Reptile & Amphibian Forums

It's a mottled Drymarchon melanurus rubidus AKA; Mexican west coast indigo or Mexican red-tail indigo.
For years I have been keeping an eye on zoological data bases in an attempt to keep up with what members of genus Drymarchon are being maintained within zoological institutions around the world. I was shocked to find that only a single D. m rubidus was listed, though happy to hear it was being held at the Gladys Porter Zoo in Brownsville, TX. Upon this discovery, I immediately contacted Colette Adams, herp curator of the Gladys Porter Zoo, with an offer to donate a female D. m rubidus, as I felt it a shame the only specimen being held within a zoological institution worldwide should not have a suitable mate and besides, I donate at least half of the offspring my Drymarchon collection produces each year to a variety of institutions, though this was a first with the D. m rubidus.
Colette promptly contacted me and after a bit of correspondence and photo sharing, it was decided that the male would be better suited within my collection, as I already have multiple breeding projects in place, involving D. m rubidus, and the zoo has plenty of other herp related projects on their plate, including Cyclura. n lewisi, Crocodylus rhombifer (perhaps the most threatened of the new world crocodilians) and Crocodylus mindorensis (another crocodilian on the brink of extinction).
I have been trying to obtain permits to collect D. m rubidus in Mexico for several years now, only recently making any headway, as the species is the rarest in captivity, though fairly common along the Western coast of Mexico. The captive gene pool is EXTREMELY shallow, even more critical than D. couperi, so it is our hope this guy will help bolster the gene pool of captive D. m rubidus.
I must thank Colette and the Sr. herp keeper of the Gladys Porter Zoo, Dave Martin, as they have been incredibly helpful and most generous with their time and resources…
There you have it and I hope that if any of you are ever in South Texas, you will take the time to visit the Gladys Porter Zoo, as the work being done there, in regards to herpetofauna, is nothing less than incredible…

Best regards,
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Jeff Snodgres
University of Arkansas
snodgresjeffreys@uams.edu
501.603.1947

Jeff - so tell us what you know about where the mottled specimen comes from; is it a local morph or what ? I know rubidus varies alot, but is the variation geographic ? The southern end of rubidus' range approaches that of D.m. unicolor - maybe there's intergradation that produced the mottling on your animal ?

I've been toying with the idea of placing some of my research questions for Drymarchon taxonomy on the forum and letting members have a say at what they think the most interesting questions are. I hadn't thought about looking at rubidus (because their geog. distribution seems well known),but maybe I should rethink that.

Craig

i was thinking the same thing that craig mentioned regarding possible uni blood involved. is that possible jeff?

From what I have gathered, coloration among D. m rubidus varies from locale to locale, with the mottling becoming more dominant the further south you go into their range.
I have been given contact information for an individual who collected D. m rubidus for the export trade, back when it was legal to do so, and hope to be in communication with him sometime next week. I have heard, from a very reliable source, specimens much like the one pictured are somewhat common in Colima, which I have been told is perhaps the Southern most extent of their natural range. If this is true, I believe such would leave out any chance of integration between D. m rubidus and D. m unicolor, as it is my understanding the range of D. m unicolor falls just short of the state of Colima. However, it is possible there could be some integration between D. m melanurus and D. m rubidus, which would further support their classification as a D. melanurus ssp..
I am hoping Chris H. will jump in, as I know he has seen and photographed several D. m rubidus, from various locales, in the wild.
Unfortunately, there is much work to be done in regards to Drymarchon in Mexico, Central America and South America. Personally, I would not be surprised to see many more changes to the taxonomy of the genus, should such an endeavor arise.
I plan to set aside some time and compare the phenotypic traits of the new specimen to those of other D. m rubidus within my collection. I will further examine such traits between the new specimen and D. m melanurus and D. m unicolor within my collection. I am certain it will take a bit of time to make the comparisons, as all of the snakes are quite large and active, typical Drys, but I will share my findings here on the forum once I have such.

Best regards,

Jeff
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Jeff Snodgres
University of Arkansas
snodgresjeffreys@uams.edu
501.603.1947

Jeff - thanks, that's useful info - there are many preserved rubidus in collections, including my own LA Cty NH museum. Colors don't show up well in pickled animals, but mottling would be very clear - so in theory I should be able to go through a few dozen rubidus from different locales along the Mexican coast and nail down the variation in pattern, and also whether rubidus and unicolor overlap at all, or how close they come to each other. A neat idea to pursue.

