Well this could be a (nother) controversial taxon. It has been published last December in Blumea. The plant once known as "Nepenthes rafflesiana var . elongata" - an informal horticultural name for a N. rafflesiana with slender upper pitchers- has now been elevated to specied rank. It must now be refered to as Nepenthes baramensis (named after the Baram river region in Borneo).
C. Clarke, Moran J. A. , Lee C. C. (2011). Nepenthes baramensis (Nepenthaceae) - a new species from north western Borneo. Blumea 56: 229-233 (5).
(You can download the paper)
Superficially, N. baramensis is extremely closely related to N. rafflesiana so it can be bewildering to some to have them as two different species.
The paper says: "Although the visible morphological differences between them are comparatively slight, there are additional differences in ontogeny, physiology and chemistry (see Table 1, 2) that are consistent and appear to be involved in divergent N-acquisition strategies. Accordingly, we here describe the elongate form as a new species, Nepenthes baramensis sp. nov."
This will be a suprising decision to most readers I think. However all three authors are experts of the genus and their knowledge of the field is immense ; I would certainly not take their opinion lightly.
There are few morphological differences between N. baramensis and N. rafflesiana; those essentially dwell in the upper pitchers . It is clear that this treatment (ie making "rafflesiana var. elongata" a species on its own) induces that ecology should play an important role on how we classify species. Nepenthes baramensis is known for attracting bats from the species Kerivoula hardwickii that roosts in their pitchers. The plant might take benefit from it. By highlighting the importance of ecology, the authors are, in a sense, breaking new ground. A point that they highlight in the conclusion of their paper:
"The present study adds to the findings of Clarke & Moran (2011) who noted that several unique ecological relationships between highly-specialized Nepenthes species and various species of animals are facilitated by modifications to pitcher characters. However, these traits either went unnoticed, or were considered unimportant or insufficiently consistent, in previous taxonomic accounts (e.g., Danser 1928, Cheek & Jebb 2001, Clarke et al. 2010). A possible explanation for this is that important ecological interactions with animals may be facilitated by minor modifications to trap characteristics (Clarke et al. 2010, Clarke & Moran 2011), and without the support of ecological data, the taxonomic importance of these traits is easily overlooked (especially when similar traits in other species vary to greater degrees, despite having no known ecologicalfunction). Our interpretation of the status of N. baramensis is based on both ecology and plant morphology; by linking the two, we confer taxonomic value on morphological variations that might otherwise seem unimportant. [...] the use of ecological information to address taxonomic questions and hypotheses is still in its infancy with regard to Nepenthes. Although the initial outcomes of this approach are encouraging, we emphasise the need for high levels of scientific rigour in designing and conducting subsequent ecological experiments for this purpose."
This paper might be visionnary.
The paper says: "Although the visible morphological differences between them are comparatively slight, there are additional differences in ontogeny, physiology and chemistry (see Table 1, 2) that are consistent and appear to be involved in divergent N-acquisition strategies. Accordingly, we here describe the elongate form as a new species, Nepenthes baramensis sp. nov."
Photos below show N. baramensis in Brunei.
Courtesy of Vincent Bazile ;-)
This will be a suprising decision to most readers I think. However all three authors are experts of the genus and their knowledge of the field is immense ; I would certainly not take their opinion lightly.
There are few morphological differences between N. baramensis and N. rafflesiana; those essentially dwell in the upper pitchers . It is clear that this treatment (ie making "rafflesiana var. elongata" a species on its own) induces that ecology should play an important role on how we classify species. Nepenthes baramensis is known for attracting bats from the species Kerivoula hardwickii that roosts in their pitchers. The plant might take benefit from it. By highlighting the importance of ecology, the authors are, in a sense, breaking new ground. A point that they highlight in the conclusion of their paper:
"The present study adds to the findings of Clarke & Moran (2011) who noted that several unique ecological relationships between highly-specialized Nepenthes species and various species of animals are facilitated by modifications to pitcher characters. However, these traits either went unnoticed, or were considered unimportant or insufficiently consistent, in previous taxonomic accounts (e.g., Danser 1928, Cheek & Jebb 2001, Clarke et al. 2010). A possible explanation for this is that important ecological interactions with animals may be facilitated by minor modifications to trap characteristics (Clarke et al. 2010, Clarke & Moran 2011), and without the support of ecological data, the taxonomic importance of these traits is easily overlooked (especially when similar traits in other species vary to greater degrees, despite having no known ecologicalfunction). Our interpretation of the status of N. baramensis is based on both ecology and plant morphology; by linking the two, we confer taxonomic value on morphological variations that might otherwise seem unimportant. [...] the use of ecological information to address taxonomic questions and hypotheses is still in its infancy with regard to Nepenthes. Although the initial outcomes of this approach are encouraging, we emphasise the need for high levels of scientific rigour in designing and conducting subsequent ecological experiments for this purpose."
