from the middle Miocene from Saskatchewan and Texas, among other localities. Saskatchewan is not too far from the Thulean land bridge. The Beringia land bridge is much farther away.

My response:
E. obsoleta is young compared to the ancestral Elaphe. It is an existant species. Holman believed that E. kansensis was ancestral to E. vulpina. Saskatchewan is just east of the Rocky Mtns., and north of Montana. I would say that was west. Also, another species of Elaphe, pliocenica, is from an Idaho fossil site. Holman states, "It is possible that Elaphe pliocenica is the last in the line of an archaic northwestern Elaphe clade or even that it represents the last gasp of an unrecognized archaic colubrid genus (p.165)." Unraveling the past of the Elaphe genus in the New World is very tricky. Who knows how much fossil data we don't have?

RS wrote:
>>Nice try Terry, but Bogertophis is only convergently similar to Pituophis according to serum protein data, and a fossil species of Elaphe that is very closely related to E. obsoleta and E. vulpina has been documented in the mid-Miocene of Saskatchewan, Canada. E. obsoleta and E. vulpina have both been recorded from the late Miocene of Nebraska. There is no doubt that E. obsoleta/vulpina is a direct descendant of the species of Elaphe which had migrated to the New World, probably via the Thulean land bridge connceting eastern North America and Europe. The oldest fossil record for Elaphe in western N. America is Elaphe vulpina, from the Pliocene in eastern Washington state, not old enough to be ancestor of either New World Elaphe or Lampropeltis.

My response:
There was another species of fossil Elaphe that Holman thinks is closest to E. obsoleta, called, Elaphe buisi. He said the fossils are very close to obsoleta and Bogertophis subocularis. I would like to know some data from fossils in Mexico, but Holman doesn't mention any of these. Elaphe flavirufa had to evolve from one of the ancestors, or were there more? Where did Senticolis triaspis come from? I think there are still lots of questions to answer, and a lot we don't know. We can't say E. kansensis is the Eurasian immigrant that produced the Lampropeltini. There must have been more species and more fossils to find. I wonder what the Eurasian fossil record is like for Elaphe and how extant species would match up?

Terry wrote:
E. obsoleta is young compared to the ancestral Elaphe. It is an existant species. Holman believed that E. kansensis was ancestral to E. vulpina.

My response:
Late Miocene is not exactly “young” for a species. E. obsoleta and E. vulpina, according to molecular data, are close relatives. As I said, other authors claim that E. kansensis is closer to E. obsoleta. E. obsoleta may have only split from E. vulpina quite recently, I would have to review the available molecular data to be sure. But whether E. kansensis is closer to E. obsoleta or E. vulpina, it is almost certainly ancestral to both. E. kansensis is identified on the basis of vertebral differences between it and extant species of Elaphe. Scientists know that vertebral characters are not always species-specific. Some species, such as Lampropeltis alterna, are identical in vertebral structure to closely related species, such as L. mexicana. Other species (e.g. L. getulus) may differ intraspecifically in this character. E. kansensis may well be conspecific with either E. vulpina or E. obsoleta despite differences in their vertebra.

Terry wrote:
Saskatchewan is just east of the Rocky Mtns., and north of Montana. I would say that was west.

My response:
It is certainly west of the Mississippi River, but still a long distance from the Bering Strait and also separated from it by the Rocky Mountains. Besides, there is no fossil Elaphe of any kind from the west coast, as one would expect from a Beringia migration route. The oldest one is E. vulpina, and it barely reaches eastern Washington in the Pliocene, entirely too “young” to be the ancestral species of New World Elaphe. Saskatchewan can be easily reached from Ellesmere Island when the climate was warm, as it was during the late Oligocene to early Miocene.

Terry wrote:
Also, another species of Elaphe, pliocenica, is from an Idaho fossil site. Holman states, "It is possible that Elaphe pliocenica is the last in the line of an archaic northwestern Elaphe clade or even that it represents the last gasp of an unrecognized archaic colubrid genus (p.165)."

My response:
This species (mid-Pliocene in age) is entirely too young to have anything to do with how Old World Elaphe entered the New World.

Terry wrote:
Unraveling the past of the Elaphe genus in the New World is very tricky. Who knows how much fossil data we don't have?

