Salmonflies
Pteronarcys californica
The giant Salmonflies of the Western mountains are legendary for their proclivity to elicit consistent dry-fly action and ferocious strikes.
- The prosternal horn is present.
- The mandible is clearly toothed, not formed into a uniform scraper blade.
- The seems to be only 2 major setae on the ventral edge of the hind femur.
- Chloride epithelia seem to be absent from the dorsal side of any abdominal segments.
Based on these characteristics and the ones more easily visible from the pictures, this seems to be Grammotaulius. The key's description of the case is spot-on: "Case cylindrical, made of longitudinally arranged sedge or similar leaves," as is the description of the markings on the head, "Dorsum of head light brownish yellow with numerous discrete, small, dark spots." The spot pattern on the head is a very good match to figure 19.312 of Merritt R.W., Cummins, K.W., and Berg, M.B. (2019). The species ID is based on Grammotaulius betteni being the only species of this genus known in Washington state.
Mayfly Species Choroterpes inornata
Species Range
Physical description
Most physical descriptions on Troutnut are direct or slightly edited quotes from the original scientific sources describing or updating the species, although there may be errors in copying them to this website. Such descriptions aren't always definitive, because species often turn out to be more variable than the original describers observed. In some cases, only a single specimen was described! However, they are useful starting points.
Male Spinner
Wing length: 7-9 mm
This is a blackish species with brown wing-roots and grey abdomen. Head blackish above with the tips of the antennae paler. Prothorax rufescent brown, very broad and with a broad quadrangular middorsal excavation of the hind lobe. Synthorax shining black, paler before the wing roots and around the leg bases. Legs all brown, darker on the front femora of the male. Wings subhyaline, with a darker costal strip due to the dark brown coloration of the first three longitudinal veins. The membrane is brown at the base, dark brown in the humeral cell, and faint for a distance beyond it. Cross veins very faint, even in the stigmatic area.
Abdomen dark grey, darker and brownish on the end segments, dirty white beneath. The paler middle segments are narrowly white across their joinings, and a very faint pale hair-line traverses them mid-dorsally. There is a row of minute blackish marks on the spiracles.
Start a Discussion of Choroterpes inornata
References
- Merritt R.W., Cummins, K.W., and Berg, M.B. 2019. An Introduction to the Aquatic Insects of North America (Fifth Edition). Kendall/Hunt Publishing Company.
- Needham, James G., Jay R. Traver, and Yin-Chi Hsu. 1935. The Biology of Mayflies. Comstock Publishing Company, Inc.
Mayfly Species Choroterpes inornata
Species Range
Resources
- NatureServe
- Integrated Taxonomic Information System
- Global Biodiversity Information Facility
- Described by Eaton (1892)