I am still getting a handle on what constitutes a Stag Horn as distinct(?) from an Elk Horn, and as this is a juvenile, I’ll definitely leave that to more learned mentors!
This fern is one of a few which have colonized a shade cloth canopy. (The canopy collapsed a few years ago and a substantial amount of leaf litter has accumulated in the depression formed in the top, with several ferns & other plants colonizing the underside).