These are either Smoke tree leafhoppers (Homalodisca lacerta), glassy-winged sharpshooters (H. coagulata) or another closely related species of leafhopper. They are resting here on a dusty miller (senecio cineraria) stem. I usually see these guys solo, although I understand they occur in bunches (even swarms) on less fortunate people's plants. So I was interested to see these two together. First I noticed the nymph, which was later joined by the winged adult. Which made me wonder. Did the adult leafhopper sense (via smell probably) the nymph there and just stop by for a little leafhopper to leafhopper heart to heart? They look so tender there, you'd like to imagine they're mother and child, but we are taught to consider insects in a much colder light . . . than ourselves. Perhaps the nymphs emit some kind of signal when they are about to morph into adults, which might attract an adult of the opposite sex to stand by for an imminent and uncontested mating opportunity.
Anyway, you probably know these guys are notorious for vectoring plant disease. The bacterium xylella fastidiosa, causative agent of Pierce's disease (which is threatening California's wine industry) and oleander leaf scorch (which caused the untimely demise of miles of oleander hedge along our freeways), is transmitted by the glassy-winged sharpshooter.