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Well as we all know all of the upright (not including the climbing D. macrantha) Drosera in South East Australia have been reduced to the same species, D. peltata. Howerver these "forms" grow side by side, look different, are geneticly isolated from each other, have different looking flower structures and here are the seed!

seeds.JPG


From left to right with 4 seeds of each, D. auriculata, D. sp. "foliosa", D. peltata.

Oops here I go again I mean D. peltata, D. peltata and D. peltata...

Sorry about the sarcasm couldn't help myself
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I took the pics by holding my camera against the eye peice of my disecting microscope. It worked supprisingly well. Once again Tamlin was right, it was well worth inspecting the seeds...

George
 
Here is a nice pic of a D. sp. "foliosa" I took a few weeks ago at a VCPS field trip.

foliosacran3.JPG


I do like these plants. They are always an intense green, even in full sun.

George
 
Excellent work George!!! I hope you will be able to take many more seed photos. I will be putting together a good selection for you to work with, I simply MUST get a dissecting microscope if you can get results like these!!!

BAsed on the scale in these photos the Drosera lamina look to be huge. What a beauty! Thanks again for sharing the *fruits* of your labor.
 
George,

To answer your question on what makes a species in this case:

1) Seeds more or less narrow-ellipsoid, occasionally oblong-cylindrical, 0.3-0.5 mm long; basal unbranched part of style 0.1-0.3
mm long; sepals 2-4mm long, hairy or glabarous; petals 5-6 mm long: a subsp. D. peltata

2) Seeds narrow-linear to oblong-cylindrical (0.5-) 1 mm long. Glabarous; petals 7-8 mm long: a subsp. D. auriculata

If the presence or absence of indumentum on the sepals is used as a criterion for separating D. auriculata from D. peltata, then it is unjustified to maintain these two as separate species while regarding other species formerly recognized by minor characters. e.g. D. lunata, as synonyms of D. peltata. If we regard the shape of the seed as a fundamental feature to distinguish these two species, then some specimens which are classified as belonging to D. peltata (because they have hairy sepals), would have to be regarded as D. auriculata, even though their other features do not support such a separation. The presence or absence of indumentum on the sepals is of secondary importance and the variation in shape of the seeds is such that there is too much overlap of character to support maintenence at species level.

The best solution, based on an assessment of the wide range of variation within the population (e.g. as found in Australia and New Guinea) and accounting for the existence of distinctive sympatric populations (e.g. as found in Australia in parts of the geographical range, is to recognize two infraspecific taxa based on a combination of characters. The morphological differences observed between these two taxa represents infraspecific variation. Accordingly D. auriculata is reduced to a subspecies of D. peltata.

Other distinguishing criteria are in D. auriculata the lamina of the basal leaves are flabellate and folded, infloresence 1-2 flowered, erect stem flexuous.

Hope this helps!
 
Ok, acording to my 10th grade biology "the defination of a species is any group of plants\animals\micro organisms that when hybridized produce fertile offspring"
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Pond Boy, as my 1st year chemistry lecturer said "Forget everything you were taught at high-school, it's all wrong"... although that is a good place to start segrigating species
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[b said:
Quote[/b] ]"If we regard the shape of the seed as a fundamental feature to distinguish these two species, then some specimens which are classified as belonging to D. peltata (because they have hairy sepals), would have to be regarded as D. auriculata, even though their other features do not support such a separation."

This is very interesting as all the plants I have seen are consistent in seed shape and sepal apearence. Long seeds = smooth sepals, oval seeds = hairy sepals. So from what I have observed these two criteria are supportive of each other. I have only been able to sample a (relativly) small range within a few hundred km of Melbourne. Although this matches up with work being done in other parts of Australia. There are a few odities out there which do have some intermediate characteristics (D. gracilis), but these hold true throughout thier range and as such these populations are beleived by some to be distinct species that simply to have some characteristics of two other species.  

[b said:
Quote[/b] ]"Hope this helps!"

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 Thanks a heap, where did you get this information from?

My brain hurts...

George
 
The information was taken from:

The Drosera peltata - Drosera Auriculata Complex, Barry J. Conn
J. Adelaide. Bot. Garden 3(1): 91-100 (1981)

and also from Dr. Jan Schlauer's revised key for Drosera published in the 1995 International CP Newsletter.

I'll send you a copy of the whole article. I find it interesting in that it describes the problems associated with defining the leucotype based on several confused issues in herborized specimens.

This was the instrument responsible for changing the rank of D. auriculata to a ssp. of peltata, but it surely won't be the last word on the subject as this is the topic of Robert Gibson's PhD dissertation, and Robert is being most inclusive in his treatment after reviewing all the Australoasian material. I really am looking forward to seeing it, and he's getting there with it! It won't be much longer :) I will of course be sure you have it in hand as soon as it is published.
 
  • #10
Tamlin, I'd love a copy of the article. I emailed Jan yesterday, I dug his email up via the ICPS website I hope I got the right email address.

I collected some seeds from another location which has all 3 types. The seeds look the same as from this other location. I will try to get some pics tomorow to post.

I will have to send you an email, I have been really busy lately with work, and trying to keep ontop of all these plants now spring is here!!
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Robert is a very knowlegable person and I can't wait for his paper to come out.

George
 
  • #11
Also the lamna on the "foliosa" are quite big for the size of the plant. The plant in the photo would be lucky to be 6 inches tall and that was a big plant. If that was an auriculata it would be a midget, and the largest lamna I have seen are on some "foliosa"! They are a top plant.

To get seed into the US do you only need a phyto?

George
 
  • #12
George,

It varies from species to species. I dug long and hard, and in the end I was told one must specify which species are involved, then, after the usual beaucratic delays, I would be informed as to what is required. A phyto for sure, and possibly additional permits from the Federal Food and Drug Admin. and also possibly Fish and Wildlife.

I know some folk that help me from time to time with permits and connections, so message me if I can be of any assistance.

Take your time with the email: I am so busy right now I have hardly time to sleep, and email replys right now are largely brief sentences. Have fun with your plants, and good growing mate!

Errr, better resend your snail mail address to me at least though, and I will send the article off to you!
 
  • #13
I went for bit of a wander the other day and collected a few seeds. I collected from two areas where there were D. auriculata, D. peltata and D. sp. "foliosa" growing near each other. Here are the pics...

Seeds_Lystrfield_far_side.jpg


Seeds_Lystrfield_bellow_wall.jpg


The seed apearence seems quite consistent with other locations I have seen. In the first pic the sp. "foliosa" seeds came from a very robust plant that had quite large seeds, and in the second pic the foliosa seed donors were quite small (younger?) and less advanced.

George
 
  • #15
Done!

I have found freewebs can be a pain sometimes. I don't think they like linking pic to the site. They work a lot better if you paste the URL into your address bar
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I need a new host...

George
 
  • #16
It works now! Nice photos! Robert Gibson certainly disagress with the reassigning of D. bicolor's rank. I will ask him what he thinks of the issue with D. foliosa when I next write, you have spiked my curiosity!
 
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