My response:
Scientific conclusions must be based on the available scientific evidence. It cannot be based on “fossil data we don’t have.” Holman may speculate about an archaic northwestern Elaphe clade, but there is no fossil evidence of such. The Thulean land bridge is not as well known as the Beringia land bridge, even among scientists. Therefore we find more speculation and presumption about a Beringia crossing for nearctic-palearctic faunal exchanges in the literature than the more probable Thulean crossing for Elaphe.

RS wrote:
>>Nice try Terry, but Bogertophis is only convergently similar to Pituophis according to serum protein data, and a fossil species of Elaphe that is very closely related to E. obsoleta and E. vulpina has been documented in the mid-Miocene of Saskatchewan, Canada. E. obsoleta and E. vulpina have both been recorded from the late Miocene of Nebraska. There is no doubt that E. obsoleta/vulpina is a direct descendant of the species of Elaphe which had migrated to the New World, probably via the Thulean land bridge connceting eastern North America and Europe. The oldest fossil record for Elaphe in western N. America is Elaphe vulpina, from the Pliocene in eastern Washington state, not old enough to be ancestor of either New World Elaphe or Lampropeltis.

Terry wrote:
There was another species of fossil Elaphe that Holman thinks is closest to E. obsoleta, called, Elaphe buisi. He said the fossils are very close to obsoleta and Bogertophis subocularis.

My response:
That would not be surprising. If Elaphe obsoleta is the species that made the crossing into the New World or a direct descendant of it, then it should be similar to Bogertophis. That is because molecular data shows that Bogertophis became reproductively isolated from Elaphe shortly after the ancestral species of Elaphe entered the New World. The precursor of Bogertophis may not have evolved into the present form until much later. E. buisi may be the suitable ancestor of Bogertophis and the descendant of E. obsoleta. It is located in Oklanhoma, making it geographically close to Bogertophis. Holman’s observation does not contradict the close relationship between Elaphe obsoleta and Bogertophis. It does contradict Morafka’s hypothesis of a close relationship between Pituophis lineaticollis and Bogertophis.

Terry wrote:
I would like to know some data from fossils in Mexico, but Holman doesn't mention any of these.

My response:
Fossil data from foreign countries, even close neighbors like Mexico, are much harder to come by. Most fossil specimens are probably obtained by local museums from nearby localities. Out of state and out of the country expeditions are much less frequent.

Terry wrote:
Elaphe flavirufa had to evolve from one of the ancestors, or were there more? Where did Senticolis triaspis come from? I think there are still lots of questions to answer, and a lot we don't know.

My response:
Quite correct. There is a lot we do not know. That may be why some people are still insisting that Senticolis is part of the Lampropeltini. Personally, I believe that Senticolis may be a racer that may have entered the US perhaps from Beringia, not a descendant of E. obsoleta or E. kansensis or E. scalaris. This is corroborated by protein data, as Dowling and Fries (1988 Herpetologica 43:206) write: "Lawson and Dessauer (1981) found S. triaspis to be far distant biochemically from Arizona, Lampropeltis, and Pituophis, as well as from the New World and Old World species of Elaphe that they examined (E. carinata, E. guttata, E. moellendorffi, E. obsoleta, E. radiata, E. rufodorsata, E. scalaris, E. schrenckii, E. subocularis, E. vulpina)" There can be little doubt that Senticolis is a racer, not a ratsnake.

Terry wrote:
We can't say E. kansensis is the Eurasian immigrant that produced the Lampropeltini.

My response:
We cannot. E. obsoleta, however, is unquestionably closely related to the Lampropeltini and it (or the closely related E. vulpina) is apparently ancestral to Pituophis, Arizona and Bogertophis, which are 3 of the genera in the Lampropeltini. Since E. kansensis is a mid-Miocene species closely related to E. obsoleta and/or E. vulpina, and it was found in Saskatchewan, it is more likely to be linked to the species that migrated to the New World from the Old World than, say, the Pliocene fossil E. pliocenica. E. kansensis therefore is a close relative of the ancestor of New World Elaphe and the Lampropeltine genera, if not the direct ancestor.

Terry wrote:
There must have been more species and more fossils to find. I wonder what the Eurasian fossil record is like for Elaphe and how extant species would match up?

