The Stream Doctor

November 15th, 2004

Email YOUR Questions directly to the Stream Doctor. This is your opportunity to get an experts professional opinion on anything stream related.

Q. Concerning insects that fold their wings back, overlapping them (more or less) flat over the abdomen, is there a customary order in which they are folded, or is it simply happenstance as to whether the last (top) folded wing is a left or right wing? Sincerely, Roger

A. Roger, I'm going to give you a couple of pieces of information that I got from two stonefly taxonomists in response to your question.

Dr. Richard Bauman, BYU, told me that he was on a field trip with some students and they were observing a large hatch of Hesperoperla pacifica. As the insects crawled out of the water and began to emerge from their exuviae, the wings were held upright as they began to pump blood into them. When they were full, the insects seemed to 'stretch' the wings, and then folded them - the left one first and then the right one.

Dr. Ken Stewart, No. Texas Univ., sent me the following: "Aquatic insects that fold their wings over the back, such as Plecoptera, have defined fold lines. For the forewings, this is almost exclusively at the "anal fold line" between the cubital and anal longitudinal veins. For the hindwings, that are usually more complexly folded like a fan, there are several foldlines between longitudinal veins." Unfortunately, Ken didn't say anything about which side was folded first.

If you have a question, please feel free to contact me.
~ C. E. (Bert) Cushing, aka Streamdoctor
105 W. Cherokee Dr.
Estes Park, CO 80517
Phone: 970-577-1584

The 'Stream Doctor' is a retired professional stream ecologist and author, now living in the West and spending way too much time fly-fishing. You are invited to submit questions relating to anything stream related directly to him for use in this Q & A Feature at

If you would like to comment on this or any other article please feel free to post your views on the FAOL Bulletin Board!

Previous Stream Doctor Columns

[ HOME ]

[ Search ] [ Contact FAOL ] [ Media Kit ] © Notice