Midge larva, in various colors, can be very effective in the winter, and all year round actually. They are very simple to tie. Here is one, tied with fl.orange in a #16 for illustration, but #18 and #20 can often be better.
Back to the vise - 1st fly of 2025.
#14 thorax mahogany dun, dun turkey flat, grizzly hackle trimmed flat. Apparently lacking the signature Mashbill “ can’t get tippet thru the hook eye while mid-stream in fading light” feature.