Bogs and Acidic Peatlands of Southern New England by Marsha C. Salett
Drosera filiformis Raf.
DROSERACEAE (Sundew Family)
EtymologyDrosera means dewy, from the Greek droseros, in reference to the glistening gland-tipped hairs on the leaves; flilformis means with thread-like leaves, from the Latin: filum = thread + formis = in the form of.
Synonyms (Common Name)Dew-thread, Thread-dew
DescriptionAlong with pitcher plants (Sarracenia purpurea) and bladderworts (Utricularia spp.), sundews are insectivorous plants of nutrient-poor bogs and peatlands that obtain nitrogen and other nutrients by trapping and digesting insects and other small organisms. More rare than other New England sundews, thread-leaved sundew is found only on sandy peats of the coastal plain. The long, thread-like leaves of this tiny, perennial herb set it apart from other sundew species, but it captures its prey in the same manner. Insects are attracted to a sticky substance on the sundew's leaves and become trapped. As an insect struggles to escape, its movements trigger a rapid cell-growth mechanism in the hairs and leaves of the sundew that causes the leaves to fold around the prey. The sundew then produces an anesthetic that numbs the insect and digestive enzymes that dissolve it. Nutrients are absorbed into the plant tissues by the hairs; only the prey's exoskeleton remains.
Wetland indicator statusOBL
Plant Height6-16 inches
LeavesLong, narrow, string-like, 6-12" long; blade not separate from the stalk; red, glandular hairs topped with drops of sticky dew; form a basal rosette.
Flower/InflorescenceSmall (3/8-3/4"), lavender, 5 petals; in one-sided racemes along a leafless, curved stalk 8-20" tall; open at the bottom a few at a time.
Flowering PeriodJuly-August
FruitCapsule, small (3/16 --5/16") elliptical, 3-valved, many black seeds.
HabitatSandy pond margins; damp sand and peat along the coastal plain.
RangeMassachusetts to Delaware; South Carolina to Florida and Louisiana; along the coast.
(c) 1998-2006 Marsha C. Salett