Garter Hybridization

[Steven@HumboldtHerps]

Hello Everyone!

I am normally not into captive bred hybrid animals, but I am curious... Has anyone in the forum hybridized different species of garters? The reason why I am asking is because I live in a multiple intergrade zone. Humboldt and Del Norte Counties in NW California have 4 species of Thamnophis (sirtalis [fitchi & infernalis],elegans [elegans & terrestris], atratus hydrophilus, and ordinoides). Aside from intergrades between ssp., I am suspicious of some of the resultant "morphs". Many of the old school university heads are still stuck on maintaining the nomenclature, rather than reinterpreting what the definition of a species or subspecies should be. If there are any unusual patterns or colors, these are written off as variability within the species. I have, however come across too many specimens, where my gut tells me "this is a combo", a hybrid, and not an intergrade or a "morph". Gut feelings are not very scientific, but they are often the driving force behind new discovery; that's why I have gone back to school!

The attached photograph is of an apparent T. s. infernalis X T. e. terrestris. Typical of infernalis is the red head, 7 upper labials, unpatterned ventrals, and high-def red indentations (spots) pushing from the ventrals up into a black dorsolateral field. Classic features for terrestris vary; all however commonly have 2 alternating rows of black spots within the dorsolateral field, whether the background is brown, olive-brown, or partially, even completely suffused with red pigments; heads are normally olive to brown; 8 upper labials and red belly flecking are common; blue-gray bellied morphs occasionally exist, possibly influenced by Mountain intergrades. While not visible, red flecking occurred on this snake's caudal ventrals. More pictures of this specimen and others are viewable at HumboldtHerps.com (Natives Index)

Any experience you have had or word you have heard regarding hybridization ingarters would be highly appreciated, if it were sent my way.

Thank you,

Steven Krause

[adamanteus]

I have no experience at all of intergradation... I'm on the wrong side of the Atlantic. I would just mention that the red/orange flecking on the caudal ventrals is common to T. ordinoides as well.

[Steven@HumboldtHerps]

Yes, red flecking occurs in both ordinoides and e. terrestris, however this example was too large and did not have the typically small head of ordinoides. The pattern of this snake, although a bit chaotic, was nothing like all the ordinoides varieties that I have seen. I should also mention, that in this snake's case, the locale where it was found (Mad River near Arcata,CA) is a virtual Thamnophis jamboree! Here you find infernalis, multiple morphs of terrestris (w or w/o red flecking), one variation of ordinoides (possibly its southernmost range - I am working on this one with a local wildlife biologist in Crescent City; this Northwestern is a dull snake w/o red flecks.), and last Thursday we found an Oregon Garter (T. a. hydrophilus), which was probably swept downstream (these guys might also be migrating; they are amazing brutes!).

Sooo.... You can imagine my bafflement every time I stumble across these mixed pallets. Subspecies intergrades are usu. pretty obvious; it's the apparent hybrids that raise the eyebrows!

[adamanteus]

It sounds like a fascinating area you're in, Steven... obviously many more photographs are required from you!

[Stefan-A]

I can simply agree, the phenomenon of naturally occurring hybrids is very interesting, at least to me.

[Zephyr]

Have we ruled out the possibility of individual variation?

[Stefan-A]

I don't think it can be ruled out without genetic testing.

[Steven@HumboldtHerps]

Thanks for all your replies! What a great forum!

I do not think we can rule anything out. Individual variations (and there are a lot of polygenic phases!), subspecies intergradation, inter-special hybridization, dietary ontogenetic influences, incredible tendencies towards continual migrations in many species, & "Oh, no! Not simple recessive genes to boot! The list goes on.... and we human Thamnophis geeks are there to ponder the chaotic!

I should major in genetics!

[drache]

yeah
I wonder whether there are some species that are more likely to mix than others
curious to hear - and see - more

[Zephyr]

Thanks for all your replies! What a great forum!

I do not think we can rule anything out. Individual variations (and there are a lot of polygenic phases!), subspecies intergradation, inter-special hybridization, dietary ontogenetic influences, incredible tendencies towards continual migrations in many species, & "Oh, no! Not simple recessive genes to boot! The list goes on.... and we human Thamnophis geeks are there to ponder the chaotic!

I should major in genetics!

Could Stefan please translate?
I think he's speaking in Finnish...