Craig

Hi Jeff

Nice snake for sure! Some of the forum readers may or may not remember a post I made a year or more ago concerning rubidus. I stated that none of the ones being posted looked at all like the ones we used to get back 35 years ago. I stated that they were all black snakes marked in more or less chevron-shaped crossbands of red and pinkish, often increasing in intesity towards the tail The bellies were apricot-orange or red, and the faces were heavilly suffused with reddish coloration. In other words, quite colorful snakes. The common name then was Red-tailed Indigo.

I recognised your photo immediately as a rubidus of the variety I am personally familiar with. Please, no offense to anyone as I have not examined any of your snakes in person. But, the rubidus I have seen posted here from American collections appeared no different (to me) than what Texas Indigos from a little ways into Mexico look like.

Don't flame me guys. I have no stake in this. But one thing that I'm sure of is that Jeff's snake is indeed a real rubidus quite typical of those I've collected and seen (many years ago) from along the west coast of Mexico mostly around Colima.

Cheers,

Terry

We need all of the information we can get. It has been my experience that there are actually three - four different phases of D. m rubidus, I prefer to call them Mexican west coast indigos, as only very few harbor noticeably red tail coloration.
There is quite a spread between the population of D. m erebennus that extend into Mexico, as such are confined primarily to the eastern half of the country, while D. m rubidus are restricted to the western portion. The phenotypic differences between D. m erebennus and D. m rubidus are easily recognized, even by the casual observer, as you simply will not find D. m erebennus with the clean, white anterior ventral and deep, patternless dorsal coloration of D. m rubidus. I am attaching two photos, the first being a typical D. m erebennus and the second being a typical un-mottled D. m rubidus. While there are some similarities, the differences are obvious, but keep in mind, both sub-species are highly variable in both captivity and the wild.
Also, I have been in contact with an individual who collected D. m rubidus from as far north as Sinaloa and as far south as Jalisco. He spoke of three phenotypic varieties and indicated there might be a fourth variation. Apparently, the specimens we see most often, here in the US, if you can actually say that about the species, resemble the specimen in the photo I have posted and what you have indicated as being phenotypic of D. m erebennus. He indicated that heavily mottled specimens, much like the male I posted earlier, were commonly found in the state of Jalisco, while yet another color variant could be found in between the two already described, in the state of Nayarit, which he described as being quite similar to red chinned D. couperi and I believe Phil Frank has posted a photo on the forum of such a specimen.
We all know several specimens of the same species and sub-species can be highly variable, as one only needs to look at our native L. g. getula to reach this conclusion. They might look different from one region to another, but they are all L. g getula, at least for now! ;0)
I am going to compare scalation between the four mottled specimens, now residing within my collection, with the scalation of the six non-mottled specimens I currently have. I will further compare such with the D. m erebennus residing within my collection and post my findings.
Personally, and I have posted this before, I believe there will be some expansion of the Drymarchon genus, once more work has been done in Central and South America For now, I believe we can safely say the white chinned indigos are indeed D. m rubidus …

Enjoy the photos!

Jeff

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Jeff Snodgres
University of Arkansas
snodgresjeffreys@uams.edu
501.603.1947

The first one ended up being the photo of a female D. m rubidus and the second is a female D. m erebennus..

Sorry for the confusion!

Jeff
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Jeff Snodgres
University of Arkansas
snodgresjeffreys@uams.edu
501.603.1947

Hi Terry and Jeff. Just got back in town. It would be nice if the both of you could work together to re-establish the high contrast Rubidus. Terry, you might have some photos? Memory? A field trip or two to Mexico might help, I'm in............Bill
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"Life without risk is to merely exist."

Will you be in the Bend this year? I may be there for the New Moon in June my calinder says 23 through 30 but my scedual is kinda crazy...........Bill
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"Life without risk is to merely exist."

I've said this in the past, but of the 6 rubs I've had both black and mottled, the best name would be white throated indigo to me..You can see from the pics Jeff posted, even the new brightly colored male specimen has a very white/ivory colored throat..
What say yee??
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Carl W Gossett
Garage Door Herps
Monument,Colorado...northern territory of the Great Republic of Texas

The common name for D. m rubidus, as used among scientific circles, the AZA and ISIS is Mexican West Coast Indigo.

Best regards,

Jeff
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Jeff Snodgres
University of Arkansas
snodgresjeffreys@uams.edu
501.603.1947