I'm very pleased this is the first moor frog Rana arvalis I've seen! They are critically endangered in Bavaria where I found it. That's why I didn't even consider it to be a moor frog at first, but location and radius of ear drums, the lightly colored glands at the back, the brown speckles at the side and the snout makes it likely.
According to the Bavarian amphibian and reptile conservation organisation LARS, a small population of this species indeed appears at the location where I took the photo. Most moor frogs have a white stripe at the back, which this individual lacks. This makes me a bit unsure but I still think it's most likely Ran