Dear FM,

 Can you say this plant could seen where ? You have to clear that this plant fond at which area?

Your identification is correct. In India it is in cultivation and also found in wild,  an escape from cultivation. 

This species has long been in cultivation and plants have been introduced to many countries where they have escaped and become naturalized. As a result it is impossible to distinguish the true native range from the introduced range. The species is thought most likely to have originated from Panama in Central America, but this is not certain.

You may find  the following paper though Its not  on the taxonomy ,mentioning Nopalea dejecta.

Shaikh Mujaffar you have correctly identified the plant species. It is Nopalea dejecta (Syn. Opuntia dejecta) of family Cactaceae. This plant species is native of South America and by habit it is a shrub. In India generally it is cultivated as ornamental plant  in the gardens.

shaikh sir whatever photo you put here and identified its correct.it is a Nopalea dejecta.taxonomy of this plant is Plant I to 2 m. high, with a definite trunk, very spiny, the old areoles often bearing 6 or 8 spines,joints narrow, 10 to 15 cm. long, only moderately thick, often drooping, bright green even in age, bearing usually two somewhat spreading spines at an areole ; spines at first pale yellow or pinkish,

in age gray, the longest 4 cm. long; flower, including ovary and style, 5 cm. long; sepals obtuse; petals erect, dark red; stamens long-exserted, dark red. 

Reference

THE CACTACEAE

DESCRIPTIONS AND ILLUSTRATIONS OF

PLANTS OF THE CACTUS FAMILY

 BY

 N. L. BRITTON and J. N. ROSE

 Volume I

thanks

No question about the name: Nopalea dejecta.  It is common here, in cultivation and also wild.  As you all know, Mexico is the center of diversity of family Cactaceae and since I live in that country, Nopalea is a rather common sight.