Header image
Enter a name
Lateral view of a Male Baetis (Baetidae) (Blue-Winged Olive) Mayfly Dun from Mystery Creek #43 in New York
Blue-winged Olives
Baetis

Tiny Baetis mayflies are perhaps the most commonly encountered and imitated by anglers on all American trout streams due to their great abundance, widespread distribution, and trout-friendly emergence habits.

Dorsal view of a Holocentropus (Polycentropodidae) Caddisfly Larva from the Yakima River in Washington
This one seems to tentatively key to Holocentropus, although I can't make out the anal spines in Couplet 7 of the Key to Genera of Polycentropodidae Larvae nor the dark bands in Couplet 4 of the Key to Genera of Polycentropodidae Larvae, making me wonder if I went wrong somewhere in keying it out. I don't see where that could have happened, though. It might also be that it's a very immature larva and doesn't possess all the identifying characteristics in the key yet. If Holocentropus is correct, then Holocentropus flavus and Holocentropus interruptus are the two likely possibilities based on range, but I was not able to find a description of their larvae.
27" brown trout, my largest ever. It was the sub-dominant fish in its pool. After this, I hooked the bigger one, but I couldn't land it.
Troutnut is a project started in 2003 by salmonid ecologist Jason "Troutnut" Neuswanger to help anglers and fly tyers unabashedly embrace the entomological side of the sport. Learn more about Troutnut or support the project for an enhanced experience here.

Identification: Key to Genera of Glossosomatidae Larvae, Couplet 4

Identification: Key to Genera of Glossosomatidae Larvae, Couplet 4

Adapted from Merritt R.W., Cummins, K.W., and Berg, M.B. (2019)
This couplet refers figures (usually designated 'sf') from this source.
You will need the source (make sure to get the same edition!) to see them.
Option 1Option 2
Basal seta of each tarsal claw long, thin, and arising from side of stout basal process (sf 19.163)Basal seta of each tarsal claw short and stout, larger than basal process (sf 19.162)
Case constructed with some relatively large stones (sf 19.167)Case constructed of uniformly small stones (sf 19.168)
WidespreadNorthwest, West
Protoptila Culoptila
The current couplet is highlighted with darker colors and a icon, and couplets leading to this point have a icon.
Leads to Couplet 2:
  • Mesonotum with 2 or 3 sclerites (sf 19.156, 19.157, sometimes hard to see)
  • Head with ventromesal margins of genae not thickened
  • Posterior median ventral ecdysial line about 1.5 times as long as each anterior divergent branch (sf 19.159, 19.160)
  • Anal opening without dark, sclerotized line on each side
Couplet 2
Leads to Couplet 5:
  • Mesonotum without sclerites
  • Head with ventromesal margins of genae thickened
  • Posterior median ventral ecdysial line about as long as each anterior divergent branch (sf 19.158)
  • Anal opening with dark, sclerotized line on each side (sf 19.60, 19.164)
Couplet 5
Leads to Couplet 3:
  • Mesonotum with 3 sclerites (sf 19.157)
  • Ventral apotome of head slender laterally, parallel-sided (sf 19.160)
Couplet 3
Leads to Agapetus:
  • Mesonotum with 2 sclerites (sf 19.156)
  • Ventral apotome of head not as slender, broader laterally than mesally (sf 19.159)
Leads to Padunia
(Padunia jeanae):
  • Each tarsal claw apparently trifid, with 3 points subequal in length (sf 19.161)
  • Southeast
Padunia
(Padunia jeanae)
Leads to Couplet 4:
  • Each tarsal claw with normal single point, basal seta and basal process much smaller (sf 19.162, 19.163)
Couplet 4
Couplet 4

You are here
Couplet 4 (You are here)
Leads to Protoptila:
  • Basal seta of each tarsal claw long, thin, and arising from side of stout basal process (sf 19.163)
  • Case constructed with some relatively large stones (sf 19.167)
  • Widespread
Leads to Culoptila:
  • Basal seta of each tarsal claw short and stout, larger than basal process (sf 19.162)
  • Case constructed of uniformly small stones (sf 19.168)
  • Northwest, West
Leads to Glossosoma:
  • Pronotum excised 1/3rd anterolaterally to accommodate coxae (sf 19.165)
  • Dome-like case of stones with transverse ventral strap of finer sand and interchangeable ends (sf 19.38, 19.459a, 19.459b)
  • Widespread
Leads to Anagapetus:
  • Pronotum excised 2/3rds anterolaterally to accommodate coxae (sf 19.166)
  • Case similar to that at left
  • West
Anagapetus

Start a Discussion of this Couplet

References

Troutnut.com is copyright © 2004-2024 (email Jason). privacy policy