These are two out of many "tested at the creek" and "approved by trout" flies. The midge APE is a surface dry-fly pattern and APE stands for Adults, Pupa, and Emerger. Indeed this can imitate either one or anything between of three stages at the same time. Pupaerger is the made-up term of Pupa + Emerger. I can't emphasize enough how effective this pattern is on midging trout. Sooner or later, Pupaerger will be approved as an official English word and be added to the Oxford Dictionary! I have been using both in black, as black is the most common midge color on the Livingston's spring creek and many other waters.