Reptile & Amphibian Forums

I've read with some interest the debate here on hybridization. I have no strong opinion one way or another but thought those who hadn't seen it might want to look at one of the published journal articles on it about the Crots that have been the focus of the discussion:
http://links.jstor.org/sici?sici=0038-4909(19771015)22:42.0.CO;2-3

This is on JSTOR so my apologies to those without access.
The article is in the October 15, 1977 issue of the Southwestern Naturalist (vol 22, No. 4p 469-485). The conclusion of the article is that hybridization is not occurring in the areas where the species overlap although they acknowledge that there exists a captive-produced hybrid.

There may well be a lot more literature than this so please don't flame me if this is all old news to you guys! Just thought it was of interest and pertinent. BTW, it also lists the authors' criteria for distinguishing atrox and scutes.

By the way, noone has mentioned the Crotalus basaliscus-Crotalus molossus hybrids in southern Sonora-northern Sinaloa. Those are the best-looking candidates I've seen in the field but I profess no special knowledge and I cannot say that I took too close a look! They are very nasty and I prefer alternas...
2008 cheers to all,
Henry W.

I don't know how the tongue-wagging face got in my message! My apologies. I was not trying to poke at anyone.--HW

Hi Henry.

No flames at you from me

There certainly are other examples of what we have been discussing with other species. The real question comes down to is it plain old variation in these species or are hybridization events taking place out there? I have stated my beliefs.

As to the molossus X basiliscus hybrids you mentioned? Dare I say they are probably intergrades???

My best wishes to you in the coming year Henry.

Lastly, thanks to all the patient alterna folks who have put up with our drivel on your forum page!

Cheers, Hugh

I would certainly have no problem considering the molossus/basaliscus animals "intergrades." As I said, I have no particular set belief on this. Are we obligated to use the term "hybrid" if two separate species are involved? Is intergrade a synonym here? It all comes down to what is considered a hybrid. I've been out of serious biology long enough that I am not well-versed in such things anymore. Thanks for all the interesting thoughts on this matter, everyone. --Henry W

I was just poking fun and suggesting the idea that basaliscus and molossus might be conspecific? I have always wondered about that. Anyway, if they were the same species then the ones you brought up would be intergrades. As you mentioned or asked, when two different species breed and produce offspring, those babies are hybrids.

Cheers.

>>don't flame me if this is all old news to you guys!

Henry,
Damon and I are actually friends lol It's not hurting us to go a few rounds online. I'm sure we'll still be hashing this out a few years from now, and this summer if we meet up again. Besides, if you get flamed enough you either get fire-proof or burnt to a crisp lol.

>>By the way, noone has mentioned the Crotalus basaliscus-Crotalus molossus hybrids in southern Sonora-northern Sinaloa. Those are the best-looking candidates I've seen in the field but I profess no special knowledge and I cannot say that I took too close a look! They are very nasty and I prefer alternas...
>>2008 cheers to all,
>>Henry W.

On the basisliscus x molossus, I believe there is a strong case that they are conspecific, but that opinion is based entirely on literature and not personal experience. I've seen a crap load of nigrescens on the plateau, but none of the in betweeners at lowers elevations.
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http://www.hcu-tx.org

Oh I don't think there's any flaming going on ... I enjoy a good discussion and I'm glad there's secure folks like Hugh, Joe, and Frank that feel the same way.

Here are some other citations for you if you're interested...
Some are outdated but still contribute something to the topic. I have .pdfs of these if anyone wants copies.

Venoms and Morphology of Western Diamondback/Mojave Rattlesnake Hybrids
Steven D. Aird; Luke J. Thirkhill; Corrine S. Seebart; Ivan I. Kaiser
Journal of Herpetology, Vol. 23, No. 2. (Jun., 1989), pp. 131-141.

An Evaluation of the Possibility of Hybridization between the Rattlesnakes Crotalus atrox and C. scutulatus in the Southwestern United States
James S. Jacob
The Southwestern Naturalist, Vol. 22, No. 4. (Oct. 15, 1977), pp. 469-485.

Reproductive Activity of Male Crotalus atrox and C. scutulatus (Reptilia:
Viperidae) in Northeastern Chihuahua, Mexico
James S. Jacob; Stephen R. Williams; Robert P. Reynolds
The Southwestern Naturalist, Vol. 32, No. 2. (Jun. 15, 1987), pp. 273-276.

Crotalus scutulatus (Viperidae) in Jalisco, Mexico
Jonathan A. Campbell
The Southwestern Naturalist, Vol. 24, No. 4. (Dec. 10, 1979), pp. 693-694.

An Intergeneric Hybrid Rattlesnake
Reeve M. Bailey
The American Naturalist, Vol. 76, No. 765. (Jul. - Aug., 1942), pp. 376-385.

An Apparent Natural Hybrid Rattlesnake and Crotalus willardi (Viperidae) from
the Peloncillo Mountains of Southwestern New Mexico
Jonathan A. Campbell; Edmund D. Brodie, Jr.; David G. Barker; Andrew H. Price
Herpetologica, Vol. 45, No. 3. (Sep., 1989), pp. 344-349.

Analysis of Hybrid Zones
N. H. Barton; G. M. Hewitt
Annual Review of Ecology and Systematics, Vol. 16. (1985), pp. 113-148.

Rattlesnake Hybrids: Crotalus viridis × Crotalus scutulatus
Sherburne F. Cook, Jr.
Copeia, Vol. 1955, No. 2. (May 20, 1955), pp. 139-141.

PS... here's the image of the willardi hybrid from the Campbell, Brodie, Barker, Price paper. A= klauberi, B= hybrid, C= obscurus

I've seen that willardi x klauberi. Thanks for that.
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http://www.hcu-tx.org

THE ROLE OF HYBRIDIZATION AND INTROGRESSION IN THE DIVERSIFICATION OF ANIMALS

Thomas E. Dowling and ­ and Carol L. Secor ­

Department of Biology, Arizona State University, Tempe, Arizona; 85287-1501 e-mail: Thomas.Dowling@ASU.EDU , Secor@ASU.EDU
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http://www.hcu-tx.org

Glad to hear all that's been in fun. And by the way, I wanted to say hi to Frank -- its been a long long time. Frank: do you have any photos of alternas from Mexico? They could be anonymous as to collector or whether collected at all. I'm sure you know of some but don't know if you've been snapping photos.

And thanks, Damon, for putting that photo of the willardi/klauberi animal up. I ran across that reference but never looked at it. It is interesting that the pattern is so faded like obscurus.

And Joe (I think it was Joe), you are right, by now I should be flameproof given all the responses to some things I've said on the net! So what the hell, flame away! --HW

Henry, anyone that flames you deserves a backdraft! Keep on keepin' on!
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Todd Hughes

they intergrade - and they do it all over the west coast. They're the same snake - just a lowland form and a highland form.

-JJ