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By Donny Benkendorf (@benkedonny on instagram)

There are 9 stonefly families in North America and all are beloved by trout! Keep reading to learn some highlights on each family.

As a quick taxonomy refresher, stonefly (or Plecoptera, which means folded wing in Latin) is a taxonomic order.

1. Within each order there are several families – for example, Perlidae (golden stoneflies) is one family within Plecoptera. All family names end in ‘dae’.
2. Within each family there are several genera – for example, Hesperoperla is one genus within the family Perlidae.
3. Within each genus there are several species – e.g., pacifica is a species within the genus Hesperoperla and the full species name is written Hesperoperla pacifica. The genus and species names are always italicized.

NOTE: All of the photos in this article were provided by fellow aquatic insect enthusiast Bob Hendricks (@buddhabob2hanlubo)!

Chloroperlidae (green stoneflies)

Species in Chloroperlidae are called green stoneflies because adults are often a vibrant green. Even the nymphs often have a dull greenish coloration. The bright green color makes it very easy to identify the adults, even from a distance. There are 13 genera (genera is plural, genus is singular) within Chloroperlidae.

Genus: Sweltsa nymph

Euholognatha (tiny stoneflies)

Euholognatha is actually an infra-order (a taxonomic grouping just below Plecoptera) that contains four families of closely related stoneflies. These stoneflies are Capniidae (winter stoneflies), Leuctridae (rolled-winged stoneflies), Nemouridae (spring stoneflies), and Taeniopterygidae (winter stoneflies). All four families are tiny and generally don’t get larger than half an inch long. These stoneflies also emerge into adults at highly variable times of the year including winter and early spring.

Genus: Taenionema nymph

Peltoperlidae (roach-like stoneflies)

This is probably the easiest family to identify because the nymphs really do resemble a stout-bodied roach. There are only 6 genera within this family.

Genus: Tallaperla nymph

Perlidae (golden stoneflies)

Many species in Perlidae are quite large, so if you find a really big golden-colored stonefly, there is a good chance it belongs to Perlidae. There are 15 genera in Perlidae.

Genus: Paragnetina nymph

Perlodidae (yellow stoneflies)

Species in Perlodidae are often confused with Perlidae because they often look quite similar. Perlodidae are often a little bit thinner and don’t look quite as robust as Perlidae. Many species in Perlodidae are also strikingly beautiful with alternating black and yellow patterning. There are a whopping 29 genera in Perlodidae!

Genus: Isoperla nymph

Pteronarcyidae (giant stoneflies)

In addition to being called giant stoneflies because the adults can grow to 2 inches long, Pteronarcyidae are also commonly called salmonflies because the nymphs and adults have a salmon pink/orange color on their underside. There are only 2 genera in Pteronarcyidae. The most famous species is Pteronarcys californica because it produces famously prolific hatches on western rivers.

Genus: Pteronarcys nymph