Celastrina echo cinereous

'Cinereous' Echo Blue

This smaller and darker subspecies of the echo blue may be found in the desert mountains of the eastern Mojave and up to the eastern side of the Sierras, according to the Emmels (1973). I've so far only seen it in Arizona. They have rock spiraea (Petrophytum caespitosum, a matted shrub in the Rosaceae family) as the host there.

Celastrina echo cinerea - 'Cinereous' Echo Blue
The 'cinereous' echo blue is in our eastern deserts. This female is actually from Arizona, Mt Lemmon, Santa Catalina Mtns, Pima Co. AZ, September 26, 2007.
Celastrina echo cinerea - 'Cinereous' Echo Blue
Ventral of the 'cinereous' echo blue from same hike.
Celastrina echo cinerea - 'Cinereous' Echo Blue
These were doing well most places I visited during a few days in Arizona. This one was at Montosa Canyon in the Santa Ritas, which are southeast of Tucson. October 15, 2019.
Original description of Celastrina echo cinerea - 'Cinereous' Echo Blue
This note on "var. Cinerea" by William Henry Edwards from 1883 in the journal Papilio is the first mention of this butterfly.
Illustration of Celastrina echo cinerea - 'Cinereous' Echo Blue
This illustration is in Edwards' 1884 Butterflies of North America, volume II.

©Dennis Walker