|
Post by phissionkorps on Feb 19, 2008 9:15:34 GMT
First of all....so what? The peristome is one part. A defined peristome shouldn't be the single reason to elevate a species to species status. In the case of hamata, besides the peristome, the hairs on the lid branch more, everything else is the same. Not worth it to be a separate species. Btw, mirabilis echinostoma is that different. Not only is it much wider, shaped differently (both the opening and the rim), doesn't fold back, but it has spikes/spines. That's why it's named what it is.
The Australian species are species for different reasons besides just their peristomes. Tenax is much different from a "run of the mill" mirabilis, as is rowaniae. Sp. Viking isn't even about to be or in the process of being described as a species. Kurata withdrew his description, so ATM, it's not a species, and unless someone is working on getting it there, it won't be any time soon. This is a totally different topic, but besides thin leaves, sp. Viking really doesn't show much resemblance to mirabilis IMO.
I couldn't agree more. I subscribe to the fact that hamata and tentaculata are the same species, and I think the burden of proving it's a different species is on the people who think it is, not on those who think they're the same.
If you were born with perfect teeth but mine were crooked and I needed braces, are we a different species? No! I've seen some crazy raff/mirabilis forms, but 2 plants that from 20 feet away look exactly the same, and even have overlapping ranges, do not warrant being separated.
|
|
Clint
Full Member
Posts: 808
|
Post by Clint on Feb 19, 2008 14:29:06 GMT
If this were a case of selective breeding, as seen in dogs and cats, I'd have to agree with you, they are the same species; in this case it happened naturally and I've got to stick with my opinion that N. hamata, while similar, has speciated. Show me a N. rafflesiana and/ or N. mirabilis form (besides N.mirabilis var. echinostoma; you know my feelings on that: that it's not as developed as N. hamata) that has developed such an extreme feature comparable to what has developed in N. hamata, and I'll glady concede my opinion and "See the light." If N. hamata's peristome was half as developed, I'd agree with you. It's not. As far as the branching protrusions on the lid, that doesn't mean much to me. N. tentaculata is a variable species and some have relatively more branches, some have many protrusions, some have few protrusions. Isn't taxonomy fun
|
|
|
Post by rsivertsen on Feb 19, 2008 14:41:49 GMT
In my discussions with John Turnbull, after he returned from Sulawesi, he admitted that N. hamatus is really just another N. tentaculata, but felt it justified to elevate it to a seperate species status for its isolated populations with this extreme peristome. He went on to say that “the petioles, flowers and the rest of the plant are identical to any standard N. tentaculata, peristome profile, lid, and all.” There was also a rush to publish factor as Shigeo Kurata was intending to publish this species as N. dentata.
He stopped short of elevating many of the dozens of forms of N. maxima in Sulawesi to species status, and remarked that nearly every population of N. maxima in Sulawesi were significantly different from other populations, and several forms also existed within a single population; from the forms near the Lake Poso region to the wavy leaf forms, with the exception of N. infudibuliformis (N. emeyi), again acknowledging that "aside from the unusual upper pitchers, it's just another standard N. maxima."
Anyone who has grown these plants from seed has observed the variability that can arise within the seedlings, and a few “sports” and even hybrids that show up, especially in TC where the germination rate is nearly 100%. There is so much variability within some species that if someone were to select out certain traits, one could produce a very different plant within 10 generations. The problem is that they don’t flower for years, and you have to have both male and female plants.
I grew out a few hundred seedlings of many of these species, including N. fusca from Kinabalu, which, according to John Turnbull, had a very uniform population of plants with similar pitchers; yet, the seedlings ranged from lime green to dark purple pitchers, with peristomes ranging from very thin to very wide, smooth and coarse, pale in color, to striped, to solid red.
I had done some close examinations of the glands, (using 4x jewelers’ loupes to dissecting microscopes), both digestive and nectar, within the pitchers and the lid, and found these to be a far more accurate and telling characteristic for determining species than pitchers and peristome shapes; also the pollen grains, especially in ESM shots, which turned out to be fairly unique in some species. I’m surprised that more hasn’t been done in these aspects of identifying various Nepenthes species over the years. I have looked at several species that appeared visually to be very similar, but had totally different nectar and digestive glad patterns, and also their pollen grains were very different. Perhaps the argument of N. reinwardtiana et. al. could be looked at in this light. Also, the floral parts are far more botanically significant with regard to how they are situated on the racemes.
