Herb, with widely spreading
prostrate annual stems. Leaves variable. Flowers solitary in leaf
axils, borne on long erect pedicels. Corolla obliquely
campanulate; limb slightly 2-lipped. Stamens 4. Ovary 2-locular.
Fruit disk-like with 2 erect conical spines from the central
raised portion.
Derivation of name: di - two; keras - horn; karyon - nut (Gr), referring to the two-thorned fruits.