Gray Drake
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.