Found them in a collection of puddles in an unpaved parking lot just outside of Ballona Wetlands Ecological Reserve. The puddles act similar to a vernal pool, often present year-round except in the summer.
Hair like feature
Yellow and green
Found in abundance
1 to 2 leaves per stem
Lots of these little beetles running around today. They are very fast. The elytra are a “matte finish” rather than shiny. Photos taken with macro.