Now we have DNA sequencing, especially mitochondrial DNA which may hold clues of the evolution of the various species.
As for the N. alata complex, I have mentioned several times since the mid seventies, that the so called red forms (“N. stenophylla” and “N. burkei” from Longwood Gardens) were both highland plants, growing better in cooler temperatures and conditions, and also had fuzzy leaf margins, while the green forms of N. alata grew better in warmer lowland conditions, and had smooth leaf margins. I believe that they are separate species. Certainly, there are areas where these populations overlap, and their hybrids span the gamut of these various traits.
The populations of N. mirabilis in Cambodia and Thailand may have some genetic contamination with N. thorelli in their populations, as well as simple genetic drift.
Hybridization and gene pool contamination does occur as can be seen in N. macrophylla where the undeniable peristomes of either N. edwardsiana, or N. villosa (neither of which now occurs on the site) and the unmistakable large and vaulted lid of N. lowii are both manifest in this species.
As for the N. lowii and N. ephippeata issue, again, I believe that the latter is simply an isolated geotype of the former, with the large vaulted lid, hair spikes and all, although to a lesser extent than in N. lowii populations further north in the Crocker Mountain range, but that could still very well be attributable to genetic drift, as the N. tentaculata is also a little different in G. Rana. Perhaps some other species contaminated the gene pool, which may not even exist now.
The differences between both N. sanguinea and N. macfarlanei from the Cameron Highlands are significantly different than those same species from the Genting Highlands, yet we all agree that they are just different geotype forms of the same species.
John did mention to me that he saw several populations in the Philippines where hybrid populations of N. truncata and other species existed so extensively, that it was nearly useless to attempt to isolate any true species; similarly to areas where S. alata and S. leucophylla grow near Mobile Alabama. Generally, he said, these areas were the result of clearing and logging, which allowed heavy traffic through these populations.
I should also point out that the collectors at the Victorian (and post) times did not generally collect the botanically typical specimen of the population for taxonomic purposes, but instead collected the most ornate specimens, for their sponsors, which may have been a sport or complex hybrid, but definitely not always a true representative specimen of the population species.
Also, concider the various strains of Aldrovanda vesiculosa; from the large green Japanese strains, and the European strains, with the semi-tropical red forms in Australia and Africa, which barely even produce a dormant turion, are signifacantly smaller and different in color and form, yet they are all ONE species, Aldrovanda vesiculosa.
…. Just some food for thought. - Rich
|
|
|
Post by phissionkorps on Feb 19, 2008 22:46:38 GMT
Clint,
As I said, a different peristome is not alone reason enough to elevate to a different species. Why do you want an example from raff or mirabilis with different peristomes? Who cares? IMO, parts of pitcher morphology are helpful, but not total. We should be looking more at floral structure, and in mirabilis forms, I would also think looking at root structure would be important. Some mirabilis I've grown don't have much going on down below, while a 4" sp. Viking of mine has totally filled a pot a bit over 1 foot and 8 inches deep, with tuberous roots. Hamata and tentaculata having different peristomes is not anywhere near enough justification to classify them as different species. The argument that mirabilis echinostoma "isn't as developed" as hamata is not only unfounded but irrelevant. It could've taken much longer to arrive at echinostoma, with many more intermediate forms thatn it did to go from tentaculata to hamata.
|
|
|
Post by Sockhom on Feb 19, 2008 23:10:36 GMT
Clint, It could've taken much longer to arrive at echinostoma, with many more intermediate forms thatn it did to go from tentaculata to hamata. Hi, i think i've read a few times (don't remember where, i'll have to search) that there are in the wild many intermediate forms between what you would call a "classical" mirablis" and mirabilis var. echinostoma. I 'm not sure the same statement can be made for tentaculata and hamata but then again, i did not check in all Sulawesi spots ;D. François.
|
|
Clint
Full Member
Posts: 808
|
Post by Clint on Feb 20, 2008 0:42:29 GMT
We'll have to agree to disagree. If you think the peristome alone is not enough, that's fine. I do, however. I'm sorry, but it's just so pronounced I find it hard to ignore and cast aside.
I do think that the species from Australia and Sp. viking deserve species status. Didn't want to confuse anyone, BTW, but was just making a comparison of how similar they are (and how they are species. Well, two out of three. Not bad!)
What do you think of "Hairy" N. hamata?
|
|
|
Post by fredders on Feb 20, 2008 4:24:03 GMT
Hi guys Here's some pics taken in the wild last year of N. tentaculata's from Sabah, Borneo. There's some stunning forms out there. The pure burgendy form (leaves and pitchers) is an absolute gem. Cheers Steve N. tentaculata - Crocker Range N. tentaculata - Crocker Range N. tentaculata - Crocker Range N. tentaculata - Crocker Range N. tentaculata - Crocker Range N. tentaculata - Crocker Range N. tentaculata - Mt kinabalu, Mesilau Nature Centre N. tentaculata - Mt kinabalu, Summit trail N. tentaculata - Mt kinabalu, Summit trail N. tentaculata - Mt kinabalu, Summit trail
|
|
|
Post by phissionkorps on Feb 20, 2008 6:40:05 GMT
I think you're right. IIRC, it was on the pitcherplants forum semi-recently. Can't remember in what section though. Clint, I don't see us agreeing lol. While the peristome is something of merit, enough to warrant varietal or subspecies status, in most genera, two things that look exactly the same minus one minor change are (for the most part) not considered separate species. Think peppered moth, roses, etc. In the course of my bio training, I can't think of a single example of something that was declared a separate species because of differing by one trait, that withstood "the test of time". Sure it happens, but most are corrected in a 'relatively' short amount of time. Maybe it happens in simpler organisms, prokaryotes, etc, but I never really studied those in depth. You're focusing entirely too much on the peristome, even for a splitter. Out of say, 20 possible traits, one is different. If you look at the big picture, and especially the more important traits, like floral structure, which supersedes any type of pitcher morphology, it becomes much clearer why this should not be a separate species. Right now, nothing. I don't know enough about it to make any sort of judgement...and it doesn't seem like that many people know all too much about it either. Some propose that hairy hamata is the "original" hamata. If this was the case, it would've had to have given rise to an intermediate form that became both tentaculata and hamata, based on some sort of environmental condition. Since they overlap in elevation, the divergence was most likely caused by either contamination of the hamata genes to produce a tentaculata (by reinwardtiana? It seems to be getting around lately ), or by some sort of microclimate. That I think is plausible, but I'm not entirely sure how possible it is. The other hypothesis I suppose would be that tentaculata begat hamata, which then gave rise to hairy hamata (since "normal" hamata and tentaculata are more or less exactly the same). That would make hairy hamata a geotype of a geotype, or just a separate subspecies/varietal form. I think that's also possible, but perhaps less probable than hypothesis 1. I know nothing about the floral structure of hairy hamata, and I've never seen a female hamata flower, so I guess we're at a loss for the time being. Steve, Thanks a ton for the pics. Just for giggles, do you have any pictures of the stems/leaves and/or flowers of these plants? Regardless, the variation within and between populations is astounding , and as per normal, I'm sure there is sort of a...cline...of plants intermediate between hamata and tentaculata. Wish I could go there myself, but until then, I'll have to wait for someone to find one of those forms that makes us all go, "what is THAT!?". Unfortunately, since no one seems to want to do any sort of DNA analysis on Nepenthes that is at all informative instead of just interesting, I think an intermediate form would be too quickly declared a hybrid, when it in all certainly might not be. In fact, we might find 2 intermediate forms that look quite similar which would both be labeled as hybrids, when in fact one could be more (or totally) tentaculata, with the other being more (or totally) hamata. Sorry if that was kind of rambling
|
|
|
Post by Sockhom on Feb 20, 2008 7:46:34 GMT
|
|
|
Post by phissionkorps on Feb 20, 2008 8:27:09 GMT
Francois, Exactly, and I'm sure there are many other intermediary forms which differ in color, slightly in shape, etc. In at least one of those plants (the pic of the closeup of the lid), the hairs are unbranched. In the others, I can't tell. Again, since the ONLY differences between these two "species" is the peristome and lid hair branching (which is probably at least partially irrelevant unless taken w/ a suite (not just one other!) of traits) it's hard to say what's going on there. The plant in question has a bit more ridged and IIRC a bit wider of a peristome than a "normal" tentaculata, but I've never grown the species myself so all I have to go off of are photos. Of course, that plant could just be a sport and 100% tentaculata. Maybe, it's actually a hamata that has experienced some sort of reversion, or isn't in the same kind of microclimate as the "normal" hamatas. Do those that disagree now see why calling them different species is a bad idea? I can easily make much better cases for "alatas", raffs, mirabilises, or "maximas" to be different species.
|
|
|
Post by Dave Evans on Feb 21, 2008 8:25:54 GMT
Hi . Nice plant ddionysos. What a strange tentaculata. It almost looks like a cross with N. hamata . François. Hello François, Is it the spotting pattern? I agree, the coloration is similar. While the couple of clones of N. hamata I have are all just from one parent plant (most likely so), they do not grow like N. tentaculata. N. t. just seems to want to crawl around on the ground for a long while before it grows up into the bushes and trees. I don't see the N. h. behaving the same way. They grow straight upward and the leaves keep increasing in size, whereas N. t., they increase in length very slowly and the shapes of the two species are not very comparable. N. t. will sometimes remind very strongly of N. gracilis. This doesn't happen when I look at N. h. and I do not have to be looking at plants that even have pitchers on them... Actually, N. hispida reminds me more of N. t. than does N. h..
|
|
|
Post by Sockhom on Feb 21, 2008 8:42:47 GMT
Do those that disagree now see why calling them different species is a bad idea? I can see your point but i do not know if i will agree. There are cases of speciation being made on the basis of a major feature as you noted yourself - i'm not talking about Nepenthes only. Taxonomists have to draw the limits of the species: where does a species end? Where does the hybrid begins? We can't know if the plant shown in the link i posted is either an intermediate form or a hybrid. All we will be able to write in this post will be nothing than mere assumptions. We'll have to wait for DNA analysis and for further field researches in Sulawesi. François.
|
|
|
Post by Dave Evans on Feb 21, 2008 8:45:46 GMT
Dear Ron,
BTW, N. "viking" is not a variety of N. mirabilis, it is a species of hybridgenic origin involving N. mirabilis and N. anamensis (which also has papery leaves) or one of it's closely related and possibly unnamed species. As least, that is my bet. It could be derived in whole from N. mirabilis, but I just don't see it happening that way. Eventually, there will probably be a method of knowing for certain, but for now I'm quite happy to see it as a separate species.
|
|
|
Post by phissionkorps on Feb 21, 2008 16:20:18 GMT
Dave,
I'm just going off what Kurata has said so far. He ended up withdrawing his description because he felt it was a geotype of mirabilis. Personally, I do not agree. This is the first time I've heard about it having anything to do with anamensis though. They grow at different altitudinal ranges, which are separated by a few hundred meters. Also, sp. Viking is known only from 1-3 islands where anamensis is not present. The only species sympatric with sp. Viking IIRC are mirabilis, and possibly gracilis.
|
|
|
Post by Dave Evans on Feb 21, 2008 22:44:05 GMT
Hi Ron,
I have seen photos from the N. "viking" island showing a N. anamensis-like plant growing there, and it wasn't N. mirabilis. There is also a N. mirabilis Cana(something) from some secret location which while looking somewhat more like N. mirabilis, is really more like "viking" than it is a true N. mirabilis. I would include it into the same species concept as "viking". I feel that having tuberous roots is quite a substantial adaptation. And considering normal N. mirabilis can be found with them also just goes to show they are both products of separate evolutionary paths.
N. mirabilis var. echinostoma certainly should be kept as a variety of N. mirabilis because the change in the peristome does not appear to have been the result of natural selection, it just looks like the species is collecting mutations, and there are no other known attributes with which it could be considered as a separate species from the rest of N. mirabilis. Why even compare the situation with this variety to the issue comparing N. hamata with N. tentaculata? I don't see any connection between the two group. Like as many other CP'ers have mentioned, next to nothing is known about N. hamata because it hasn't even been studied yet and neither has the relationship between it and N. tentaculata. All I can see is they are closely related, but I don't know how. This is the specific reason there should not be any major overhaul with Nepenthes nomenclature until more research is put into understanding well established and old species like N. maxima and N. rafflesiana. We don't understand those two very well either and they are a lot more accessible, but somehow we can come to firm conclusions about N. tentaculata vs. N. hamata? It does seem funny or peculiar to me, like I mentioned at the start of the thread.
|
|