Sorry I "stole" your picture - It was just for comparison since you asked the question.
The lighter ventral area in your animal is nothing more than regional difference. My animal is an Eastern Kentucky animal. Dorsally, yours may be darker!
On the subcaudals of your morph –
Normal American Rat Snakes should have divided subcaudal scales from the vent to the tip of the tail. I wouldn’t be worried about your orange albino’s scales if they are a little different, as long as the animal seems healthy.
You probably know this:
Albino (amelanistic) animals in this hobby are started often from a single animal that has somehow had its color programming “corrupted”, for lack of a better word. This, of course, is extremely rare in nature, if the abnormal trait does not increase the survivability of the animal. Amelanistic traits do NOT increase the survivability of Black Rat Snakes, so it is very rare in nature.
Breeders find out if this trait can be passed on to offspring (heritable).
Very often the trait is recessive, meaning; the only way to get any albino babies is to breed two animals that contain the same type of recessive genes.
I’m trying desperately here to not get into a deep genetics discussion.
If you want more, a good place to start is:
http://en.wikipedia.org/wiki/Mendelian_inheritance.
http://www.saasta.ac.za/biosciences/genes.html
Along with the recessive trait that you and I may think is neat (albino), and want to breed for, there may be several undesirable recessive traits that may not be so obvious.
To breed for the one we want, sometimes we get the other recessive traits that we don’t want!
Maybe they CAN be seen (e.g. a frontal scale missing, exceptional small size, etc.)
Maybe these traits CAN NOT be seen (e.g. a small heart, a propensity for low resistance to disease, etc.)
Combine all this with the fact that breeding reptiles for a recessive color morph inherently means a large percentage of “in breeding”. While snakes seem to be much less sensitive to negative effects of “in breeding” than mammals, they are not impervious to it. Some really weird and bad things can pop up.
In short, when you buy a snake that is a recessive color morph, don’t be surprised if you get some extras that you didn’t realize you were buying!
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Regards, Bill McGighan
. I don't care at all though. I had 2 more questions about obsoleta subcaudal scalation.... I notice yours scales are jet black and mine are more of a glossy "smoke" color. Is this odd or a locality thing? Also notice the line starting at the cloaca that divides the subcaudal scales all the way down to the tip of the tail? My male orange albino does not have this... Does that mean anything?