Common name for Crotalus ornatus and Crotalus molossus

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bgorum
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Common name for Crotalus ornatus and Crotalus molossus

Post by bgorum »

So I'm going through the unenviable task of cleaning up my keyword hierarchies in Lightroom. Normally I keyword photos with the common name of the species and then enter the scientific name as a synonym of the common name. This has left me with a dilemma where black-tailed rattlesnakes are concerned. Some of the my pictures with the common name black-tailed rattlesnake should have Crotalus ornatus as a synonym while others should have Crotalus molossus as a synonym. Are there yet officially accepted common names for these two species? I've seen Crotalus ornatus referred to as Eastern, Chihuahuan, and Ornate Black-tailed Rattlesnake. I've not seen anything in particular for Crotalus molossus.
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nhherp
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Re: Common name for Crotalus ornatus and Crotalus molossus

Post by nhherp »

I would go with the following for simplistic knowledge alone I think.
Northern Blacktail = C. molossus
Ornate Blacktail = C. Ornatus


I have seen hobbyist erroneously referring C.molossus as "mountain phase ??" and C.ornatus as "desert blacktail ?"
I do not understand why it's portrayed as a "phase" instead of its own species..

-N-
Jimi
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Re: Common name for Crotalus ornatus and Crotalus molossus

Post by Jimi »

SSAR uses Eastern (ornatus) & Western (molossus) Blacktail Rattlesnake. (That is intuitively satisfying to me.) Anyway, see their standardized-names database. Their 2012 pdf doesn't have ornatus yet.

https://ssarherps.org/cndb/

CNAH does this same thing, halfway - with them, ornatus is also "Eastern", yet molossus molossus is still "Northern" (???) in their pdf.

In my world SSAR is the more definitive authority. Other folks probably have different realities. Basically, you just have to pick, and deal with constant change no matter what. I wonder what HERP uses?

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bgorum
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Re: Common name for Crotalus ornatus and Crotalus molossus

Post by bgorum »

Thanks for the responses guys. Eastern and Western make sense to me and I also prefer the SSAR's spelling of black-tailed to CNAH's spelling of blacktail. Little things like that end up getting pretty messy. For example I have pictures labeled western diamondback, western diamond-backed, and western diamondbacked rattlesnake. Consolidating all of them is a pain in the you know what, but I've put it off way too long and it only gets worse with time. I'd love it if herp people could standardize on names, (though I realize that our understanding of the taxonomy of various groups will inevitably change), the way bird people have. I.e. a Northern Harrier is officially a Northern Harrier, even if part of me wants to call it a Marsh Hawk.
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The Real Snake Man
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Re: Common name for Crotalus ornatus and Crotalus molossus

Post by The Real Snake Man »

Eastern and Northern also technically makes sense because of the other Mexican subspecies of blacktail, which of course live further south. That said, western isn't bad.

-Gene
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cbernz
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Re: Common name for Crotalus ornatus and Crotalus molossus

Post by cbernz »

I didn't know about this split. So does this mean the Blacktails I've seen in TX and AZ are two different species? If so, I guess I get to add one to my lifelist!
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nhherp
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Re: Common name for Crotalus ornatus and Crotalus molossus

Post by nhherp »

cbernz wrote:I didn't know about this split. So does this mean the Blacktails I've seen in TX and AZ are two different species? If so, I guess I get to add one to my lifelist!
Yep. . New Mexico has both ornatus and molossus The division lies in south-western NM.

On the common name discussion , I guess I stuck with the originate common name of Northern Blacktail that was used to designate old C.m.molossus from Mexican BT's ~ C. nigrescens historically.

I do agree the Western and Eastern terminology does make more sense logistically.

-N-
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HERP.MX
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Re: Common name for Crotalus ornatus and Crotalus molossus

Post by HERP.MX »

"Eastern" would be a bit of a misnomer since there are populations of other molossus-complex snakes further east in Mexico. Regardless of what we call them, they sure are beautiful.

Here's an adult from near Cuatrociénegas in Coahuila, México
Image

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Jimi
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Re: Common name for Crotalus ornatus and Crotalus molossus

Post by Jimi »

Beautiful indeed. Would you guess that to be a Stockton clade animal, of ornatus? I sure love the silvery animals. Charming.

As for "places in Mexico that are east of the Edwards Plateau" - namely, from around the isthmus, eastward - the "molossus-mess" animals inhabiting that region would currently all be assigned to "nigrescens" or "oaxacus", yes?

My understanding of the former, from reading part of Anderson's dissertation, and all of the subsequent coauthored pub, is that it is cleanly, unambiguously, basal to several currently-recognized species (totonacus, molossus, ornatus, and - what was it, basiliscus? whoa, cool). So presumably, nigrescens will (pending a focused study) be elevated to full species & retain its common name +/- "Mexican blacktail"? Leaving a simple "eastern", "western", and "Mexican" set of common names referring to rattlers with black-colored tails?

And the latter...well who knows? Maybe oaxacus will just be rolled up into nigrescens as a clade, maybe something else...if something else I suppose it could just retain "Oaxaca" or "Oaxacan" somewhere in its common name...

Interesting stuff coming out. The species concept adopted by the authors (to wit, "looks like it's goin' this-a-way, all on its lonesome") has its appeal. Purists/ideologues will sniff, but we live in a messy world, eh? Ha ha. Categorical words & mentalities in a much more continuous molecular & phenotypic soup.

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regalringneck
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Re: Common name for Crotalus ornatus and Crotalus molossus

Post by regalringneck »

... we might need to save that term "western" for what surely must be yet another nigrescens, (to the splitters) ... i have my doubt's any of these are good stand alone sps.
Im referring to those nungly, invariably dwarfed "mojave green" looking little blacktails scattered on the most xeric piles of boulders from Phx on down to Yuma. Despite broad valleys creating apparent isolation, they are remarkably consistent in their appearance.
They appear to intergrade w/ the classic yellow BT's through much of the central portion of the state & there, these intergrades do often attain a fairly robust size.
Do the ornate BT's intergrade w/ the yellow subsps./phase to anyones knowledge?
Nigrescens is one of the most consistently "docile" snattlerakes in my experience.
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