Video: https://youtu.be/YqhYUM09aLI
This fellow was detected by my cat. Not much of a feat, really, as it was actually in plain sight in the meadow (photo 3). But I suppose a cat's eyesight works better than a human's, mine anyway, as I must have literally walked over it, not noticing it at all. I may actually have caused it to stir, thus triggering my cat.
I left the reptile by a large heap of dried grass, which it gladly disappeared into (photo 4).