This wild-looking little thing completely puzzled me. At first I was thinking beetle or month larva, until I got a look at the pictures on the computer screen. I made a couple of incorrect guesses before entomologist Greg Courtney pointed me in the right direction with Psychodidae. He suggested a possible genus of Thornburghiella, but could not rule out some other members of the tribe Pericomini.
Mysis shrimp also commonly known as opossum shrimp for the way they carry their broods, can be important to anglers as a curious bi-product of fisheries management practices. Fish and Game departments looking for a way to supplement the diets of planted kokanee salmon introduced these species from the Far North decades ago into many of the newly formed reservoirs. While not providing angling opportunities in the impoundments, they are often trapped in the dam's turbines and flushed down the tailwaters by the millions to feed the waiting trout. Their stunned or dead state makes them easy pickings. When these events occur the fish will really focus on them.
Mysida are not true shrimp and their appearance is unique. The species most commonly planted are virtually crystal clear transparant and they are more nymph shaped than shrimp shaped. Their legs are toward the front and they have a carapace that covers the head and thoracic segments. They also have appendages off the last abdominal segment that could be mistaken for tails. They have dark compound eyes.