NPSpecies

P. tharos looks similar to P. batesii, and it seems that lab work might be needed to separate the two. P. tharos is a North Rim resident, though John S. Garth collected a voucher specimen at the “Aspen Glen”, which is the only surviving stand of Quaking Aspen Populus tremuloides on Grand Canyon’s South Rim, 10 June 1942. Larval host are Asters (Asteraceae). Adults fly in spring, summer, and fall.