Sphinx asellus, the asellus sphinx moth, is a moth of the family Sphingidae. The species was first described by Walter Rothschild and Karl Jordan in 1903. It is known from pinyon-juniper woodland and similar arid areas in the US states of Colorado, Nevada, Utah, extreme south-western Wyoming, Arizona, New Mexico and south-western Texas.
The wingspan is 80âÂÂ99 mm. There is one generation per year with adults on wing from May to July.
The larvae feed on manzanita species.