Three in the Time of Five 16ths...?

I often discover after the fact that my improvised compositions have interesting mixtures of "straight" and triplet timings, but this is a new one on me:
 
In a piece that quantizes nicely to 16ths for the most part, I was hearing a triplet figure that I thought was going to turn out to be 8th triplets (360 ticks), but when I tried to quantize it to that, it was getting all fouled up. On closer examination I determined that the three notes were actually evenly spaced across the last 5 16ths of the bar (i.e. 400 ticks = 5 32nd triplets).
 
Now that I understand it, I can quantize those notes to 32nd triplets or set up a Groove Quantize reference, but now I'm curious... How would you notate that and make it clear that the triplet is over the last 5 16ths rather than 8th triplets over the last quarter? Seems like it would be hard to see the difference.
 
Any notation wizards out there have an opinion?
 
 

Thanks, Bob. I Googled several different tuplet notation references, but this one's better than most. Looks like the bottom line is you just put the bracket over the affected notes, and the notation of the preceding notes/rests in the bar should make it clear where the tuplet starts. I'll have to see if I can do it in Notion just for grins.
 
 

I think I would split the bar and put that trip figure into its own bar. Then the player can at least put it in the right place. It'd probably still take some coaching to get what you want at the performance.

Really, I think I'd notate as regular trips with an indication to play it the slightest bit early. Because math is hard :)

Thanks for the feedback, everyone. I played around with Notion a little, and below is the best I could come up with. Three dotted 8ths is 9 16ths in the time of 5. Makes some sense, and it sounds right so that makes it right in my book:
 

 
Key is Eb minor in case you're wondering. Maybe I'll throw up a little sample on my neglected Soundclick page so you can hear what all the fuss is about. 
 
 
 
 
 

What you did is essentially correct.  
 
There is no proper (traditional) way to notate an expansion, such as 3 in the space of 5.  Tuplets are only for compounding into a smaller space, so 9:5 works.  The only other option is to split the measure and change the meter, like it was suggested, to an 11/16 and a 9/16 measure.
 
I would prefer the latter approach if I were reading it.  Neither is too difficult to pull off by a good musician.  

Thanks for posting that Dave.  That has a very nice feel and mood to it.  It's begging to be developed