The only thing that surprises me about this is that it came as a surprise to the scientists. Most lizards are more than smart enough for the simple tasks described here and they demonstrate it regularly. I can't understand how anyone could imagine that lizards could possibly survive in the wild without the basic abilities to forage and adapt their behaviour to their surroundings. Did they really think they just moved forwards with their mouths open, accidently mated and died?
A key sentence seems to me to be the last in the lede: "The cognitive abilities of reptiles have rarely been studied." What we don't know isn't just more than what we know, it's for practical purposes infinite. The info-landscape is replete with things that haven't been studied simply because the number of people around to study things is mind-bogglingly overwhelmed by the number of interesting things they might study. There's just so much cool stuff to choose between.
One does wonder where the stereotype of 'stupid reptiles' came from. Unexamined pro-mammal prejudice, perhaps? (Biological class-ism?)
Something unclear from the article is what kinds of animals are known to not have the level of intelligence demonstrated by this study.
Yes. Biological class-ism! Who studies the cognitive abilities of reptiles, amphibians, insects, for example? Just the thinking abilities of mammals are studied. I guess everything else is supposed to operate on instinct.