Puget Sound Garters & polymorphism

[ConcinusMan]

In past posts I've shown some surprising variations (polymorphism) in WC red spotted garters (T. s. concinnus). Now its time to show some cool variations of T. s. pickeringii.

Sometimes the line between subspecies' outer appearance, and even their ranges, gets blurred. What is clear is that T. s. concinnus and T. s. pickeringii are on a genetic level, essentially the same snake. Their ranges even meet or perhaps overlap. The farther north you go out of concinnus' range, the more they start resembling fitchi or pickeringi. Likewise, certain pockets of pickeringi, especially near the Lewis County/Thurston county line, often resemble concinnus' or fitchi. If you didn't know where they came from, subspecies of T. sirtalis can be impossible to distinguish from one another visually.

Joe said something about this once or twice...

Subspecies... sometimes I wonder. I wonder about their validity or even the need for the splitting, particularly with western sirtalis'.

Sure, there are examples more "typical" of the pickeringi subspecies found in certain parts of the Puget lowlands, and there are "typical" concinnus' found in the southern Willamette Valley of Oregon, but that leaves a lot of miles of habitat for both subspecies, and a lot of snakes that just don't fit the subspecies descriptions neatly.

Like I said... If you didn't know where they came from, subspecies of T. sirtalis can be near impossible to distinguish from one another. With that said again, I'm calling these snakes (T. sirtalis pickeringi) Puget Sound garters (to me they're just way cool T. sirtalis') because I have seen all of these variations, and more, through out much of the pickeringi range I have explored, and likewise I've seen much variation in concinnus' even where ranges do not overlap.

Snakes like these (and these individuals pictured) are found from Dupont, WA , south to Olympia and as far as Chehalis, WA with much variation (even within a single localized population). I think that makes them pickeringi...

Doesn't it???

All T. s. pickeringi. From the Chehalis area to Tacoma, (and even beyond) you are likely to find any of these different looking ones:

Image colors are very close, if not dead-on accurate but I can't vouch for your monitor settings.

Female shedding: (Thurston Co.)

[ConcinusMan]

Like deja vu...

Laterally striped concinnus? fitchi? WT?

Range data suggests it could only be a pickeringi being how it was found near Tumwater, WA




More variations and pics coming very soon.

[katach]

Interesting Richard. I do know exactly just how variable the Pugets are. 2 of our 4 have no lateral markings, one has red, and the other has a very difficult to see green. It would be fascinating to get down to the DNA of it.

[BUSHSNAKE]

keep it coming....very cool!

[BUSHSNAKE]

More! More!

[mb90078]

You seem to imply integrading without using the word...

[-MARWOLAETH-]

Lovely pictures.

[ProXimuS]

I'm waiting impatiently for more pics/info!! Very interesting

[ConcinusMan]

You seem to imply intergrading without using the word...

Yeah, but is it primary, secondary, or both? I know that the area where concinnus and pickeringi ranges overlap or blur (Lewis County) was completely under water for thousands of years up until about 10,000 yrs ago. This, and glaciation at Puget sound, could have isolated a previously connected and continuous population of t. sirtalis, allowing them to evolve separately for a while. When the waters (glacial runoff lakes) finally receeded, they were then rejoined creating intergrade zones are the result of secondary contact between populations that were previously geographically isolated. This secondary contact very well could have happened, (happening now) but geographic morph variation within each subspecies' range, and DNA sampling suggest that the two have been in contact all along, with only intermittent periods of isolation. I could be completely wrong though and only extensive DNA sampling and years of research can reveal whats really going on with these two. I do know I read somewhere that it's nearly impossible to tell the difference between the two subspecies (concinnus and pickeringi) by DNA because they are essentially identical on a genetic level and I have to tell you, based on my interaction with them, they are the same. Everything I've always loved about concinnus' is there in pickeringi too. The only thing different is their color and pattern, and even that is nearly the same in certain individuals.

[ConcinusMan]

Another interesting thing to note is the dorsal stripe. The pickeringi subspecies is described as having a thin stripe. Not a bold wide stripe with well defined edges like all of these have.

A couple more:





These variations are neat and all, but it can get very frustrating when you've traveled 1500 miles looking for blues/greens and end up finding snakes that aren't much different than the concinnus' you've been getting for years, lol. I honestly didn't expect to see these though so its a nice surprise.