Ranunculus L. >
Petals yellow. Leaves sometimes divided into linear segments but then 1 mm wide or more and arranged in one plane only Ranunculus
Leaves lobed or deeply dissected
Sepals not reflexed, 5 or more
Achenes covered with spiny tubercles
Nearly glabrous annuals with stout stems, erect diffuse or prostrate and creeping and rooting at the nodes. Leaves 1–5 cm long; petioles with a sheathing base. Flowers 10–15 mm diam. (rarely 20 mm). Sepals reflexed. Petals yellow, slightly longer than the sepals. Achenes up to 5 mm long, with spiny tubercles on the sides and a stout recurved beak. Widespread. Weed in moist places and lawns. Introd. from the Mediterranean. Fl. spring. Sharp Buttercup or Rough-seeded Buttercup. Ranunculus muricatus