Terry,



There are those who don't consider the snakes in the Santa cruz river valley to be nigrita but only intergrades at best, simply because they think there is too much yellow in the pattern of juvenils and some adults. But these people are confused by the captive bred animals they have seen which have been selected for for many generations. Not only where the blackest wild animals selected but the blackest offspring are selected for future breeders. Throughout their range in Sonora where all agree it is pure in form one still finds just as many animals with lots of yellow splendida pattern as babies and many retain a lot of yellow into adulthood. As far as I am concerned the snakes from at least Green Valley south qualify as nigrita. Sure there is intergradation at the edges (on the north end of the Sasabe Rd. one can find hatchlings that when held in the light one can barely make out a "yumensis" pattern)Who knows what DNA would tell us. Perhaps nigrita is not even a valid sub, just a splendida that tends towards melanism in the S.W. portion of it's range.

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