Timpanoga hecuba

Adults have a reddish body coloration that distinguishes them from the green drake (Drunella grandis) and other mayfly species commonly encountered in western North American streams. The species can be differentiated from the common burrower mayfly (Ephemera simulans) by body color and size.

Nearctic region; North America.

Mayflies have an aquatic larval stage (nymph), followed by emergence as winged subadults (subimagos or duns) that molt once more into sexually mature adults (imagos). The subimago stage is behaviorally significant as these insects must rest on the water surface to allow their wings to dry before flight, making them vulnerable to predation.

Subimagos exhibit surface-resting behavior after emergence, remaining stationary on the water while their wings dry. This behavior makes them predictable targets for surface-feeding fish. Adults are short-lived and do not feed.

Important prey item for trout and other sport fish during emergence events. The predictable surface-resting behavior of subimagos concentrates energy availability for aquatic and riparian predators.

Significant target species for fly fishing; artificial flies imitate both adult and subimago forms. The species is referenced in fly-tying literature as the 'Great Red Quill' pattern.

• Ephemera simulansCommon burrower mayfly; T. hecuba differs in body coloration and is distinguished by its reddish hue.
• Drunella grandisGreen drake; T. hecuba differs in color (reddish vs. green) and is smaller.
• Hexagenia limbataHex mayfly; T. hecuba is smaller and has different emergence timing and behavior.

• mayfly
• Ephemerellidae
• fly fishing
• Nearctic
• aquatic insect
• trout prey
• subimago
• dun
• Great Red Quill
• western North America

• BugGuide
• GBIF taxonomy match
• iNaturalist taxon
• NCBI Taxonomy
• Catalogue of Life
• Teach a Man to Fish (and some entomology) and You’ll Feed Him for a Lifetime
• New butterfly species named after retired museum specialist