My response:
Relationships between fossil species and extant species are harder to figure out because DNA data is not available in general from fossils. Relationships among extant species are easier. Molecular, morphological, and biogeographical data suggest that Old World Elaphe is ancestral to New World Elaphe, and that New World Elaphe is ancestral to the Lampropeltini. MtDNA data shows that E. scalaris is the species of Elaphe closest to New World Elaphe. Immunological data show that Elaphe quatuorlineata, Elaphe scalaris and Elaphe quadrivirgata are all similarly close to E. obsoleta. Immunological data, however, is less precise than mtDNA data. Therefore I believe that E. scalaris is probably the closest relative, and also probably the direct ancestor of New World Elaphe and the Lampropeltini, because of its present distribution (making it a good candidate to make the Thulean land bridge crossing) and its morphology (its color patterns closely resemble that of E. obsoleta and Bogertophis subocularis).

RS wrote:
Late Miocene is not exactly “young” for a species. E. obsoleta and E. vulpina, according to molecular data, are close relatives. As I said, other authors claim that E. kansensis is closer to E. obsoleta. E. obsoleta may have only split from E. vulpina quite recently, I would have to review the available molecular data to be sure. But whether E. kansensis is closer to E. obsoleta or E. vulpina, it is almost certainly ancestral to both. E. kansensis is identified on the basis of vertebral differences between it and extant species of Elaphe. Scientists know that vertebral characters are not always species-specific. Some species, such as Lampropeltis alterna, are identical in vertebral structure to closely related species, such as L. mexicana. Other species (e.g. L. getulus) may differ intraspecifically in this character. E. kansensis may well be conspecific with either E. vulpina or E. obsoleta despite differences in their vertebra.

My response:
E. kansensis dates from mid Miocene, which is around 14-15 ma, at least, and dies out around the time that E. vulpina and E. obsoleta are getting started, around 5-6 ma, according to what I've read. This species could definately have been the ancestor of vulpina or obsoleta, but so could have E. buisi, or E. pliocenica. I believe it was, "Out with the old, and in with the new."

RS wrote:
It is certainly west of the Mississippi River, but still a long distance from the Bering Strait and also separated from it by the Rocky Mountains. Besides, there is no fossil Elaphe of any kind from the west coast, as one would expect from a Beringia migration route. The oldest one is E. vulpina, and it barely reaches eastern Washington in the Pliocene, entirely too “young” to be the ancestral species of New World Elaphe. Saskatchewan can be easily reached from Ellesmere Island when the climate was warm, as it was during the late Oligocene to early Miocene.

My response:
You probably know about the orogenies of N.A. mtn. ranges. The continent was pretty flat when the colubrid ancestors invaded. The Rocky Mtn. orogeny was partly what caused the great climate changes throughout the Miocene, which led to the great radiation of the Lampropeltini. There's very few early Miocene colubrid fossils and it's very possible that Elaphe was already present as early as 24 ma at the start of the Miocene. The invading species probably weren't E. kansensis or E. buisi.

RS wrote (about E. pliocenica):
This species (mid-Pliocene in age) is entirely too young to have anything to do with how Old World Elaphe entered the New World.

My response:
The fossil is from mid-Pliocene. That doesn't mean that the species only existed then. It probably died out at that time, and there weren't any other fossils of this old species.

RS wrote:
Scientific conclusions must be based on the available scientific evidence. It cannot be based on “fossil data we don’t have.” Holman may speculate about an archaic northwestern Elaphe clade, but there is no fossil evidence of such. The Thulean land bridge is not as well known as the Beringia land bridge, even among scientists. Therefore we find more speculation and presumption about a Beringia crossing for nearctic-palearctic faunal exchanges in the literature than the more probable Thulean crossing for Elaphe.

My response:
Sure, scientists base conclusions on evidence, but if they didn't ever speculate, how would they ever develop theories. Ya know, I'll give you credit for coming up with the Thulean land bridge. I'm not going to say there isn't a chance that Elaphe ancestors came that way. I'm still thinking about it as a matter of fact. But I'm sure not going to put all my eggs in one basket and rule out all other possibilities. I think there's a good chance there was an Asian species crossing the Bering land bridge. I would even vote for an Elaphe schrencki or E. dione, if they weren't such young species.

