The specific name, mearnsi, is in honor of American naturalist Edgar Alexander Mearns, who collected the first specimens.

Its dorsum is olive, brown or gray, with white or bluish spots.

Males have more pronounced throat patterns and brighter blue coloring than females.

[6] P. mearnsi is associated with boulder hillsides,[6] extending in Baja California to chaparral and pinyon-juniper woodlands.

[1] P. mearnsi is omnivorous, feeding not only on insects and spiders, but also on buds and flowers.