From what I can see does look like a red spider mite.
That’s not what did the damage to the one leaf though.
I’ve had a rouge bug come in the night and take a chunk out of a leaf here and there and haven’t really worried about that as I take of more than that sucker can eat in a lifetime lol.
Now about the red spider mite…could be a plant sucker mite (vegetarian) or could be a meat eater predator mite. The predators eat the plant sucking mites. But if there isn’t food for them they may turn to the plant to survive.
I would look closer at all the plants leaves top and bottom and the soil and container for movement of mites.
There are many ways to treat for them.
Below is a link to a thread I started as I am current dealing with spider mites eating my plants.
Rather than post any details here take a look at the thread and read up for some options if you find more than that one…and you usually will if they are plant eaters.
You may have brought it in from being outside and then going into your grow area without removing your shoes or shaking off etc.
Some will strip down to their skivies and or shower etc before going into grow area as a precaution.
Good luck and let us know if you have any other questions…
And great catch @elheffe702