Reptile & Amphibian Forums

does anyone have any good links on identication characteristics of thayeri and mexicana? i have been lucky enuff to get a pair of snakes that look like they could be either one or the other. any help would be great. thank you.

First of all...What was the pair sold to you as?
And I take it you want to know if you have Lampropeltis mexicana thayeri or Lampropeltis mexicana mexicana?
These are two species that make up the mexicana complex....the other recognized species is the Lampropeltis mexicana greeri. At one time Ruthveni and Alterna were grouped with mexicana but has since been removed even though I disagree with that move.

Thayeri are also known as the variable kingsnake due to the ability of their genes to produce many pattern and color variations. As you may know their are milksnake phase thayeri, leonis phase thayeri (in many different colors) and melanistic thayeri (solid black). Most thayeri have a neuchal blotch.

Mexicana aka Mexmex have a grey (from light to near black) ground color and reddish orange saddles that may or may not reach the ventral scales. Mexmex also have a characteristic "tri-dot" pattern atop their heads and a small stripe down their neck or neuchal.

The best way to actually know what you have is to post a pic and get a reply/response to your pic. If you cannot post them email them to me and I can help you out.
Also, check out the Mexicana subforum. You will be able to see numerous pics of all Mexicana...You could possibly identify your snake that way.

John Lassiter
Here is a pic of Mexmex (L. m. mexicana) variation....

And here is a shot that should give you an example of Thayeri variation.
These are 2003 siblings (clutchmates).
John Lassiter

im setting up a page for u to view. i will be posting pics with labels, the only ones im not quite sure of r the ones labeled mexicana. i am almost sure but they look very similar to some thayeri i have seen. thanx for ur feed back. they will be posted shortly.

here are 2 pics of what i think are mex mex. tell me what u think. thanx for ur help.

Image

this thing is wearing on my nerves.....lets try this


Image

I believe them both to be Mexicana mexicana. You have an example of a dark phase (this post) and a classic phase (pictured in other post). Are they both females? Or did you buy them as a pair 1.1?
John Lassiter
Here is a pairing for me this year....a Splitbanded light male and a dark phase female....

I think you're right about the 1st one but the second one..........,????? Are you sure that 2nd one is a mex mex. Maybe a better pic. I'm not at all sure from that pic that the 2nd one is a mex mex. It looks like it could be a X.

A better pic could possibly help, especially a close up of the head. It does have some unusual aberrant saddles and it is lacking a neuchal stripe. I see no Thayeri in it. The saddles are characteristic of Mexmex. The dark ground color is Mexmex-like as well. I would like to see a head shot to be sure.

Chris,
What do you think it could possibly be crossed with? I have never seen Thayeri so dark. I have seen Greeri almost as dark. Most first generation Mexmex X Thayeri crosses look more Thayeri like, but I have not seen tons of them. But I am sure second and third generation crosses are out there.

I guess it all boils down to trusting your breeder. If there is any doubt questions should be asked.
John Lassiter

on the 2nd pic and it will take you to tatnu's photo gallery. There's a little better pic on page 3 of his gallery. The way the saddles wrap around the body on that snake is not characteristic of most mex mex I've seen. Most mex mex the saddles are pretty much on the dorsal and don't wrap around the body like that. Plus the abberant saddles that you mentioned. I DO think that its is a least part mex mex. I guess its even possible that its pure mex mex too but I have some doubts. The head does look mex mex but the neuchal saddle doesn't.

If I was forced to guess what it's crossed with I would guess a dark altera, blairs phase, or possibly a greeri. I agree that it doesn't look much like a thayeri cross but it might be and just have alot of mex mex influence.

n/p

I cannot find a page two but have looked at his pics in the kingsnake photo gallery.
I have a few mexmex that have their bands/saddles all the way to the ventral scales.
What I do notice is that tatnu's dark mexicana has wide saddles, but I have a classic looking mexmex that has similar sadles but they do not reach the ventrals.
Tatnu's mexicana could be just a variation of mexmex and not a cross. I still have not seen a good head shot and the lack of a neuchal stripe is a little concerning.

Here is a pic of my dark phase male. He has many of his saddles all the way to the ventrals.
John Lassiter

And here is an example of a "classic" looking mexmex. He has the wide saddles I was referring to and the characteristic "skull" or tridot pattern on his head.
Some of his saddles reach the ventrals as well.
I am still not sure about tatnu's dark mexicana but I could see more mexicana mexicana than anything else....
John Lassiter

I just looked at all your pictures. You do have a fine collection of reptiles. May I ask you...Did you acquire your collection of thayeri and mexicana from someone else or did you produce any of them? If you did not produce them, may I ask who did?
Are any of them siblings to one another?
Out of all your thayeri and mexicana pics I would only question two of them. One being the dark mexicana and a milksnake phase thayeri that looks a little mexmex to me. The others are beautiful thayeri. There are even a couple I would not mind having in my collection....LOL
Take your question over to the Mexicana subforum...You will get a better response from more people over there....
John Lassiter

well....my thayeri i purchased through kingsnake. i really cannot remember from who...ur name is very familiar...i purchased a large group.
anyway...i am sure that the ones u question are thayeri... definately for sure. i will post a pic of the head of the confused animal sometime this week when i have my camera at home. i apreciate all the positive input. as u can see...i was questioning that snake because it is definately a lil different. btw...they were purchased as mex mex a few years ago. i recently aquired them again after being stolen from me. now im looking to breed. so i want to be sure i am not Xing anything accidentally. thanx again.

If you go to the photo gallery and look @ jlassiter's or mexicanamak's photo gallery they both have really good pics of both thayeri and mex mex. Technically both L.m. thayeri and L.m. mexicana mexicana are in the mexicana kingsnake spp family. Thats probably why you are having some trouble IDing them.

Most mex mex have a gray background with red saddles. Most also have an extended nuchal saddle on their neck.

One of the other common names for thayeri is variable kingsnake. They variety is almost endless.

Can you post a picture? I'm sure several of us here on the forum can ID your snakes if you can post a pic.

Here is a fairly good representative leonis phase thayeri.