Yes, the others were captured this season in my pitfall traps, set around my acreage. I check the traps every afternoon (which is an opportunity to also walk the dog for about an hour. :)

I collected this crab spider last August, though. I thought I'd keep it alive and wait for it to mature. Other than a tarantula I've never had a spider take so long to molt. Maybe it was held up by some kind of internal clock? It "overwintered" as an immature in a warm vial on my desk. I kept it supplied with water and flies, though there were long periods when it wouldn't eat anything.

Food is important, and he's been eating, but all he's been getting are flies. I read a paper recently about some spiderlings that occasionally include sap from flowers in their diets (in additon to their regular prey). In lab tests, those that got it molted faster and had more energy than those that didn't. It could be that this spider supplements its diet in some way that I'm not fulfilling. If I recall correctly, I found it among some goldenrod flowers.

It might also be the time of year. Perhaps it has an internal clock that, despite being inside where its warm, is holding it back? I think hormones have something to do with initiating the molting process, but I'm not up on the details and don't know that much about it.

At any rate, it's still alive and doing okay, so if or when it molts to maturity I'll try and figure out the species and post some pictures. :)

That's interesting about the flowers.

It would seem reasonable if a male spider was stimulated to have its final molt from female hormones in the area.