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I recently got a Broad Banded that looks more like a Trans Pecos. How would one tell the difference? Thanx....

Although I personally feel that pictigaster is a very poorly-defined race (it was originally thought to be isolated in the mountains of west Texas), here are the currently recognized characteristics (from Dixon [2000]).

pictigaster - "Venter usually heavily mottled with dark color; subcaudals in males usually 57 or more, females usually 52 or more."

laticinctus - "Venter usually uniform tan or orangish pink, with or without a few dark markings; subcaudals in males usually 54 or fewer, females usually 52 or fewer."

The variation in subcaudals between the two forms is actually clinal: higher in the west to lower in the east. Apparently because of that, Roger Conant later on did not stress the use of subcaudal counts as a diagnosing feature between them.

He preferred instead to rely upon the dark ventral coloration (highly variable) and the supposed presence of a light-colored inverted "U" at the base of the dark crossbands to diagnose pictigaster. Unfortunately, this characteristic occasionally turns up in laticinctus from the southern portion of their range.

So, in summary, if you do not know the locality of your specimen, the subcaudal counts are probably the best character in attempting to separate these two subspecies.

Tom Lott

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What about the triads located laterally within the ground color of pictigaster? True, not all pictigaster exhibit this feature, but have you ever seen a laticinctus with these triads? Possibly on intergrades, but to my knowledge, not on true blue laticinctus. Additionally, the inverted U shape is also distinct to pictigaster. Any comments, anyone?

creep

I'm not sure what you mean by "triads." If you are referring to the tendency for the dark bands to be outlined with white, then no, I have not seen this east of the Pecos-Devils Rivers. However, I have seen a few Davis Mountain copperheads that did not display this feature either.

As far as the inverted "U" marking goes, I have seen a number of "true, blue" laticinctus that displayed this trait from around San Antonio (the southern end of the range). This is mainly on the anterior third of the body and on several occasions has been strong enough to be detected from the headlights of an automobile on the road. And, again, I have seen some Davis Mountain snakes that had the "U" marking poorly developed, if at all.

My main point is that these two races are so similar and with such a wide zone of intergradation (e.g., pictigaster from Edwards County?) that subcaudal counts are actually more reliable when the locale of the specimen is not known than are highly variable color and pattern characteristics.

Tom Lott