Drymarchon spp. and Naja spp. tend to exhibit some level of intelligence and, as has been mentioned, the two appear to be quite closely related; hence the reason Dr. Wolfgang Wuster coined Drymarchon "Honorary Cobras", as they “feel” much the same when handling, not to mention, there are a number phenotypic similarities between the two. I would also like to throw in Python reticulates, as they too appear to demonstrate a high level of awareness, which is often the behavior by which we measure the “intelligence” of serpents..
As for basing intelligence regarding feeding response, as someone mentioned earlier, Drymarchon spp. would win such a contest hands down, as there are few animals which harbor the feeding response of Drys, not to mention, they are rivaled only by varanids when it comes to diet, as they will feed on birds, rodents, reptiles (even turtles), amphibians and have been known to take road kill in the wild.
Also, as was mentioned, chelonians are quite intelligent, but there is some debate as to whether the intelligence of chelonians surpasses that of varanids.
An avid Drymarchon breeder shared an interesting story with me once; He explained how he was feeding one of his young D. couperi a live mouse, he said the mouse bit the snake on the head, when the snake seized the mouse by the side. I was told the indigo immediately submerged its head within the water bowel, mouse still clinging by its teeth, long enough to drown the mouse, and then promptly ate it. To me, this says something about intelligence. I further believe Spilotes pullatus could be amended to a list of “intelligent” snakes, as I have witnessed them constrict multiple rodents at the same time, then devour the rodents in the order they expired…
Best regards,
Jeff
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Jeff Snodgres
University of Arkansas
snodgresjeffreys@uams.edu
501.603.1947