RS wrote:
That would not be surprising. If Elaphe obsoleta is the species that made the crossing into the New World or a direct descendant of it, then it should be similar to Bogertophis. That is because molecular data shows that Bogertophis became reproductively isolated from Elaphe shortly after the ancestral species of Elaphe entered the New World. The precursor of Bogertophis may not have evolved into the present form until much later. E. buisi may be the suitable ancestor of Bogertophis and the descendant of E. obsoleta. It is located in Oklanhoma, making it geographically close to Bogertophis. Holman’s observation does not contradict the close relationship between Elaphe obsoleta and Bogertophis. It does contradict Morafka’s hypothesis of a close relationship between Pituophis lineaticollis and Bogertophis.

My response:
I don't know why you insist that E. obsoleta could be the Elaphe ancestor from Eurasia. This is a late Miocene species that is still alive today and well adapted to the modern world. And E. buisi was an older species. I doubt seriously obsoleta could have evolved into that species.

RS wrote:
Quite correct. There is a lot we do not know. That may be why some people are still insisting that Senticolis is part of the Lampropeltini. Personally, I believe that Senticolis may be a racer that may have entered the US perhaps from Beringia, not a descendant of E. obsoleta or E. kansensis or E. scalaris. This is corroborated by protein data, as Dowling and Fries (1988 Herpetologica 43:206) write: "Lawson and Dessauer (1981) found S. triaspis to be far distant biochemically from Arizona, Lampropeltis, and Pituophis, as well as from the New World and Old World species of Elaphe that they examined (E. carinata, E. guttata, E. moellendorffi, E. obsoleta, E. radiata, E. rufodorsata, E. scalaris, E. schrenckii, E. subocularis, E. vulpina)" There can be little doubt that Senticolis is a racer, not a ratsnake.

My response:
Are we to believe Utiger et al. are like god on all the other species they tested and not even close with Senticolis? I understand why you don't like the placement of Senticolis, but according to the molecular data of Utiger et al., Senticolis is closer to the Lampropeltini than E. scalaris is. If I'm going to use their data as evidence of branching order, I have to consider where they put Senticolis. And if Senticolis is a racer, why doesn't it branch closer to the racers, or even Ptyas, then to the Lampropeltini? Obviously, this is not the last word on Senticolis, and as we've said before, more testing needs to be done. Of course, I have another reason for responding to your Senticolis statements. I don't think we know enough about how the Southwestern U.S. and Mexican species have evolved. That will take some more research.

RS wrote:
Relationships between fossil species and extant species are harder to figure out because DNA data is not available in general from fossils. Relationships among extant species are easier. Molecular, morphological, and biogeographical data suggest that Old World Elaphe is ancestral to New World Elaphe, and that New World Elaphe is ancestral to the Lampropeltini. MtDNA data shows that E. scalaris is the species of Elaphe closest to New World Elaphe. Immunological data show that Elaphe quatuorlineata, Elaphe scalaris and Elaphe quadrivirgata are all similarly close to E. obsoleta. Immunological data, however, is less precise than mtDNA data. Therefore I believe that E. scalaris is probably the closest relative, and also probably the direct ancestor of New World Elaphe and the Lampropeltini, because of its present distribution (making it a good candidate to make the Thulean land bridge crossing) and its morphology (its color patterns closely resemble that of E. obsoleta and Bogertophis subocularis).

My response:
As long as we're speculating here, how come you didn't include E. schrencki, or for that matter E. dione, as possible ancestors for the Lampropeltini? Actually these species seem to resemble New World Elaphe very closely, and I remember my first look at schrencki and thinking it looked just like Lampropeltis g. getula.

I don't think E. scalaris could be the Elaphe ancestor of the Lampropeltini. Since the Thulean land bridge broke up by the early Miocene, the ancestor would have had to have been on Iceland by then, and scalaris is way too young for that. The Elaphe ancestor could have entered the New World from Iceland in the Miocene, but would have been an archaic Elaphe, not scalaris, or a scalaris ancestor. Another possibility is that the archaic Elaphe ancestor was E. kansensis, E. buisi, or E. pliocenica, which may have been a Eurasian species also. I don't know anything about the Eurasian fossils, yet, but it sounds like a future project

Terry wrote:
E. kansensis dates from mid Miocene, which is around 14-15 ma, at least, and dies out around the time that E. vulpina and E. obsoleta are getting started, around 5-6 ma, according to what I've read. This species could definately have been the ancestor of vulpina or obsoleta, but so could have E. buisi, or E. pliocenica. I believe it was, "Out with the old, and in with the new."

