General description:- Herbs or rarely woody climbers.
Leaves:- Alternate, without stipules (exstipulate), rarely opposite or stipulate.
Flowers:- Usually hermaphrodite and radially symmetrical (actinomorphic), the sepals, petals and stamens inserted on the receptacle below and free from the ovary (hypogynous). Perianth petaloid or sepaloid, arranged in whorled (verticillate). Honey-leaves (petaloid structures bearing nectaries) often present, sometimes funnel-shaped (infundibuliform). Stamens numerous, usually spirally arranged, with the anthers facing and opening outwards, away from the centre of the flower (extrorse). Carpels 1 to many, usually free and spirally arranged.
Fruit:- Usually of 1 or more follicles or a head of achenes.
RANUNCULUS
General description:- Annual or perennial herbs, sometimes aquatic.
Flowers:- Solitary or in cymose panicles. Perianth-segments (3-)5(-7). Honey-leaves (0-)5(-12), usually deciduous, petaloid, yellow or white, rarely red or purple.
Fruit:- Achenes numerous, usually with a persistent glabrous style.
Key features:-
1) Leaves simple or palmately divided.
Subgen. BATRACHIUM
General description:- Aquatic plants.
Leaves:- All with a broad lamina (laminate) or all divided into capillary segments (capillary), or of both kinds.
Flowers:- Honey-leaves white, sometimes with yellow claw.
Fruit:- Achenes transversely wrinkled (rugose).
Hybrids occur between most species in the subgenus.