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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.

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.
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Saddle-case Makers

This common name refers to only one family. Click its scientific name to learn more.

Caddisfly Family Glossosomatidae

These are often called Saddle-case Makers.
This family is one of the primitive caddisflies of the Rhyacophiloidea superfamily. However, they are not free-living like their better known cousins the Rhyacophilidae (Green Rockworm). Instead they build rounded "turtle" shaped cases that do not surround the larvae but are rather attached to the rock surface at their margins. Underneath is a sling made of secretions upon which the larvae ride, hence the common name Saddle-case Makers. There are four genera of possible interest but only one is generally recognized as important to anglers. See Glossosoma (Little Brown Short-horned Caddis) for details. The other three are so tiny that they are also called Pseudo-microcaddis.

Protoptila (Tiny Spotted Short-horned Caddis) is rarely important in trout streams and is generally found in warmer, larger water than the other two genera.

Agapetus (Tiny black Short-horned Caddis) is quite common in many northern streams.

Matrioptila is an extremely tiny southern genus.
Glossosoma (Glossosomatidae) (Little Brown Short-horned Sedge) Caddisfly Adult from the Big Thompson River in Montana
Dorsal view of a Glossosoma (Glossosomatidae) (Little Brown Short-horned Sedge) Caddisfly Larva from the Yakima River in Washington
I caught this tiny larva without a case, but it seems to key pretty clearly to to Glossosomatidae. From there, the lack of sclerites on the mesonotum points to either Glossosoma or Anagapetus. Although it's difficult to see in a 2D image from the microscope, it's pretty clear in the live 3D view that the pronotum is only excised about 1/3 of its length to accommodate the forecoxa, not 2/3, which points to Glossosoma at Couplet 5 of the Key to Genera of Glossosomatidae Larvae.

Saddle-case Makers

Scientific Name
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