Euphorbia milii

Euphorbia milii (Crown-of-thorns or Christ Plant) is a species of Euphorbia native to Madagascar. It is a succulent climbing shrub growing to 1.8 m tall, with densely spiny stems, the straight, slender spines up to 3 cm long, which help it scramble over other plants. The leaves are obovate, up to 3.5 cm long and 1.5 cm broad. The flowers are small, subtended by a pair of conspicuous petal-like bracts, variably red, pink or white, up to 12 mm broad.
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Noun
1. somewhat climbing bushy spurge of Madagascar having long woody spiny stems with few leaves and flowers with scarlet bracts
(synonym) crown of thorns, Christ thorn, Christ plant
(hypernym) spurge
(member-holonym) Euphorbia, genus Euphorbia