Drosera filiformis

Life-forms

Classification System: APG IV

Superregnum: Eukaryota
Regnum: Plantae
Cladus: Angiosperms
Cladus: Eudicots
Cladus: Core eudicots
Ordo: Caryophyllales

Familia: Droseraceae
Genus: Drosera
Subgenus: D. subg. Drosera
Sectio: D. sect. Drosera
Species: Drosera filiformis
Varietas: D. f. var. filiformis – D. f. var. floridana
Name

Drosera filiformis Raf., Med. Repos., ser. 2, 5: 360 (1808).
Synonyms

Homotypic
Filicirna filiformis (Raf.) Raf., Fl. Tellur. 3: 37 (1837).
Drosera filiformis var. typica E.Reid, Bull. Torrey Bot. Club 71: 171 (1944), not validly publ.

Distribution
Native distribution areas:

Continental:Northern America
Delaware; Florida; Georgia; New Jersey; New York; North Carolina; South Carolina

References: Brummitt, R.K. 2001. TDWG – World Geographical Scheme for Recording Plant Distributions, 2nd Edition
References
Primary references

Rafinesque-Schmaltz, C.G. 1808. Essential generic and specific characters of some new genusses and species of plants, observed in the United States of America, in 1803 and 1804. The Medical Repository ser. 2, 5: 356–363. Hathitrust Open access Reference page. : 360.

Links

Govaerts, R. et al. 2019. Drosera filiformis in Kew Science Plants of the World Online. The Board of Trustees of the Royal Botanic Gardens, Kew. Published online. Accessed: 2019 May 19. Reference page.
Hassler, M. 2019. Drosera filiformis. World Plants: Synonymic Checklists of the Vascular Plants of the World In: Roskovh, Y., Abucay, L., Orrell, T., Nicolson, D., Bailly, N., Kirk, P., Bourgoin, T., DeWalt, R.E., Decock, W., De Wever, A., Nieukerken, E. van, Zarucchi, J. & Penev, L., eds. 2019. Species 2000 & ITIS Catalogue of Life. Published online. Accessed: 2019 May 19. Reference page.
International Plant Names Index. 2019. Drosera filiformis. Published online. Accessed: May 19 2019. Reference page.
Govaerts, R. et al. 2019. Drosera filiformis in Kew Science Plants of the World Online. The Board of Trustees of the Royal Botanic Gardens, Kew. Published online. Accessed: 2019 May 19. Reference page.
Tropicos.org 2019. Drosera filiformis. Missouri Botanical Garden. Published online. Accessed: 19 May 2019.
USDA, ARS, Germplasm Resources Information Network. Drosera filiformis in the Germplasm Resources Information Network (GRIN), U.S. Department of Agriculture Agricultural Research Service. Accessed: 19 May 2019.

Vernacular names
Deutsch: Fadenförmiger Sonnentau
English: Thread-leaved sundew
日本語: イトバモウセンゴケ

Drosera filiformis, commonly known as the thread-leaved sundew,[2] is a small, insectivorous, rosette-forming species of perennial herb. A species of sundew, it is unusual within its genus in that the long, erect, filiform (thread-like)[2] leaves of this plant unroll in spirals – an arrangement similar to the circinate vernation seen in ferns.
Distribution and habitat

D. filiformis occurs naturally in both Canada and the United States; its natural range extends down the eastern seaboard of North America from south western Nova Scotia[2] in the north down through New England to Florida in the south. Its disjunct distribution on the Atlantic Coast reflects the prehistoric land connection between Nova Scotia and Cape Cod, Massachusetts, which formed an ancient extension of the Atlantic Plain region that likely persisted well into the current interglacial period as an island chain.[2]: 4  D. filiformis is also found on the Gulf Coast from Florida to Louisiana, although the Gulf Coast population may represent Drosera tracyi.[2]: 3 
Cultivation

D. filiformis is frequently cultivated, with a few registered cultivars, such as D. filiformis var. filiformis (also known as D. filiformis typical), D. filiformis × 'California Sunset' (a hybrid between D. filiformis var. filiformis.) All of these cultivars are grown with similar conditions as most other Drosera species: mineral-poor soil and distilled, reverse osmosis, or collected rain water. D. filiformis require a winter dormancy for long-term survival, forming hibernacula in the winter.
Conservation

D. filiformis is a Schedule 1–listed endangered species of Canada under the Species at Risk Act.[3] It is considered range-wide to be of "least concern" according to the International Union for Conservation of Nature. Threats include development, peat mining and competition from shrubs.[1]
Infraspecific taxa

Drosera filiformis f. tracyi (Macf. ex Diels) Macf. (1914)
Drosera filiformis var. tracyi (Macf. ex Diels) Diels (1906)
Drosera filiformis var. typica Winne (1944) nom.illeg.

Part of leaf of wild Drosera filiformis var. tracyi, with captured insect
References

Smith, K. (2016). "Drosera filiformis". IUCN Red List of Threatened Species. 2016: e.T64311210A67694064. doi:10.2305/IUCN.UK.2016-1.RLTS.T64311210A67694064.en. Retrieved 9 November 2023.
B. Freedman; J. Jotham (2001). "Update COSEWIC status report on the thread-leaved sundew Drosera filiformis in Canada, in COSEWIC assessment and update status report on the thread-leaved sundew Drosera filiformis in Canada" (PDF). Ottawa: Committee on the Status of Endangered Wildlife in Canada. Retrieved 9 November 2023.
"Thread-leaved Sundew (Drosera filiformis)". Species at risk public registry. Government of Canada. 13 June 2023. Retrieved 9 November 2023.