Southern Dogface
Colias (Zerene) cesonia
The sulphurs can look very similar
in their ventral aspects. So this one is not distinct except
for its falcate forewing. It is only when you get a glimpse of
its dorsal
side that it appears to be more positively a Southern
Dogface.
"The wings are sharply pointed,
even slightly falcate, not rounded as are those of the other
sulphurs."
This
is the Dogface on the Butterflies of North America webpage.
Picture taken with a Nikon D90, using
a Nikon 300mm, f/4.5 lens.
October 9, 2016.