Apparently I should have held onto this one. Oops.
Once again a huge number, I'm sure I personally saw 30 or more. Had to be careful not to step on them! Size range maybe 8-20 mm.
Juvenile? About 1" long.
In the additional photos it is the larger, lighter one.
Body was darker than the usual sort, with a greenish cast. Tail had a lot of yellow. In the additional photos it is the smaller, darker one.
Under redwoods next to fallen log.