Windy Hill OSP, San Mateo County, California, USA April 3, 2015 Size: ~15mm
On quite a lot of the Ranunculus californicus these flies clung motionless to the stems just below the flowers. Some had distended abdomens like this one, and some looked dessicated. It was about an hour before sunset, and cold. We weren't sure if they were gravid or had some kind of parasite.
There were flies also on the next night.
Contributed by Debbi Brusco on 11 April, 2015 - 3:15am Last updated 23 October, 2015 - 9:12am
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