Corsiaceae Becc.

Herbs, perennial, achlorophyllous, holomycotrophic, rhizomatous or tuberous (Arachnitis). Stem(s) unbranched, pale red, purplish to flesh-coloured to white. Leaves alternate, simple, amplexicaul, small and often scale-like, to 50 (–70) mm long, 3–7-veined. Flowers solitary, terminal, bisexual or unisexual, epigynous. Perianth of 6 tepals in 2 whorls, zygomorphic; posterior tepal large, broad (in Corsia with a basal callus); other tepals all linear-filiform. Stamens 6, on short filaments; anthers dorsifixed, dehiscing via longitudinal slits; pollen 1-aperturate. Gynoecium syncarpous, 3-carpellate; ovary unilocular; ovules numerous; style short, free or fused; stigmas 3, papillose. Fruit (not known from Corsiopsis) reflexed, capsular, with 3 valves opening to the base (Corsia) or with 1 terminal triangular aperture (Arachnitis). Seeds numerous, very small, dust-like, winged; embryo rudimentary at time of release.