The Case of Introgressed Species vs The Real Deal

[rainforest]

It has been brought to my attention that another forum has been throwing around the idea that macrophyllas (as a species) is the result of an introgressed speciation between N.macro and lowii. Let me put in my two cents and say that this is HOGWASH! You never call a species introgressed with another species a true species! If AW has any respect for the species he should call it macrophylla and in parenthesis (introgression) and that sums it up in a nutshell. The problems of having an introgressed species in the first place is because it is a TC clone. All clones of it will be the ONE (introgressed species). This is why I have been banging the concept of growing out as many seed originals from seeds as possible, make selections from clones with the best conformity and produce seed original offspring. In a tc set up, you may get a good germination population but one cannot keep them all, so the best, possibly most vigorous clones are kept. It is with great certainty that these robust individuals may possibly be hybrids (hybrid vigor) and these are what traits these producers are seeking. NOT most true to form species, just vigor, or just a random sampling.

Most likely, down the line, we will see true and pure macrophyllas. If that day comes, what do we call all the bogus macrophyllas that are around with a best as can be macrophylla name? And when crossing two marophyllas, then this will be hybridization at best!

If it is common knowledge that a species is of hybrid origin, then by all means state that fact! I hate it when people just give up because there isn't any around and start calling something that's not a species, a species. Introgressed or not, it is not the same!


M

[dvg]

I think part of the problem is that we are currently seeing less than one degree of the whole pie, in other words a very thin piece of this whole picture.

It seems that Nepenthes species interbreed with each other quite readily. Over longer periods of time than we have been observing them, they evolve. So what would once be considered a solid species, can in time morph into something quite different from one measured starting point, and also supply it's genetic material for new hybrid crosses, that we down the line will call species, once we happen to 'discover' them.

Some people are speculating that N. macrophylla might actually be a hybrid cross between N. edwardsiana and N. lowii. If this is the case, one should expect some variation.

Maybe it is difficult to pin down exactly what a true macrophylla actually is. There seems to be quite a bit of variation among this species in situ and this topic has been raised and discussed many times before. I really get the feeling that growers want to see the extremely defined teeth on this plant's peristome, in order for it to be considered a true species. And since 'species designation' seems to be an artificial construct at best, with us making that designation, we probably are guilty of misdiagnosing 'true species' at times.

The point I am trying to make is that it might not be as simple to define something as a species while it is in the process of changing, and probably always has been, than we might think it is. This might be a feature length movie and we are only looking at one or two frames at best, and already trying to guess the outcome of this story.

dvg

[rainforest]

The original description of N. macrophylla was not based on a single unique specimen. It was described with some details and specifics. Now we are breaking these rules of nomenclature because we assume that these are really hybrids? WE know that N. macrophylla is not N. Trusmadiensis, neither is it N. edwardsiana. Each has its own features that we know that it differentiates from one another. If that were true, we'd also have N. trusmadiensis as a true described species too. But we don't.
N. macrophylla exists.
The same holds true for N. clipeata, we only see N. clip hybrids because the gene pool is so small. The only way we can get a pure clipeata is if we hand pollinate N. clipeata between two clipeata plants. The same must be done with N. macrophylla. WE must cross true macrophyllas together (as with all species) to get true species seed/plants/adults. TC individual clones just doesn't cut it.
M

[dvg]

There still seems to be some controversy over what is and what is not the true N. macrophylla, especially with regards to some of the clones available in cultivation.

I've noticed that if a clone doesn't have a uniform spear- shaped opening to the peristome, but instead has some pleating or creases, these macrophyllas are considered suspect.

And if the teeth are slightly muted, without the extreme defined high teeth and the deep valleys between them, then this characteristic is also considered as suspect and that pitchers with these muted qualities may also indicate a hybrid is likely.

Some now suggest to count the number of teeth on the mature peristome, because too many teeth is considered a hybrid trait. So how many teeth are allowed on the peristome to be considered to be within the acceptable range of being a true macrophylla?

And even with the pleated peristome and the muted teeth, there are some that still believe that this these phenotypical traits are still within the range of being a true N. macrophylla. So the controversy continues on.

Maybe the species needs to either be more narrowly defined, or conversely more broadly defined so that there is more consensus on what traits constitute a true N. macrophylla.

And even though we might think that macrophylla exists and is a true species, how can we be certain that it is not a result of a hybrid parentage, from somewhere in the past? And if it was a result of a hybrid cross, then there would still be some variation to be expected in this 'species'.
dvg

[Dave Evans]

Because, N. lowii, N. rajah, N. ephippiata , N. edwardsiana, N. villosa, N. macrophylla have been evolving independently; becoming less similar from their shared ancestors over time. They do not continue breeding together while still evolving apart!

There is no evidence N. macrophylla, N. murudensis, N. petiolata, N. hurrelliana, N. vogelii or N. platychila are hybrids. There is plenty of evidence to support normal speciation via radiation of ancestor species. Seems only a tiny handful of highland species might be hybrids, while it is the lowlander species that do show evidence of hybridization in their DNA. The lowlanders are less segregated into specific areas, whereas highland species are more specific to particular mountains or groups of mountains.

I'm really not sure why, or what makes people continue to label some species as hybrids without any reason for it... And for the most part it is the highland species which get these 'hybrid' labels; when it is the lowland species that are of hybrid origin--yet are no longer hybrids.

Apparently, N. lowii, N. macrophylla and N. x trusmadiensis have been crossing a lot lately--or seed collectors have been having lousy luck and have been unwittingly collecting hybrid seed.

[rainforest]

Species tend to hybridize when their balance has been disturbed. This holds true for macrophylla which has habitat which is disturbed and many other nearby species encroaching into macrophylla territory. Now it is so difficult to find macrophylla seed, any seed pod on a macrophylla will do.
N. Alisaputrana was the result of crossing out to burbidgeae from scarce rajah (at the time) in the way that Trusmadiensis has been produced by crossing out macros from lowii's. But N. rajah has bounced back with more and more rajahs growing and allowing pure seed making in the process. It is now very rare to find N. Alisaputrana and very few new Aisaputrana can be found.

Until the day that macros can return like N. rajah, we probably won't see any pure macros until then.

M