Moved from Stoneflies. Thanks, Roger! I didn't collect this specimen, so further ID may not be possible...

Ken-

Your photos appear to be a female adult of family Capniidae, of which you have the following (57) species in California:

Bolshecapnia maculata (Spotted Snowfly)
Capnia barberi (Plumas Snowfly)
Capnia californica (California Snowfly)
Capnia confusa (Widespread Snowfly)
Capnia coyote (Coyote Snowfly)
Capnia elongata (Cascades Snowfly)
Capnia excavata (Saddleback Snowfly)
Capnia fialai (Humboldt Snowfly)
Capnia giulianii (Whitney Snowfly)
Capnia glabra (Smooth Snowfly)
Capnia gracilaria (Slender Snowfly)
Capnia hitchcocki (Arroyo Snowfly)
Capnia inyo (Inyo Snowfly)
Capnia lacustra (Lake Snowfly)
Capnia lineata (Straight Snowfly)
Capnia mariposa (Mariposa Snowfly)
Capnia melia (Northwest Snowfly)
Capnia mono (Mono Snowfly)
Capnia ophiona (Snakehead Snowfly)
Capnia palomar (Palomar Snowfly)
Capnia pileata (Birdhead Snowfly)
Capnia promota (Pacific Snowfly)
Capnia quadrituberosa (Four-knobbed Snowfly)
Capnia regilla (Royal Snowfly)
Capnia saratoga (Saratoga Snowfly)
Capnia scobina (Rasp Snowfly)
Capnia sequoia (Sequoia Snowfly)
Capnia shepardi (Yuba Snowfly)
Capnia spinulosa (San Gabriel Snowfly)
Capnia teresa (Bernardino Snowfly)
Capnia tumida (Swollen Snowfly)
Capnia umpqua (Umpqua Snowfly)
Capnia utahensis (Utah Snowfly)
Capnia valhalla (Viking Snowfly)
Capnia ventura (Ventura Snowfly)
Capnia yosemite (Yosemite Snowfly)
Capnura wanica (Rare Snowfly)
Eucapnopsis brevicauda (Shorttailed Snowfly)
Isocapnia abbreviata (Shortlimb Snowfly)
Isocapnia eichlini ()
Isocapnia grandis (Giant Snowfly)
Isocapnia mogila (Irregular Snowfly)
Isocapnia spenceri (Chilliwack Snowfly)
Isocapnia vedderensis (Vedder Snowfly)
Mesocapnia bakeri (Pomona Snowfly)
Mesocapnia bulbosa (Bulbous Snowfly)
Mesocapnia frisoni (Plains Snowfly)
Mesocapnia lapwae (Lapwai Snowfly)
Mesocapnia porrecta (Stretched Snowfly)
Mesocapnia projecta (Spined Snowfly)
Mesocapnia werneri (Sabino Snowfly)
Mesocapnia yoloensis (Yolo Snowfly)
Paracapnia boris ()
Paracapnia humboldta ()
Utacapnia columbiana (Columbian Snowfly)
Utacapnia sierra (Sierra Snowfly)
Utacapnia tahoensis (Tahoe Snowfly)

It may be possible for someone (other than me) to identify it to a lower level, but that would usually require microscopic examination of male genitalia.

Moved from ID Request.

Probably family too given the early date but I'm not great with identifying stonefly adults from images- perhaps Lloyd or Roger may help you further.