Well, the meristic scalation is virtually identical in both, so you really can't tell a leucistic Texas from a leucistic Black Rat when there is no visible pattern whatsoever. Some claim the heads are indicators, but individual snakes can have different shaped heads, this is just a fact. I guarantee there are lines out there that are a composite of both from people buying either type "labeled" as the other.



In certain parts of their ranges their normal phenotypic PATTERN can certainly look very different, but where the Texas gradually gives way to the Black Rat to the north and northwest, they can sometimes be impossible to discern. Certain Texas x Black intergrades of unknown origin are impossible too. Both can also have some yellow and reds to their underlying color scheme as well, but the Texas is far more noted for more coloration in the skin and/or scales than most Black rats, but some color can be expected to be greatly obscured by very Black specimens.



Texas Rats in the the northern Texas, Kansas, Louisiana, Oklahoma region fall into very substantial overlapping intergrade ranges of these two, and some think the Texas Rat is nothing more than a more southern clinal variant of the Black Rat. similar to what the "brooksi" is to the Florida kingsnake. All I can say is the Blacks from the extreme eastern portion of the country are visually different from the central and southern Texas snakes, but in many other parts you could almost call them either one. Having good range maps can certainly help IDing many of them properly, but others not so much at all to be honest.



Anyway, what I guess I am getting at here is that in more "pure" ranges, most of both these subspecies pattern and coloration can be easily noticed and identified, while others are just plain "head scratchers"..LOL!





~Doug
-----
"a snake in the grass is a GOOD thing"





serpentinespecialties.webs.com

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