WA Mayfly Descriptions

Map

Flyfishing Entomology

WA Mayfly Description

Taxonomic Name (Common Name)	Larva (Nymph)	Subimago (Dun) Imago (Spinner)
Siphlonuridae (Primitive Minnow Mayfly)	Streamlined; labrum w/o mid-notch; postero-lateral spines on segments 8 and 9; short antennae; mouthparts w/o comb of spines; platelike gills dorsally oriented on ab segs 1-7, and w/o dark band on outside edge; 3 tails.	2 tails and large hind wings; wing vein CuA of FWs attached to hind margin by series of veinlets; 2 tails, rarely 3.

Taxonomic Name
(Common Name)

Larva (Nymph)

Subimago (Dun)
Imago (Spinner)

Siphlonurus
(Adams; Black Drake; Westen Gray Drake; Gray Drake. )

larva (nymph)

imago (spinner) - male

imago (spinner) - female

Siphlonurus

Body streamlined; large gills with abundance of tracheation, triangular double gills on abdominal segments 1 & 2; prominent posterolateral projections on abdominal segments; 3 tails, banded at middle.

Round costal angulation of hind wing; male has pale band across eyes.

Siphlonurus autumnalis

Siphlonurus columbianus

Siphlonurus occidentalis

Siphlonurus spectabilis

State of Washington distribution is based on:
Mayflies (Ephemeroptera) of the far western United States (Part I: Washington) by M. D. Meyer & W. P. McCafferty,
and augmented by A DNA Barcode Library for North American Ephemeroptera: etc. by Webb, Jacobus, Funk, et. al.

Created: 08/16/2013 Last modified: 12/07/2014 www.FlyfishingEntomology.com