User Tag List

Informational! Informational!:  0
Likes Likes:  0
Page 1 of 3 123 LastLast
Results 1 to 8 of 20

Thread: Drosera (x)? anglica

  1. #1
    Aristoloingulamata Dexenthes's Avatar
    Join Date
    Dec 2008
    Location
    Southern Tongass Rainforest, Alaska
    Posts
    3,708
    Mentioned
    3 Post(s)
    Tagged
    0 Thread(s)

    Drosera (x)? anglica

    So after reading Cthulu's giveaway thread I was alerted to the fact that some believe D. anglica to be a hybrid between D. rotundifolia and D. linearis. I guess I am confused because whereas D. anglica can be found locally in my area in various localities, I have never seen a D. linearis before. Or maybe all the D. anglica I have seen were actually D. linearis? Somebody help me on this one. . . Are these plants actually D. linearis?





    LOOKING FOR: N. (argentii x bicalcarata) x {[(lingulata x edwardsiana) x (naga x hamata)] x [(klossii x undulatifolia) x (aristolochioides x rajah)]} Growlist: http://www.terraforums.com/forums/sh...d.php?t=124586

  2. #2
    sflynn's Avatar
    Join Date
    Jun 2014
    Location
    NW Florida
    Posts
    154
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Where did you see those plants?

  3. #3
    Aristoloingulamata Dexenthes's Avatar
    Join Date
    Dec 2008
    Location
    Southern Tongass Rainforest, Alaska
    Posts
    3,708
    Mentioned
    3 Post(s)
    Tagged
    0 Thread(s)
    These are in southern southeast Alaska.
    LOOKING FOR: N. (argentii x bicalcarata) x {[(lingulata x edwardsiana) x (naga x hamata)] x [(klossii x undulatifolia) x (aristolochioides x rajah)]} Growlist: http://www.terraforums.com/forums/sh...d.php?t=124586

  4. #4
    Hello, I must be going... Not a Number's Avatar
    Join Date
    Nov 2006
    Location
    Los Angeles, CA
    Posts
    7,506
    Mentioned
    5 Post(s)
    Tagged
    0 Thread(s)
    Drosera anglica appears to have hybrid origns between D. rotundifolia and D. linearis. The cross between these two species is sterile. However alloploidy (doubling or more of the chromosomes) can occur randomly to produce fertile seeds (and offspring).

    John Brittnacher's write up on Drosera chromosomes explains it much better than I ever will:

    http://www.carnivorousplants.org/cp/...hromosomes.php
    Drosera anglica

    Drosera anglica
    is a widespread tetraploid, 2n=40, species of known hybrid origin. Its parents are the diploid, 2n=20, Drosera rotundifolia and the diploid, 2n=20, Drosera linearis. Drosera anglica and Drosera rotundifolia are found in North America, Europe, and Asia while Drosera linearis is only found in North America in a narrow range from Montana to the Canadian Maritime provinces. Drosera rotundifolia and Drosera linearis form sterile, homoploid, 2n=20, hybrids where they grow together. As with Drosera x hybrida and triploid progenitor of Drosera tokaiensis, this homoploid hybrid will generate neo Drosera anglica at a very low rate. However it is obvious from its very extended distribution that Drosera anglica has been around for a long time. It would be interesting to study Drosera anglica across its full range to see if populations in different areas can be traced to different polyploidization events and to see the full extent that the peripheral populations have genomic differences from the populations with the neo individuals. Studies of the neo allopolyploid Tragopogon species have shown that those species had more than a dozen progenitors across numerous locations. But those populations and new species are too young to show what happens after an extended period of time as the genome(s) of the new species evolve. Drosera anglica is a good candidate for exploring genome evolution because it has populations with old and young lineages
    The notation Drosera anglica is not commonly used. Schnell made the argument that the cross "" should only be used on sterile natural hybrids, if it is fertile it should be treated more or less as a species - this pretty much goes back to old definitions of species.
    Grand Hotel... always the same. People come, people go. Nothing ever happens.

