| Upper Delaware River Main Stem Emergence Table |
Common Mayflies Emergence Date* Size Body (dun) Wing (dun)
Baetis Vagans
Blue wing olive April 1st 16/18 yellow/olive gray
Paraleptophlebia
Blue dun April 10 16/18 brown/tan gray
Epeorus Plueralis
Quill Gordon April 15 14 Lt. Olive gray
Ephemerella Subvaria
Lt. & Dk. Hendrickson April 30 12/14 pink (m); tan (f) gray
E. Rotunda
Early Sulpher May 10 14 yellow/olive tinge med. gray
Stenonema Vicarium
March brown May 10 10/12 yellow/brown rib Mottled brn.
Stenonema Fuscum May 18 12/14 Lt yel/brown rib Lt. mottled
Ephemerella Invaria
Sulphur May 18 14 yellow gray
Ephemerella Dorthea
Pale evening dun May 26 18 Lt. yellow Lt. gray
Ephemera Guttulata
Green drake May 28 8/10 olive/yellow mottled/olive/gray
Ephemera Simulans
Brown drake May 28 10 Dk. brown Mottled brown
Ephemerella Cornuta
Blue wing olive June 1 14 olive/ginger gray
Ephemerella Attenuata
Blue wing olive June 7 18 olive gray
Stenonema Modestum
Delaware cahill June/Sept. 14/16 cream gray
Isonychia
Slate drake June/Sept. 12 Dk. brown/olive Dk gray
Ephemera varia*
Yellow drake July 6/8 yellow Mottled yel
Tricorythodes
Trico's # July/Oct 22 black white poly
Ephoron
White fly August 14 white white
*uncommon
#describes spinner
Baetis Vagans
Blue wing olive April 1st 16/18 yellow/olive gray
Paraleptophlebia
Blue dun April 10 16/18 brown/tan gray
Epeorus Plueralis
Quill Gordon April 15 14 Lt. Olive gray
Ephemerella Subvaria
Lt. & Dk. Hendrickson April 30 12/14 pink (m); tan (f) gray
E. Rotunda
Early Sulpher May 10 14 yellow/olive tinge med. gray
Stenonema Vicarium
March brown May 10 10/12 yellow/brown rib Mottled brn.
Stenonema Fuscum May 18 12/14 Lt yel/brown rib Lt. mottled
Ephemerella Invaria
Sulphur May 18 14 yellow gray
Ephemerella Dorthea
Pale evening dun May 26 18 Lt. yellow Lt. gray
Ephemera Guttulata
Green drake May 28 8/10 olive/yellow mottled/olive/gray
Ephemera Simulans
Brown drake May 28 10 Dk. brown Mottled brown
Ephemerella Cornuta
Blue wing olive June 1 14 olive/ginger gray
Ephemerella Attenuata
Blue wing olive June 7 18 olive gray
Stenonema Modestum
Delaware cahill June/Sept. 14/16 cream gray
Isonychia
Slate drake June/Sept. 12 Dk. brown/olive Dk gray
Ephemera varia*
Yellow drake July 6/8 yellow Mottled yel
Tricorythodes
Trico's # July/Oct 22 black white poly
Ephoron
White fly August 14 white white
*uncommon
#describes spinner
Pocono & Upper Delaware Hatches
booklet written by noted entomologist
& fly tyer Don Baylor is now available.
Order now by clicking March Brown
photo
booklet written by noted entomologist
& fly tyer Don Baylor is now available.
Order now by clicking March Brown
photo