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yucca beetle - Mycterus quadricollis - male - female

yucca beetle - Mycterus quadricollis - Male Female
Pinyon Flats Campground off Hwy 74 in the San Jacinto / Santa Rosa Mtns, Riverside County, California, USA
May 8, 2008
Size: 5 & 6 mm
I first thought these were chrysomelids but the antennae look wrong. This is a male and female -- the male has fancier antennae and is a little smaller than the female. There were a lot of these feeding on yucca flowers. They were especially active at night but they were not hard to find in the daytime also.

Mycterus quadricollis Horn -- det. D.A. Pollock
Moved from Mycterus.

I am pretty sure these are Mycterus. See here or here or here for Harvard types. I can't make out tarsal count on metathoracic legs. Will be 4 if a mycterid. Matches drawing of Mycterus in American Beetles quite nicely.

Nice find and great pics!

I think you're right Jeff -- thanks! I spent a long while trying to figure out what these are ... after I realized they're not chrysomelids. The tarsal count on the metathoracic legs is 4 -- I added this photo:

I don't think this is the same Mycterus species (concolor) as the one depicted in American Beetles ... the second Harvard type you link to looks closest. SBMNH lists 4 Mycterus in California. Specimens of one of them were collected within half a mile of where I was. I'll see what I can find out from Essig museum specimens when I get a chance.