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Artistic view of a Male Pteronarcys californica (Pteronarcyidae) (Giant Salmonfly) Stonefly Adult from the Gallatin River in Montana
Salmonflies
Pteronarcys californica

The giant Salmonflies of the Western mountains are legendary for their proclivity to elicit consistent dry-fly action and ferocious strikes.

Lateral view of a Male Baetidae (Blue-Winged Olive) Mayfly Dun from Mystery Creek #308 in Washington
This dun emerged from a mature nymph on my desk. Unfortunately its wings didn't perfectly dry out.
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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Western Stone

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

Stonefly Species Calineuria californica

These are very rarely called Western Stone.
Calineuria californica is the largest western species of the Perlidae family, with female adults approaching 40 mm in some locales. This species is perhaps better known by anglers under its former scientific name, Acroneuria californica. It is the primary Golden Stonefly hatch of the West Coast states, a role shared by Hesperoperla pacifica to a lesser degree. Their roles are reversed in the Rocky Mountain states where pacifica takes the top billing. Both are now commonly known as Golden Stones as regional colloquial differences have slowly dissipated. They were both commonly called Brown Willowflies in the Rockies and Golden Stones in the coastal states, which explains the confusion caused by references in older fly fishing literature.

This large stonefly is ubiquitous in western freestones and can provide incredible angling at ther height of their activity. On rivers lacking populations of Pteronarcys californica, they are the largest and most significant hatch of the year. They are generally a late spring/early summer emerger. They crawl out of the water to perch on streamside riparian foliage or rocks where they shed their nymphal shucks. They also mate in the same locations. The females end up back on the water in good numbers and offer good dry fly fishing. But it is the nymphs that offer the best angling opportunities, especially as they stage in the shallows in preparation for emergence.

The nymphs lack anal gills which easily separates them from Hesperoperla and Claassenia. Their lateral ocelli (simple eyes) in a pale background separates them from Doroneuria.

The male adults of Calineuria and Hesperoperla are easy to tell apart by looking at their hammers. Both are quadrangular but Calineuria is longer than wide. The heads and pronotums of both sexes are dramatically marked in Calineuria while Hesperoperla is more plain.
Female Calineuria californica (Perlidae) (Golden Stone) Stonefly Adult from Mystery Creek #249 in Washington
I caught this female in the vegetation on a trail about 50 feet above the stream. The coloration on its head differs from that of a male I collected recently on a nearby river, and from another female I collected on the same river. But it still keys out confidently to Calineuria, and californica is the only species of that genus in the area.
Lateral view of a Calineuria californica (Perlidae) (Golden Stone) Stonefly Nymph from Holder Creek in Washington
This striking golden stonefly is the first of its species I've had the chance to photograph.

Western Stone

Scientific Name
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