Noticing small holes in a couple of my upper leaves

Does anything other than bugs cause small holes? I noticed a couple leaves getting a couple holes, but when i took my magnifier im not finding any bugs on the leaves or in the dirt. Could it be anything else?

It may be parasites. What strain do you have?

parasites? what the fuck. The strains i have right now are pitbull, galaxy god bud, and holy grail. transplanted into roots organic soil last week, young clones.

anyone else care to chime in?