Pteronarcys californica is a species of insect in the family Pteronarcyidae, the giant stoneflies and salmonflies.

Pteronarcys californica is found across western North America, from British Columbia to California.

Immediately prior to emerging, the nymphs congregate near the shoreline[4] in shallow water on partially exposed rocks.

About one month before emergence Pteronarcys californica nymphs start migrating from the center of the river to the shoreline making them more susceptible to predation.

To emerge, the nymphs crawl from the water to rocks or the shore, and split the nymphal exoskeleton.