Subject: A mystery white, and a checkerspot?
Location: Larimer county, CO, 8100′
October 10, 2014 8:46 am
A couple butterflies I hope you can help with. Both taken same location. Larimer county, Colorado foothills, 8100 feet elevation. October 8, 2014. Warm day, but well past 1st frost. The first is a white, of sorts. Markings don’t strike me as cabbage white, and doesn’t seem dark enough for pine white (especially underside). Whites (or white morph sulphurs) are troublesome for me. …
Signature: Matt in CO
We are going to split your request into two distinct postings as they need to be categorized into different butterfly families. We believe the White is a male Checkered White, Pontia protodice, and according to BugGuide: “Sexually dimorphic. Males are nearly all white, with some dark spots and dashes on the dorsal side of FW. Females are have considerably more dark markings on the dorsal side of FW.” BugGuide also notes: “Rather irregular in distribution in eastern North America, not seen every year in many localities, such as Piedmont region of North Carolina. Can be extremely abundant, sometimes in the Southwest and Great Plains with thousands of individuals swarming flowers and puddles, and even coming to lights at night. Can seem to disappear for a year or three during extreme drought, only to explode in numbers when rains come.” In Butterflies Through Binoculars The West, Jeffrey Glassberg writes: “Most frequently encountered in the lowlands, but can be found on high peaks.”