Willowfly/Early brown/black stonefly
Taeniopterygidae
Summary 4
Taeniopterygidae are a family of stone flies with about 80 described extant species. They are commonly called willowflies or winter stoneflies and have a holarctic distribution.
Nymphs 5
Size: 9-12mm.
Body: Greyish brown or reddish brown to almost black, often with a lighter stripe running dorsally along the length of the body. The genus Taeniopteryx has finger like gills at the base of each leg, but other common genera (Strophopteryx, Taenionema, and Oemopteryx) lack this feature.
Legs: Solid black to brown. Second tarsal segment as long as the first ( this is a diagnostic feature for both nymphs and adults).
Wing pads: When mature, the wing case of Taeniopterygidae nymphs will make a wide, triangular shape and will be divergent from the length of the body.
Adults 5
Size: 9-12mm.
Body: Mostly brown/black, often with sclerotized areas of orange-brown.
Wings: Clear with dark venation.
Tails: Very short.
Adult Look Alikes 5
Nymph Look A Likes: Nymphs of the Taeniopterygidae stoneflies are most similar to those belonging to the Nemouridae family. Both families are early-season hatches, so emergences may overlap. However, Taeniopterygidae adults are significantly larger than are Nemouridae adults, the latter only ranging between 6 and 8 mm.
Habitat & Distribution 5
Taeniopterygidae can be found in stream and small river reaches of moderate to fast current speeds. While all genera listed earlier occur in central New England, their habitat preferences differ. Taeniopteryx is most tolerant of warm water and therefore can occur on downriver sections of larger streams and small rivers. Strophopteryx is also tolerant of warmer water and therefore relatively common in larger streams. Taenionema occurs in smaller to medium-sized streams, while Oemopteryx is generally confined to smaller and medium-sized streams.
LIfe Cycle - Emergence 5
Taeniopterygidae nymphs crawl out of the water to emerge from their nymphal skins.
Depending on the genus/species, this activity may occur as early as mid-winter or as
late as May. Taenionema is the latest to hatch among the four eastern genera treated
here. Egg-laying adults are said to make for good early-season fishing opportunities.
Nymphs hatch soon after egg laying and enter diapause (a sort of hibernation) from late
spring until fall, at which time they resume feeding and growing until winter/spring
emergence.
Degree of Difficulty 5
This table is meant to help users get an idea of how easy/hard it is to ID this species to any taxonomic level, and to give an idea of the characters (or features) that are important to accurately identifying a specimen. As a general guideline, these DD levels translate to the type of effort needed to reliably ID a specimen to that taxonomic level, as long as the associated features are confirmed. Of coarse there will/may be exceptions to these general rules.
Taeniopterygidae
Taxonomoic level
Taxonomic Name
Feature
Degree of difficulty
Order
Plecoptera
Wing Shape
1.5
Family
Taeniopterygidae
time if year/size/color are all important. Could be confused with early season perlodidae, but coloration should allow separation. the perlodidae are yellowish or at least lighter in color.
3.5
Degree of Difficulty
Degree of Difficulty
Description
1
Can be ID’d on the wing or water.
2
A specimen in the hand can be ID’d.
3
Can be ID’d by studying a decent photo of the specimen.
4
Can be ID’d by studying a captured & preserved specimen, usually under some magnification.
5
Proper ID requires study of preserved specimen under magnification, usually looking for some feature that can be difficult to confirm. Usually requires training or confirmation from a professional.
Sources and Credits
- (c) Andrew Cannizzaro, some rights reserved (CC BY), https://www.flickr.com/photos/acryptozoo/16744767045/
- (c) Jenn Forman Orth, some rights reserved (CC BY-NC-SA), https://www.flickr.com/photos/urtica/7062696195/
- (c) Jerry Schoen, some rights reserved (CC BY-SA), https://www.flickr.com/photos/79718069@N00/14123278936/
- Adapted by Jay Aylward from a work by (c) Wikipedia, some rights reserved (CC BY-SA), http://en.wikipedia.org/wiki/Taeniopterygidae
- (c) Jay Aylward, some rights reserved (CC BY-SA)
