Install worked great... but which USB option is my drive in boot menu?

Everything went fine from buing my ISO to installing Ubuntu via the tutorials online to my USB3.0, 64GB flash drive. But when I boot, and go into boot drive selection I get
- USB-ZIP
- USB-FDD
- USB-HDD
- USB-another one here that I don't remember. I want to say "USB-CD"

I've tried them all with the flash drive plugged into motherboard USB ports (I mean not add-on PCIs or faceplate readers) and it's like the drive isn't there? It definitely installed correctly and has the drive structure it should have.

Any thoughts? Thank you!!