Winter Baetis Mayflies can be very dark colored. Many are jet black. As the nymph swims to the surface the adult insect is already separating itself from the nypmphal shuck. Bright green bands form at each abdominal segment. As the skin splits down the back of the head and between the wing pads of the nymph, the dun starts to emerge through this tear. At this point, the insect can neither swim nor fly. It is completely helpless and a perfect target. Mark Bachmann pattern.
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