While clearing away the dried sweet pea vines in preparation for mandatory brush clearance in Southern California, we encountered this lovely female Flame Skimmer, Libellula saturata, waiting to warm up in the morning chill. She was quite cooperative, not flying away until we attempted to move her from the dried vine she was resting upon. The Flame Skimmer is called the Big Red Skimmer by Charles Hogue in his wonderful book, Insects of the Los Angeles Basin.
Update: May 22, 2011
We now believe this is a female Neon Skimmer, Libellula croceipennis, based on this photo on BugGuide.