OK, still no oranges – promise, hand on heart we’ll get there shortly.
Now, in my continuing quest for education I decided to look up ‘Ferns’ on the infernal wide web and I’m very glad I did – just look what I found out: One problem with fern classification is the problem of cryptic species. A cryptic species is a species that is morphologically similar to another species, but differs genetically in ways that prevent fertile interbreeding. A good example of this is the currently designated species Asplenium trichomanes, the maidenhair spleenwort. This is actually a species complex that includes distinct diploid and tetraploid races. There are minor but unclear morphological differences between the two groups, which prefer distinctly differing habitats. In many cases such as this, the species complexes have been separated into separate species, thus raising the number of overall fern species. Possibly many more cryptic species are yet to be discovered and designated.
The maidenhair spleenwort? Eh?