or perennial, prostrate or decumbent herbs or subshrubs. Leaves simple,
opposite, entire, with short often wing-like petiole. Inflorescence an axillary
or terminal cluster or head or short spike. Flowers usually bisexual, subtended
by bracts and bracteoles. Perianth segments 5, unequal, sepaline or hyaline.
Stamens 2-5, inserted, filaments short, connate into a short cup with or
without interpassed staminodes, anther 1-celled. Ovary ovoid or orbicular,
1-celled, ovule 1, stigma capitellate (rarely bifid). Fruit an indehiscent
utricle, enclosed by the perianth. Seeds often lenticular.