Dark Rusty Spinners

This species is slightly smaller than Hexagenia limbata and it occurs later in the year. It is only mentioned in passing by a few authors, but it can be locally important.

Cinygmula reticulata is probably the second most important species of Cinygmula behind Cinygmula ramaleyi, perhaps because the waters where it can be found in good numbers are often more remote. They have been reported as abundant in many high country streams of the Southern Rockies as well as the High Sierra's Eastern slope. An obvious difference in their coloration may be the easiest way to tell them apart. Cinygmula ramaleyi is more somber with a brownish body and dark gray wings and is often confused with the similar sized and colored Ephemerella tibialis, in spite of the difference in tail counts. Cinygmula reticulata on the other hand is a bright cinnamon dorsally with pale creamy legs and pale wings that are often a brilliant canary yellow. This is one of North America's most beautiful mayflies.