| Annual or perennial herbs or small subshrubs. Stems often 4-angled. Leaves opposite or in false whorls. Stipular sheath present, divided into 1-many fimbriae. Flowers bisexual, usually in axillary many flowered clusters (which may run together to form a spike-like inflorescence); less often in terminal capitula. Flowers frequently intermixed with numerous ± scarious, filiform bracteoles. Calyx lobes 2-4(-8). Corolla funnel-shaped or salver-shaped; lobes (3-)4. Stamens 4, anthers usually exserted. Ovary 2-locular. Fruit usually a 2-valved capsule. Worldwide: c. 150 - 250 species, mainly America, but also widespread in the tropics and subtropics DRC: 5 taxa. | No image yet | 
| Species | Botanical divisions | Content | 
| dibrachiata Oliv. | Description, Image | |
| princeae (K.Schum.) Verdc. | Description, Image | |
| pusilla Wall. | Description, Image | |
| sphaerostigma (A. Rich.) Vatke | Description, Image | |
| subvulgata (K. Schum.) Garcia var. subvulgata | Description, Image |