I haven't seen one of these for a long time, and it's odd there would be only one, but there it was on the broccoli leaf when I went to pick vegetables this morning. The broccoli that we'd almost given up on after the birds whacked away at the seedlings many many weeks ago. After all that damage, this is probably the best crop we've ever had.
When I started to look at the larva images, I noticed a lot of those transparent skeletons scattered over the leaves. Maybe an earlier instar of the ladybug? I went back later but everything was gone.
I guess I should say that this little creature is about the size of my fingernail.