Ranunculus sardosus Crantz

Ranunculus sardosus plant

Family - Ranunculaceae

Stems - To +25cm tall, multiple from base, densely pubescent (hirsute) below, less-so above, erect to decumbent, simple to branching above, herbaceous, from many fibrous roots (sometimes slightly thickened).

Ranunculus sardosus stem

Ranunculus sardosus rootsRoots.

Leaves - Basal leaves often wilted by anthesis, long-petiolate, ternate. The lobes often divided again. Cauline leaves with slightly larger blades than basal leaves but with shorter petioles, becoming sessile near apex of stems, ternate. Petioles hirsute. Lobes of blades often divided or lobed again, ultimate lobes acute, entire, pubescent to glabrous. Lateral lobes typically sessile or on very short petiolules. Terminal lobe with a noticeable petiolule. Upper most leaves reduced to bracts.

Ranunculus sardosus leavesBasal leaves.

Ranunculus sardosus cauline leavesCauline leaves.

Inflorescence - Single terminal flower. Peduncles expanding in fruit to +3.5cm long, with appressed pubescence.

Flowers - Petals 5, yellow, glabrous, obovate, 7mm long, 5mm broad, shiny above, sometimes notched at apex to obtuse or truncate. Stamens many (+/-40). Filaments to 2.5mm long. Anthers yellow, 1.5mm long, 1mm broad. Achenes smooth-sided or minutely papillose, with small curved beak to +.2mm long. Sepals yellowish, reflexed in flower, lance-ovate, to +5mm long, 3mm broad at base, pubescent to hirsute externally, scarious-margined, falling early (fugacious).

Ranunculus sardosus flower

Ranunculus sardosus calyxSepals.

Ranunculus sardosus fruitsFruits.

Flowering - May - August.

Habitat - Fields, meadows, roadsides, typically in moist soil.

Origin - Native to Europe.

Other info. - This species is still fairly uncommon in Missouri but is slowly becoming established throughout the state. It is a striking little plant but it should not be willing spread.
This and many other species of Ranunculus look very similar and a proper ID can sometimes be difficult.

Photographs taken in Van Buren, MO., 5-26-03 and off Hwy 80 near Selma, AL., 2-19-05.