A Red, Squiggly, Fairly Blotchy “What am I?” Quiz

Nikon D4 + Voigtländer 125mm f/2.5 — 1/250 sec, f/2.5, ISO 4500 —
map & image data — nearby photos

What am I?

It's been a couple of months since my last “What am I?” quiz, so here's one.
What is the photo of?

As usual, I'll keep guesses private until I post the answer in a day or three...