Spotted Lady Beetle, Naemia seriata probably ssp litigiosa, per T. Moyer at BugGuide.com.

In the UK they're called Lady Birds or Ladybird Beetles. In the US there seems
to be an effort afoot to change the name to Lady Beetles, dropping both the "bird"
and the "bug." The Audubon insect field guide retains the classic name: Ladybug.

This one is resident in the Cardoon thistle plants on the levees of South San Francisco Bay.