This is the other Psyllobora in the PNW. If you compare this to Psyllobora vigintimaculata you will see the differences in the pattern, chief among them being that the lateral spot in P. borealis is much smaller and is not joined to the median spots. This beetle was also a little bigger (3.2mm). .7mm is definitely noticeable when they are this small!
They are also powdery mildew obligates. The range of the Western Psyllobra is restricted to the west, and is found throughout our region. As far as is known they have the same life cycle as the 20-spotted Lady Beetles.
It was pretty exciting to find this bug just a week later. Being that it was perceptibly bigger, the pattern was more obvious and I was fairly certain of what I had immediately. Both Psyllobora just a week and a few hundred yards apart. That’s some good bugging!
https://bugguide.net/node/view/110588
Size- 2.5-3.2mm
Habitat- Damp areas with powdery mildew
Range- Region wide
Eats- powdery mildew obligate
Flight Season- Adults can be found year around in our region, though they may not be active during the coldest months
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