WEIRD larvae

So what do you suppose THIS is?! Brad, a friend in Kerrville,  messaged me this photo and asked what it was. He was hoping it wasn't the dreaded hammerhead flatworm (Bipalium kewense). The odd-looking critter, less than an inch long, was in a cord of wood that he'd bought and was splitting into smaller logs. 

 

This grub was a mystery to me! So I had to call out the Big Guns. First I went to iNaturalist and incorrectly surmised that it might be a flat-headed root-borer beetle. Which doesn't even occur in the United States! Then I emailed biologist Sam Kieschnick, aka "sambiology" on iNaturalist. He's seen nearly everything in his iNat-ing travels. "Ew, gross," he wrote back. "A bark beetle larvae! It looks like of the buprestid larvae." Well, I'll be! I've found adult bark beetles in our gardens but not any larva. At least, not yet! Now I know what to watch out for.