My response:
It would be an anachronism for either E. buisi or E. pliocenica to be ancestral to E. vulpina and E. obsoleta. It would be analogous to E. obsoleta being ancestral to E. kansensis. Besides, E. kansensis may well be conspecific with either E. vulpina or E. obsoleta since they are distinguished by differences in their vertebra, and since this character varies as much within L. getulus as it does between different genera of some snakes.

Terry wrote: You probably know about the orogenies of N.A. mtn. ranges. The continent was pretty flat when the colubrid ancestors invaded. The Rocky Mtn. orogeny was partly what caused the great climate changes throughout the Miocene, which led to the great radiation of the Lampropeltini. There's very few early Miocene colubrid fossils and it's very possible that Elaphe was already present as early as 24 ma at the start of the Miocene. The invading species probably weren't E. kansensis or E. buisi.

My response:
The Rocky Mountains were around before the Old World species of Elaphe entered the New World. I agree that this species of Elaphe was around at the start of the Miocene. In fact, I said that it could have been around in the late Oligocene. Because most of the early to mid Tertiary faunal exchanges between Palearctic and Neartic occurred via the Thulean land bridge, I suggested that the ancestor of New World Elaphe also came this way. You disagreed and claimed that it came through the Beringia land bridge. I am glad you finally come around and agree with me that Elaphe could have been around in the early Miocene.

Terry wrote:
The fossil is from mid-Pliocene. That doesn't mean that the species only existed then. It probably died out at that time, and there weren't any other fossils of this old species.

My response:
I would not call Elaphe pliocenica “old.” That is an unsupported assumption. E. vulpina and E. obsoleta are older since both have been found in the late Miocene.

Terry wrote:
Sure, scientists base conclusions on evidence, but if they didn't ever speculate, how would they ever develop theories.

My response:
Of course scientists speculate, but they do so only when there is insufficient data. When there are facts, scientists do not speculate but must base their conclusions on known facts.

Terry wrote:
Ya know, I'll give you credit for coming up with the Thulean land bridge. I'm not going to say there isn't a chance that Elaphe ancestors came that way. I'm still thinking about it as a matter of fact. But I'm sure not going to put all my eggs in one basket and rule out all other possibilities. I think there's a good chance there was an Asian species crossing the Bering land bridge. I would even vote for an Elaphe schrencki or E. dione, if they weren't such young species.

My response:
I base my speculation on the distribution of New World Elaphe and water snakes. I had heard about a Europe-North America land bridge in the past but did not pay much attention to it. I only had vague memory of this land bridge when I started our discussion. There is of course the possibility that another species of Elaphe either came across the Thulean or even Beringia land bridge, and Elaphe flavirufa may well be this species. The other species of North American Elaphe no doubt are closely related, along with their close relatives in Arizona, Pituophis and Bogertophis. The Thulean land bridge is not well known even among scientists but several recent papers should change that. These papers show that some mammals, many plants and many groups of animals (including turtles) migrated through this route.

Terry wrote: I don't know why you insist that E. obsoleta could be the Elaphe ancestor from Eurasia. This is a late Miocene species that is still alive today and well adapted to the modern world. And E. buisi was an older species. I doubt seriously obsoleta could have evolved into that species.

My response:
E. buisi is NOT older. It is early Pliocene Oklahoma in distribution. E. obsoleta is late Miocene and farther north in Nebraska. E. obsoleta is close relative of the older E. kansensis, which is possibly conspecific with E. obsoleta, considering the fact that intraspecific differences in vertebra can be quite extensive within a species.

Terry wrote: Are we to believe Utiger et al. are like god on all the other species they tested and not even close with Senticolis? I understand why you don't like the placement of Senticolis, but according to the molecular data of Utiger et al., Senticolis is closer to the Lampropeltini than E. scalaris is. If I'm going to use their data as evidence of branching order, I have to consider where they put Senticolis. And if Senticolis is a racer, why doesn't it branch closer to the racers, or even Ptyas, then to the Lampropeltini?

