small dark beetle with red spots on lichens

[rjlittlefield]

A few days ago my large locust tree decided to drop another of its branches. It does this periodically. My arborists call it a "gorgeous specimen tree" and say not to worry. "They do that. It's just sudden branch drop syndrome." [ref] I try to balance following their advice against due caution, like no loitering in the drop zone. But anyway, to the point of this post...

While I was cutting up this particular branch I noticed an unusual shiny black lump moving on it. On closer inspection the lump appeared to be a small dark brown beetle with several red spots.

My first thought was lady beetle, but the size and some other details seem wrong, so now I'm thinking some sort of leaf beetle. I have uploaded the images to bugguide.net. Perhaps one of the members here recognizes it?










This last one is just for scale. The grid is 1mm x 1mm, printed with ink jet on photo paper.



All shot handheld with Canon R7, MPE-65 at various magnifications, Canon 580EX II flash with softbox head, single shots except for the last which was a 4-frame stack. Photographed indoors on a piece of the branch that had some nice lichen to go with its roughly 15 growth rings.

--Rik

[rjlittlefield]

Well, that was quick! BugGuide identifies it as Chilocorus bipustulatus, the Heather Lady Beetle. There is an article at https://en.wikipedia.org/wiki/Chilocorus_bipustulatus . It lists the size as "3–5 millimetres", so apparently this one is unusually small. BugGuide says "3.0-4.5 mm", lists the range as "native to Europe, introduced worldwide to control scale insects. In our area, established in California" and remarks that "Cannot survive cold winters, but may be encountered throughout North America during warm weather. This may account for BG sightings from NJ, MD, and even BC ‒ all near major ports."

Ironically, this species is in a group called the "Twice-stabbed Lady Beetles", despite having six spots. All the other species shown at BugGuide have only two spots -- one on each side. BugGuide explains the name bipustulatus as meaning "two-blistered".

Just now I took the first image that I uploaded to BugGuide, and fed it instead to Google image search. That nailed it immediately -- very impressive!

--Rik