Pteronarcys dorsata

[Alex C. 0]

I'm getting ready to tie one of these and want to learn more about them first. I found some pics and info on troutnut.com, but want to see pictures of different specimens, etc. Are their gills and leg hairs always white? Whats the mature nymph size range? Any good sites pertaining to them?

[Taxon 0]

Alex-

Are their gills and leg hairs always white?

I would describe the gills as a dull mustard at their base and pale yellow toward the tips, and the leg hairs as light tan.

 

What’s the mature nymph size range?

In his book, Nymphs, Ernest Schwiebert provided the following physical description of the (mature) Pteronarcys dorsata nymph:

 

Tails: Slate brown, 3/4 inch

Tergites: Black ringed with brownish gray, 7/8 inch

Sternites: Brown ringed with pale brown, 7/8 inch

Thorax: Back with brown joints, 5/8 inch

Sternum: Brown with pale joints, 5/8 inch

Wing cases: Black with pale joints, 1/2 inch

Legs: Black with brown joinings, 3/4 inch

Antennae: Slate brown, 1/2 inch

Head: Blackish brown, 3/16 inch

 

So, according to "Ernie's" measurements, the length, from front of head to tip of abdomen would be 1.685 inches (~42 mm.) However, I would expect the mature nymph length range to be 25 mm. to 50 mm. (1" to 2"). Hope this information proves useful.

 

[Alex C. 0]

Thanks Taxon, that will help alot :headbang:

 

 

What are Tergites and Sternites? I'm guessing they are abdominal segments?

[sandflyx 0]

Ernie based his on the Broadheads creek one I believe...

 

[Ethan Bright 0]

>What are Tergites and Sternites? I'm guessing they are abdominal segments?>

 

Terga and sterna are the dorsal (top) and ventral (bottom) scleritized plates of the insects thorax and abdomen. The thorax is divided into three parts - pro- (joins the head), meso-, and metathorax (joins with the abdomen). Each thoracic segment has a tergite, or top plate, and bottom sternite (or bottom plate). There are also side plates - pleura - that are often highly differentiated and with a cornucopia of terms. The abdomen is likewise divided into top, (often middle), and bottom plates. (There are pleura, but these are often greatly modified or not visible/or lost). Remember - insects incorporate incredible diversity and evolutionary history, so plates can may be fused, greatly modified, or lost.

 

Sandfly bob's picture - the stonefly nymph on the person's finger is most likely Acroneuria sp. (Perlidae). The adult is also not Pteronarcys, also a perlid, perhaps the same genus (but I can't make it out).

 

[sandflyx 0]

same water same stonefly i think, thanks Ethan, I'm only an amature, but studied under schweibert some..