I think my succulent garden is being damaged by nocturnal insects, not snails. The insect eats a small circular spots on the leaves. These spots go brown when dry. I am reluctant to use insecticides as I have gekkoes in this garden. I was able to tolerate the damage until the most affected plants started dying. The stems begin to wither and the leaves of the plant stop growing.If I cut the plant off above the withered stem & replant it, it will eventually rejuvenate. The insects are more active through winter. I manually remove snails at night but I haven't been able to see what is doing this damage. Snails will eat chuncks of leaves, this damage is more like hail spots. I would like to know what the insect is so that I can look for it & get rid of it either by hand or with an insecticide that won't affect the gekkoes