Fifth instar caterpillar of the Calleta Silkmoth (Eupackardia calleta) from southeastern Arizona.
The large mostly black adult moths fly in July and August in the morning hours.
They are found in desert mountain thorn scrub inhabited by its larval hostplants, Ocotillo (Fouquieria splendens) and/or Mexican jumping bean (Sapium biloculare).
E. calleta ranges from southern Texas to southern Arizona in the U.S. It also occurs throughout Mexico and as far south as Honduras.