Nice melon. Can't go by the yellow spot, the tendril is a much better indicator. Is it the only one on the vine? It doesn't look quite ripe to me yet, but it's getting close. I can see the ridges even though it's got dew on it, but it still looks a little too smooth and shiny. And even if it's close to being ripe, leaving it on another week won't hurt it a bit. Try and wait until the tendril dries if you can. Way more than 85 days? Are you sure? How much way more?

I scratch melonâÂÂs skin with my nails. If green skin gets under your nails, the melon is ripe;
if the nails slip on the surface, the melon is not ripe.
NOT a scientific method, but always worked well for me.

That plant went in the ground at the end of March and spent at least one month under row cover (maybe more--at least until flowering). There is a second, smaller melon but it might be on the adjacent plant--too crowded to tell.

You have to understand that "days to harvest" don't mean much here, especially with heat-loving crops. A "hot" day here is pushing into the mid-70's and we have frequent marine clouds (like today). I have to use every trick in the book to grow tomatoes, eggplants, melons, cukes, etc.

A guy likes a little challenge :-)