I can't search on the word "key" here, so I'm not sure if there is a thread on this. I don't understand how to read the eFlora keys. Is there an explanation somewhere of how they work? For instance, here is what I want to understand: From Opuntia in Flora of North America @ efloras.org: 5 (4) Areoles in distal 1/3 of stem segment bearing 0(-1) spines, spines absent from basal 95-100% of stem segment; fruits spineless 30 Opuntia aurea + Areoles in distal 1/3 of stem segment bearing 1-4 spines (spines absent from basal 50-80% of stem segment); fruits spiny (6) On the left, I think I understand that this is item 5 and it came from 4. And the + is another option. It's on the right I don't understand. What is the difference between 30 and (6) with the brackets? If the text on the first item is satisfied, then it's Opuntia aurea, and we're done, is that right? So what's the 30? I assume the (6) is: go to 6.