Annual or perennial herbs or subshrubs, parasitic or hemiparasitic. Leaves sessile, alternate, scale-like or ± linear. Flowers bisexual, solitary or in cymes, each flower subtended by 1, often
conspicuous, bract which is often adnate to the pedicel or peduncle and 2 bracteoles or (in T. atrum and T.
fastigiatum) by an involucre of 4 or more bracts. Perianth (3-4-)5-lobed, often with conspicuous external glands on the
perianth tube below the sinuses of the lobes. Stamens as many as lobes; anthers (in ours) attached to lobes by tufts of hairs. Ovary with 3 ovules. Stigma capitate. Fruit a nut, rarely
fleshy, usually 10-ribbed, crowned with the
persistent perianth. Comment: A very difficult genus to identify in the field at species level. Almost all distinguishing features are based on measurements or characteristics of minute parts, which can only be seen and compared reliably under a microscope. Worldwide: 325 species in the Old World Zimbabwe: 24 taxa. Insects associated with this genus: |
|