Drosera capillaris

Drosera capillaris, also known as the pink sundew, is a species of carnivorous plant belonging to the family Droseraceae. It is native to the southern United States, the Greater Antilles, western and southern Mexico, Central America, and northern South America.

Description

Drosera capillaris is a perennial and herbaceous plant which forms mostly prostrate (but occasionally upright) rosettes. In more temperate regions, it grows as an annual. They can reach a diameter of at their largest. Individual leaf blades typically range from to in length. Their inflorescences can reach heights of to , forming a one sided raceme, with 1 to 6 pink, or rarely, white blooms. Flowers mature to an ovoid capsule, roughly long. They typically flower from May to August.

D.capillaris can be confused with D.intermedia (spoonleaf sundew) especially when young, as both form flat rosettes and inhabit the same habitats. However D.capillaris petioles are sparsely pilose, while D.intermedia is glabrous. Like all members of its genus, D.capillaris leaf blades are covered in glandular trichomes which excrete a sugary mucilage. Small invertebrates then become trapped by the hairs, and are subsequently digested by enzymes. The trichomes act similarly to tentacles, closing around trapped organisms further ensnaring them.

Habitat and ecology

Drosera capillaris occurs in subtropical to tropical seepage bogs, savannas, and grasslands often dominated by species of pine, including Pinus palustris (longleaf), P.elliottii (slash), or P.caribaea (Caribbean). Such habitats are subject to frequent fires (but less than their upland counterparts, which often are subject to seasonal burns). Like other species of sundew, D.capillaris is fire adapted, as elimination of competing plants facilitates proliferation of seedlings. Thick clay deposits both prevent the establishment of large trees or shrubs, and trap water. The resulting habitat are sunny but always wet. These habitats are highly acidic, sandy, and nutrient deficient, incentivizing carnivory. In North America, Dcapillaris grows concurrently with other unrelated species of carnivorous plants such as Sarracenia species (pitcher plants), Pingucula species (butterworts), and Utricularia species (bladderworts), as well as other species of Drosera. Across their entire range, other common coexisting species include orchids, Eleocharis species (spikerushes), Rhynchospora species (breaksedges), and Paspalum species.

Conservation

Drosera capillaris is listed as vulnerable in the US state of Virginia, and critically imperiled in Arkansas, Maryland, and Tennessee.