jjk
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Posts: 11 
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Post by jjk on Mar 30, 2007 20:58:52 GMT
New carnivorous plant? Or . . .  . . . the leaf of very young Nepenthes plant. What are those drosera-like tentacles for? Do they secrete fluid? Does this young form of the plant recall a Nepenthes ancestor that had tentacles on its leaves? If so, did the tentacles evolve before pitchers? Did the tentacles further evolve to become glands that produce fluid? Do the tentacles correspond to the leg extremities of whale embryos that later recede? (Mature whales have tiny remnant leg bones inside their bodies, which recall ancestors that lived on land.) I wonder if someone knowledgeable in biology or genetics can shed some light on these Nepenthes tentacles. |
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Post by rsivertsen on Mar 31, 2007 13:32:44 GMT
I've often wondered about these hairs too on the lids of Nepenthes seedlings which occur on the very first true leaf after the cotyledons; and several species retain them well after seedling stage such as N. tentaculata and N. hamatus (which I consider as an extreme for of N. tentaculata) and even N. rafflesiana. I did notice that these tentacles trap and hold a drop of water, which serves as a lens that magnifies the light into the plant’s lid, which may be helpful to the seedling if they germinate in shaded areas, or semi-buried in detritus and moss. Nepenthes seedlings have a very high rate of infant mortality, and only a very small percent of seedlings survive to adult plants.
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Post by glider14 on Mar 31, 2007 15:03:46 GMT
why do you thing N. hamata is just an extreme form of N. tentaculata... JUST LOOK AT IT!?
anyways. i have my first nepenthes seedling and i have yet to see a pitcher on it. its coming though. i dont know what the tentacles are for but i have also always wondered what they did.
Alex
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Post by rsivertsen on Mar 31, 2007 16:28:37 GMT
Well, glider, I have! Even John Turnbull, who formally defined the plant, admitted to me that "except for the peristome, it's just another N. tentaculata". Other species such as N. rafflesiana, N. maxima, and N. mirabilis all have some very different geo-forms unique to the specific locales in which they grow, some with very different peristomes, and botanically, the extreme developments of the peritome alone is questionable as a botanically significant enough feature to warrant separate species status, and may be better classified as a sub, or geotype form of N. tentaculata. Nonetheless, it does occupy a very specific, and isolated and unique area and form solitary populations; the same holds for N. ephippiata, which is very closely related to N. lowii, and may be just another geotype form, it even has the bristles under the vaulted lid, but the pitcher is not as constricted, (ventricose) as the other geo forms of N. lowii on the other mountains within the Crocker mountain chain. It could be attributable to simple genetic drift, or possibly gene pool contamination, in which some other species is involved.
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Post by Michael Catalani on Mar 31, 2007 16:51:31 GMT
why do you thing N. hamata is just an extreme form of N. tentaculata... JUST LOOK AT IT!? N. hamata is very closely related to N. tentaculata. Once you get beyond the spikes of N. hamata, the plants are very similar. Whether or not its enough of a difference to warrant species status depends on who you ask. There are certainly species of Nepenthes that are so similar that they would simply be forms or variants of each other if the same criteria for elevating Sarracenia to species status was applied to Nepenthes. Of course, discussions of species elevation can be fun and mentalling stimulating, or it can lead to an all out bar fight.... ;D |
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Clint
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Posts: 808
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Post by Clint on Mar 31, 2007 17:21:35 GMT
I'm a splitter rather than a lumper myself. I think it deserve it's own status as a species.
Then again I also think S. rosea is just another S. purpurea and S. jonesii and Sarracenia alabamensis are just forms for S. rubra.
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