My response
Some of their nodes are better supported than others. The node where they place Senticolis has a bootstrap value of 30. That is dismal statistical support and indeed, protein electrophoresis data places Senticolis outside of Elaphe (Old World and New World). So this part of their tree is not only weakly supported by their data, it is contradicted by other people’s molecular data and by morphology (hemipenial structure and intrapulmonary bronchus for example). The systematic position of E. mandarina is supported by earlier findings and by Tong et al. (Acta Zoologica Sininca) so this part of the tree is more robust. Utiger et al. find E. scalaris basal to New World Elaphe. The same finding has been obtained earlier by Lopez and Maxson. If multiple independent studies arrive at the same conclusion, the chance that it is close to scientific truth increases. If there is weak support and multiple independent studies contradicting the placement of Senticolis near the Lampropeltini, then it is probably not a part of the Lampropeltini.

Terry wrote:
Obviously, this is not the last word on Senticolis, and as we've said before, more testing needs to be done. Of course, I have another reason for responding to your Senticolis statements. I don't think we know enough about how the Southwestern U.S. and Mexican species have evolved. That will take some more research.

My response:
I welcome more studies on Senticolis. Both Utiger et al. and Rodriguez-Robles seem to have the preconception that this species is part of the Lampropeltini and they both prefer trees that show such a relationship. An author who is more objective may be able to determine the true affinity of Senticolis. Personally I do not care whether it is a racer or a ratsnake. I just want to find out which of this group it actually belongs. It appears to me that it is almost certainly not a ratsnake (not closely related to any of the 30 odd species of Old or New World Elaphe)

Terry wrote: As long as we're speculating here, how come you didn't include E. schrencki, or for that matter E. dione, as possible ancestors for the Lampropeltini? Actually these species seem to resemble New World Elaphe very closely, and I remember my first look at schrencki and thinking it looked just like Lampropeltis g. getula. I don't think E. scalaris could be the Elaphe ancestor of the Lampropeltini. Since the Thulean land bridge broke up by the early Miocene, the ancestor would have had to have been on Iceland by then, and scalaris is way too young for that.

My response:
Sorry it is not speculation but multiple independent studies which show E. scalaris as the closest relative of New World Elaphe and the lampropeltine genera. You keep insisting that E. scalaris is too young but you have no data to support that claim. E. scalaris comes out both basal and closest to the New World Elaphe in both Utiger et al. and Lopez and Maxson’s independent studies. Lenk et al., which use Lampropeltis as the outgroup(!) for their analysis of European ratsnake relationships, find that E. scalaris is the closest species to Lampropeltis triangulum. Even a weird analysis like Lenk et al.’s, which use a derived species of the Elaphe clade (L. triangulum) as the outgroup, still comes out with E. scalaris closest to Lampropeltis.

Terry wrote:
The Elaphe ancestor could have entered the New World from Iceland in the Miocene, but would have been an archaic Elaphe, not scalaris, or a scalaris ancestor.

My response:
E. scalaris is pretty “archaic.” It is basal not only to New World Elaphe and the lampropeltine genera, it is also basal to a large number of other Elaphe species, if you look at Utiger et al.’s tree more closely.

Terry wrote:
Another possibility is that the archaic Elaphe ancestor was E. kansensis, E. buisi, or E. pliocenica, which may have been a Eurasian species also. I don't know anything about the Eurasian fossils, yet, but it sounds like a future project.

My response:
E. buisi and E. pliocenica, your “pet” fossil species, are simply not old enough to be ancestral to New World Elaphe. As for European fossils, good luck with them. Perhaps you can prove that E. scalaris is a young species but it is not a good idea looking for fossil evidence, because Miocene age E. scalaris just may turn up in your search. Your best bet is molecular data. A young species has very little genetic variation among different populations. An old species has a great deal of intraspecific genetic variation. Elaphe obsoleta has a great deal of intraspecific genetic variation. It is an old species.

The Thulean land bridge had likely already broken up too much by the Oligocene for any snakes to cross it (see my last post below about the land bridges). Also, if E. scalaris was the ancestor of the Lampropeltini, then it would likely be the ancestor of the Elaphe too, that group with the Lampropeltini (Utiger et al). And that's very unlikely. A taeniura/moellendorffi ancestor is an older candidate and is more likely to have given rise to the other Elaphe. I believe taeniura, moellendorffi, and scalaris should stay in the Elaphe, btw, not be split to new genera.

