Ranunculus rionii Lagger in Flora (Regensb.) 31: 49. 1848.

Herbs, short-lived annuals, aquatic. Leaves all submerged, capillary, 3 - 4 cm long; laminate leaves absent. Flowers white, ca 1 cm wide; pedicels much longer than leaves. Petals less than 5 mm long; nectar-pits lunate. Receptacle hairy, elongated in fruit. Achenes 60 - 90, subglobose, up to 1 mm long, glabrous or nearly so.

Fl. & Fr. April - Aug.

Distrib. India: W. Himalayas. Jammu & Kashmir.

Pakistan, C. & S. Europe and S.E. Russia.