Hook. f., Hook. Ic. 12:1146 (1873).
Derivation: Greek synaptos, joined together; anthos, flower; referring to the filaments which are connate to the ovary as well as the base of the corolla tube.
Synonymy: Not Applicable
Common name: None
Annual herbs with quadrangular branches rarely becoming slightly woody; leaves opposite, with hyaline stipules connate to the base of the leaf to form a sheath around the node.
Inflorescence of sessile cymules with 1 or 2, rarely up to 5 flowers per node along all branches; flowers bisexual, 4-merous; calyx persistent; corolla with a tube rarely more than 1.5 mm long, with lobes valvate, persistent; stamens with filaments attached to the base of the corolla tube and ovary; anthers without a terminal appendage; ovary half-inferior, with 2 locules each with c. 5 ovules; style short, with a broadly 2-lobed stigma, deciduous.
Fruit a capsule splitting mainly loculicidally along the upper surface.
A monotypic genus endemic to Australia.
Not yet available