Terry wrote:
The Thulean land bridge had likely already broken up too much by the Oligocene for any snakes to cross it (see my last post below about the land bridges). Al so, if E. scalaris was the ancestor of the Lampropeltini, then it would likely be the ancestor of the Elaphe too, that group with the Lampropeltini (Utiger et al). And that's very unlikely. A taeniura/moellendorffi ancestor is an older candidate and is more likely to have given rise to the other Elaphe. I believe taeniura, moellendorffi, and scalaris should stay in the Elaphe, btw, not be split to new genera.

My response:
As I pointed out in the reply to that other post, the paper you cited suggests that the land bridge between Iceland and North America may have remained passable until the Miocene. Therefore any ratsnake which may have been living in Iceland at that time (when Iceland was a warm temperate region) would have been able to migrate to North America until at least the end of the Oligocene. Besides, the Bering land bridge was not as passable during the early to mid-Tertiary. Yes, Lampropeltis and New World Elaphe share a common ancestor. This is pretty much established fact. This ancestor is most probably Elaphe scalaris or its direct descendant living in Iceland at the time the Thulean bridge was still open. Biogeographically it makes sense. It is also supported by mtDNA data, which shows E. scalaris basal to New World Elaphe. Morphologically it also makes sense since E. scalaris resembles B. subocularis, Pituophis melanoleucus and Elaphe obsoleta in color pattern.

BTW, I do not oppose removing species from Elaphe and placing them in other genera. I can be convinced if there are good reasons to do so. The first good reason would be polyphyly. Dowling and his colleagues removed Senticolis and Gonyosoma from Elaphe because these species are not closely related to other species in Elaphe. Not removing them would render Elaphe polyphyletic. I support these proposals. Senticolis and Gonyosoma have stood the test of time. They are valid genera. The second good reason for removing species from Elaphe is morphological disparity. Dowling and Price were able to show that Bogertophis subocularis and B. rosaliae are morphologically disparate from Elaphe, Pituophis and Arizona. This genus, too, has stood the test of time.

Utiger et al., however, splinter Elaphe beyond recognition without any justification because they can neither show that Elaphe is a polyphyletic group nor could they show that its members are morphologically disparate. Without any good reason, it is scientifically untenable and too destructive to splinter Elaphe the way they did.

Hi
Wauoh This is a question, I have asked myself many times. What is scalaris actually closest related too. I am a breeder and keeper of animals Not scientific. After working with scalaris for many years I noted some differences to the other european ratsnakes:
1. Head shape
2. 2 instead of 4 dorsal stripes on adults
3. Time of incubation
4. Prefered temperature in terrarium

When I look at them I think of Pituopis and Arizona. Why is that? They live in another part of the world and is it related to the similarities Chondropython and Caninus. But still they are so similar. Placing them different form the other europeans is understandable, but I would like to see the similarities with the 2 american species.
Best wishes
Søe

Reptilia - Denmark

Elaphe scalaris is the closest relative of New World species of Elaphe (such as E. obsoleta and E. vulpina) and to Pituophis, Bogertophis and Lampropeltis according to several independent studies using biochemical techniques.

RS, wouldn't the New World ratsnakes, Lampropeltini, be descended from the same ancestor as the Old World ratsnakes that Utiger et al. place in their "new" Elaphe (quatuorlineata, schrencki, dione, etc.)? That would make the Lampropeltini closely related (or sister group) to the Old World Elaphe (revised). Scalaris could be the ancestor, but we should look at that with caution, because scalaris could have come from the ancestral Elaphe, same as the others I'm talking about. Scalaris could be an earlier offshoot from the ancestor, same as Oreophis porphyracea, which is clustered with scalaris (Utiger et al.). My theory is there's an archaic ancestor, such as (Homan's, 2000) E. kansensis, which might have been holarctic. Just my 2 cents. Thanks...TC.

>>Elaphe scalaris is the closest relative of New World species of Elaphe (such as E. obsoleta and E. vulpina) and to Pituophis, Bogertophis and Lampropeltis according to several independent studies using biochemical techniques.