Herbs, monoecious or dioecious, fleshy, parasitic on roots or rhizomes of various hosts. Rhizome usually branched, usually with scales or warts and/or lenticels. Flowering shoots endogenously arising from rhizome; scapes with or without leaves, unbranched. Leaves scaly, opposite or alternate and distichous or spiraled, sometimes whorled, rarely contorted or clustered, without stomata. Inflorescences unisexual or androgynous, terminal, spadix or spadixlike structure covered with minute branches; branches frequently subtended by variously modified bract. Flowers unisexual, pedicellate or sessile. Male flowers: larger than female flowers, 3(or 4 or more)-merous. Perianth apically lobed or dentate, sometimes absent; lobes valvate. Stamens 1 or 2 when perianth absent or usually as numerous as and opposite to perianth lobes when perianth present; filaments free or connate into a synandrium; anthers free or connate, 2-loculed or more, dehiscent by slits. Female flowers: congested on branches or basally on spadicles and/or shoot axis. Perianth absent or reduced and 2- to irregularly lobed, adnate to ovary. Ovary inferior. styles 1 or 2; stigmas slightly capitellate. Fruit a 1-seeded achene.
Stamens 1–2 in the achlamydeous flowers, in those with a perianth often equal in number to, and opposite the lobes; filaments free or connate; anthers 2–4-celled or with many cells, free or connate, opening by pores or slits
Flowers unisexual, very rarely hermaphrodite, densely crowded into unisexual or androgynous inflorescences; male flowers without or with a valvate 3–8-lobed perianth
Fleshy herbs parasitic on roots, annual or perennial, destitute of chlorophyll and stomata