Alterna taxonomy question?

I have noticed alternas look very similar to the mexicana subspecies. For example the San Luis Potosi, L. mex. mex., has similar patterns and the alterna has varitiability like a thayeri. I was just curious as to how closely related they are mexicanas and alternas. Temperments and size are similiar also.

Is the alterna just a northern version of a mexicana ssp.?

Any repsonses to my curiousity would be greatly appreciated,
Uncloudy

Before they were elevated to full species status, gray bands were a subspecies of the mexicana group, Lampropeltis mexicana alterna.
I think the topic still generated a degree of debate in some circles.

Yes, and don't forget when they were actually thought to be 2 different species or ssp. depending on the time period. L.m. alterna and L.m. blairi. Some of the alterna phase ones can look very similar to some in the mexicana complex, but I think they are different enough to warrant species status. Course, I've always been more of a "splitter" than a "lumper"

You're right John, I forgot to mention L. m. blari .
While I don't support the division of alterna and blairs as subspecies, I do think the alterna should have their own species.
Then again, I'm still opposing the inclusion of Chondro viridis in the Morelia complex.

Thank you for the responses. I had a feeling they were more closely related taxonomic wise than what I preceived. Personally I think Lampropeltis mexicana alterna shoud be a subspecies of mexicana. Of course they could have different common names for separate locales, but for the sake of taxonomy and being genetically correct it makes sense to me that alterna should be part of the subspecies. It wasn't until I got a mex mex that I realized how similar they were. For 5-6 years I've been in this hobby I thought they were totally different like between a California Kingsnake and a Eastern kingsnake. A friend of mine emailed me this, "Alterna themselves were split into blairi and alterna until a gravid wild caught female had offspring showing both alterna and blairi characteristics. Now they are just Lampropeltis alterna (alterna phase, blairs phase and intermediates)."
I really like the mexicana spp. and I think buy having the alterna and ruthveni included would add to the mexicana subspecies credibility. I am easily confused at times so my preference would be to keep them together rather than splitting them up, but then again I could see both sides of the argument for or against. Again, thanks for the responses it made things more clear to me and I learned something.
Uncloudy

Is that the Isle of White?

I am pretty sure it's Isle of Wight, I need to go back and check the DVD concert. Either way it's a 1970 year photo. Some of the bootlegs I have CD are now being released, digitally remastered, but not complete like the Berkley show.
Rock On