Great Spangled Fritillary (Speyeria cybele) on Swamp Milkweed (Asclepias incarnata) LaBagh Woods Chicago Cook County IL July 2016 Week #29 Jeff Skrentny IMG_2880
Fritillaries are hard! This one is much darker than ones have have seen here before. Northwestern is my best guess but it isn't listed in the Butterflies and Moths of North America website for Routt County.
custer county sw1/4; sec 15; twp 14; rq 21
NE1/4 Sec 9; Twp 14; Rq 21
NE 1/4 Sec 9; Twp 14; Rq 21
custer county nw 1/4 9-14-21
mannan ranch north of river
Custer county NW 1/4 9-14-21
mannon ranch north side of river
on thistle flower (musk)
Speyeria, commonly known as greater fritillaries, is the genus of butterflies in the family Nymphalidae commonly found in North America and Asia. Delimitation versus Argynnis is problematic, and the present genus is sometimes included therein.