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
Pocono & Upper Delaware Hatches
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