Gray Drake

Family: Siphlonuridae

Genus: Siphlonurus

Life Cycle: incomplete

Three Life Stages: egg, nymph, adult cycle which includes 2 phases: dun and spinner

Emergence: April-October

Swimmer Mayfly Group

Nymph

Body Description

Antennae: 2, short

Abdomen: double-flapped gills on first segments

Eyes: large

Tails: 3

Wings: pads

Legs: 6

Mobility: hair fringed tails make them rapid swimmers

Most dense populations are found in slow-moving streams. They can be found among the grass and roots of undercut banks. Diet includes plant matter, smaller insects but mostly midge larvae. Trout can get fat feasting on these nymphs.

Dun

Duns are not discussed because they are not common for trout consumption.

Spinner

Body Description

Antennae: 2, short

Eyes: large

Tails: 2

Wings: 2 pair that are transparent (no mottling distinguishes them from brown drakes)

Legs: 6

After mating the males often fall spent on the ground or water with the female returning to the water to lay her eggs. When her task is completed the female falls spent to the water. The spinner falls can be very heavy where the population is large in springs.