I'm concerned about nepenthes in particular, but I guess this question applies to all of horticulture. When I write about hybrids I'm never confident that I'm obeying the rules. Here are some of the variations I've seen.
N. x ventrata
The "x" indicates that this is a hybrid. I assume that this is more proper than "N. ventrata" because that would imply that we're talking about a species. However when hybrids are named like this, should the epithet be capitalized? Why or why not? If I created this cross myself could I call my grex "N. x ventrata"?
This one is typically capitalized. It's also often in quotes. Quote suggest that we're talking about a cultivar cloned from an individual plant (I think). Are quotes preferable to no quotes? Does its status as a cultivar eliminate the need for an "x"? Or would an "x" be better?
N. maxima xx trusmadiensis
We have double "x"s here because one of the parents is itself a hybrid. I see double "x"s used very inconsistently. When exactly should we use them? And again, should "trusmadiensis" be capitalized? Does the fact that this is a natural hybrid change the rules? Lowercase hybrids do tend to be natural hybrids, but that may be a coincidence.
Scientists of TF, help me clear this one up. I don't like unintentionally propagating bad naming conventions.