  5. #5
    Lotsa blue bluemax's Avatar
    Join Date
    Sep 2011
    Location
    Vancouver, Washington State
    Posts
    2,156
    Mentioned
    8 Post(s)
    Tagged
    0 Thread(s)
    Dexenthes - those are some sweet photos!
    - Mark

  6. #6
    Hello, I must be going... Not a Number's Avatar
    Join Date
    Nov 2006
    Location
    Los Angeles, CA
    Posts
    7,506
    Mentioned
    5 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by Dexenthes View Post
    These are in southern southeast Alaska.
    D. linearis is not known to be that far west.

    http://ontariowildflowers.com/main/species.php?id=147

    They're easy enough to identify between D. anglica by the seed:

    D. linearis: Seeds black, oblong-obovate, rhomboidal, 0.5-0.8 mm. long, densely and irregularly crateriform.
    D. anglica: Seeds black, sigmoid- fusiform, 1-1.5 mm. longitudinally striate-areolate
    Grand Hotel... always the same. People come, people go. Nothing ever happens.

  7. #7
    Moderator Joseph Clemens's Avatar
    Join Date
    Sep 2002
    Location
    Tucson, Arizona
    Posts
    2,539
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Don't forget that Drosera anglica is also known, from several different areas in the Hawaiian islands. Yet, so far as I know, no other native CP, of any kind, are found there - not even either, assumed parent species. If Drosera anglica did develop from hybrids of Drosera rotundifolia with Drosera linearis, it is natural to speculate how this species managed to arrive at its present distribution.

    Though I've visited several areas, in many parts of the world, where Drosera anglica is known to be native, the only region I've actually seen them, was at various locations in the cascade mountains of Washington state. Though I usually observed Drosera rotundifolia growing nearby, that was not always the case, either. And when they were growing near each other, they did not seem to appreciate similar micro-environments. The Drosera anglica almost exclusively chose to grow on rotten logs or small rotten branches that were floating in the water, or nearly submerged, while Drosera rotundifolia chose slightly less waterlogged locations.

    Your photos seem to show a Drosera anglica, with somewhat longer lamina than usual, but not quite as long or parallel-sided, as Drosera linearis. Very nice, though.

    - / - / - /
    It seems, that a little, expensive, genetic analysis, to compare Drosera anglica with Drosera rotundifolia and Drosera linearis, might be able to increase the confidence of this hypothesis, as Mr. Brittnacher has speculated. I, for one, would certainly appreciate seeing the results of such testing.
    Last edited by Joseph Clemens; 02-01-2015 at 01:58 PM.
    Joseph Clemens
    Tucson, Arizona, U S A

  8. #8
    Aristoloingulamata Dexenthes's Avatar
    Join Date
    Dec 2008
    Location
    Southern Tongass Rainforest, Alaska
    Posts
    3,708
    Mentioned
    3 Post(s)
    Tagged
    0 Thread(s)
    Thanks for the input guys. I guess this is a really interesting subject for me because it would seem that it could very well be possible that D. anglica is of hybrid origins, however, given the Hawaiin populations as well as all the other populations on various continents where D. linearis are not present, that it seems almost nonsensical to discuss its theoretical hybrid origin?

    I mean... one of the hypothetical parents in some cases is separated by oceans from their progeny.

    Couldn't many species of Nepenthes be referred to as hybrids in a similar respect? N. macrophylla comes to mind. It doesn't seem that far from reality to imagine that N. macrophylla is actually an ancient ingressed hybrid between N. lowii and N. edwardsiana. If so, there could be many more carnivorous plants that could get referred to by their theoretically ancient hybrid names instead of the species name that was given to them?

    Also, Joseph, I agree that D. rotundifolia and D. anglica prefer slightly different microhabitats. Although I have found the D. anglica in my area almost exclusively grow on the margins of ponds amongst grasses and reeds, whereas D. rotundifolia can be found in a wide variety of habitats, even sometimes being in woodlands.
    Last edited by Dexenthes; 02-01-2015 at 02:53 PM.
    LOOKING FOR: N. (argentii x bicalcarata) x {[(lingulata x edwardsiana) x (naga x hamata)] x [(klossii x undulatifolia) x (aristolochioides x rajah)]} Growlist: http://www.terraforums.com/forums/sh...d.php?t=124586

Page 1 of 3 123 LastLast

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •