Eric
Carnivore
This is D.filiformis from NS. I received just a dozen seeds two years ago. The letter with the seed travelled 4 times between 3 different continents without getting lost or smashed. Germination was good and I grew 6 clones to maturity.
Here some more close-ups of the flower (before and after anthesis):
The hibernacula in fall and some leaf close-ups:
D.filiformis is native to a small area in Nova Scotia and is restricted to a few bogs. It was found there for the first time in 1977. Extensive search came up with a total of five populations nearbye, but only three harbour a significant number of plants. There were proposals for peat mining in that area, which would have wiped out one population and threaten this species' existence in Canada. Luckily this plan was stopped in 1991.
Southern NS is the only area where it is native in Canada and the northernmost natural occurance. Some plants were transplanted about 200km farther north-east to a coastal bog near Halifax where they grew well for many years and probably still do. D.filiformis has a wide latitude distribution (30°N - 44°N), but it is not continuous, but patchy: The natural populations in NS are separated by more than 400km from the next populations in Massachusetts. The populations on Long Island (NY) are more than 100km from the few sites in New England. The next gap is about 250km to New Jersey which is the stronghold of D.filiformis. Skipping a few naturalised populations it is about 700km to the few populations in North Carolina. The small area in Florida, where D.filiformis is found, is more than 800km from there.
There may have been more linking occurances in between that were inundated following the sea level rise after the last ice age. But the present populations are now geographicaly quite isolated. Migrating birds may connect some of those populations, but long distance dispersal is not a common thing. Probably it does not influence existing populations a lot. A peat core analysis in southern NS found fossile D.filiformis seed down to more than 2m deep in one bog. Radiocarbon dating proofed that this species grows here for more than 4000 years, so it is no recent introduction by birds or men.
Are D.filiformis from NS more cold resistent? Not necessarily. Southern NS has a relatively moderate (hyperoceanic) climate due to the proximity of the ocean currents. The pine barrens in NJ have the same hardiness zone 6b. That's why the flora is similar too. Southern NS is famous to harbour some other species typical of the Atlantic Coastal Plain, some of which have a similar, wide distribution range with disjunct populations.
Do D.filiformis from different places look different? Here some leaves from different geographic locations side by side:
The plants in Florida, once called "Florida Red", now called var. floridana (Rice 2017), are definitly different: e.g. they are smaller, have much redder leaves, the petiole (lower part of the leaf without tentacles) is much shorter, the leaf width is more narrow, they have thinner scapes, the seed capsules are rounder, and the seed shorter. They do form hibernacula, even though not as tight as the more northern forms, but they are still a lot more winter hardy than D.tracyi.
As a side-note: D.tracyi was described as a species by J.M.Macfarlane in 1914, but regarded as a variety of D.filiformis in the past, because it also has thread leaves. More recently the two are seen as separate species again (Rice 2011). It grows along the Gulf coastal plain from MS to GA.
D.filiformis var.floridana grows in a very small area in FL within the overall range of D.tracyi. Natural crosses between the two are known (D.x californica var.arenaria), but the red filiformis grow in a different habitat (white sand lake shores) and remain distinct from D.tracyi. The man made crosses between tracyi and filiformis (likely from NJ) like 'California Sunset' are common in cultivation, sometimes passed on as plain D.filiformis.
The D.filiformis from all the locations along the Atlantic coastal plain are considered as var.filiformis, because the differences are much smaller. Those in NC are taller and slightly greener, the seed slightly more elongated. There are two forms with unusual flower colour in NJ, but otherwise all forms from NJ to NS look a lot alike. There is a nice overview in CPN (Brittnacher 2018). Finally some leaf sections from the middle of the leaf. Beside the leaf colour and size it has been suggested to use the ratio tentacle length / leaf width to distiguish filiformis (2.6-4.8) from tracyi (0.9-2.3).