This paper might be visionnary.
Not to mention about N. robcantleyi and N. truncata, when N. baramensis is decided to be different from N. rafflesiana based on different pitcher shape and the bats sleeping inside its pitchers, why N. globosa, or N. vikingii which I prefer, is not considered a species. I am sure if associated animals to N. 'Viking' pitchers are investigated, one would find a difference from those associated with N. mirabilis pitchers.
ReplyDeleteHutcha Sriplung
Hi,
ReplyDeleteI would indeed be interested to know more about N. mirabilis var. globosa infauna. Detailed studies might provide more insight on its ecology and this could result in significant decisions. Who knows?
All the best,
François.
Thanks François.
ReplyDeleteI am not an expert in the field of Nepenthes infauna. I am a human pathologist and epidemiologist interested in Nepenthes in Songkhla province where I live. Looking around a few suburban areas in Songkhla, just very close to housing and farming lands, I cannot find a N. mirabilis var. globosa at this moment. I find some cylindrical pitchers with slightly enlarged bottom and some with rather round enlarged bottom and high hip. I also have in my nursery a few samples from Trang, northwest to Songkhla, which have Viking B pitcher form and two from Narathiwat, southeast to Songkhla on Malaysia border, which have pitchers similar to those of N. rafflesiana, which is reported to be present in that province and the nearby northern Malaysia. Some may say that they are Viking C but at my first glance, they are similar to N. rafflesiana pitchers. So I am thinking of evolution of N. mirabilis towards other Nepentheses inhabitat around the same area. To me, Viking A pitcher is close to that of N. ampullaria. My observation in Songkhla seems to suggest that there is variation of N. mirabilis pitchers in one location tending to imitate another Nepenthes which is as good in surviving as N. mirabilis in the same environment. That is why we can see such a big variation in size, shape, coloration of N. mirabilis pitchers in various areas throughout its habitat.
Sorry that this reply is fairly long. I just want to say that I feel frustated when I find some plants with pitcher shape being intermediate of N. mirabilis var. mirabilis and N. mirabilis var. globosa. What should I call them? I am sure you have ever encountered this feeling. N. Viking is fantastically nice but does it really mean something else better than N. mirabilis? I love N. mirabilis as it is.
Hutch
Hello Hutch!
ReplyDeleteconsidering globosa a species, a variety or a subspecies is just a matter of rules, this taxon could easily become a species or a form in the future, depending on what new rules will be applied. I would have described baramensis as a variety, some taxonomists might think it's not even a form, don't think there are final answers, you know about viruses and bacteria, so I'm sure you understand what I mean. But me and my Thai friend Trong (maybe you already know him) would really be interested in knowing what plants you found in Thailand, you might want to work with us if you want. My email is rafflesiana@yahoo.com, and you can know more about your local Nepenthes at www.carnivorousplants.it
Thanks a lot, Marcello. It is fun to exercise my brain with questioning and answering. I had a chance to visit Thung Khai Peninsular Botanical Garden in Trang a couple of days ago. I did not expect a lot of N. mirabilis there in the first place as I just saw an advertisement of canopy walk. Wow! There are a lot of them there. On the extreme, some have globosa pitchers and some are not different from ordinary mirabilis pitchers. But the most common plants have intermediate pitcher morphology.
DeleteIt is true that you have to follow some rules. That is fine for me. When discussion goes on, I would expect a better solution in the end.
I have not known Trong yet. I am very new in Nepenthes issue and I don't think I would change my career :P. It was just late January that I started to learn about Nepenthes. It is my pleasure to discuss with experts like François and you and also some others. Learning a new field should be started from contacting experts.