One of endangered species of Indian medicinal plants is that of

Podophyllum hexandrum (the Himalayan mayapple) is a medicinal herb of the Himalayas.
Its rhizome yields the resin podophyllin, used to remove benign growths such as certain kinds of warts and as the source of anti-cancer drugs.
Because of over-collection from the wild it has become one of the endangered species of Indian medicinal plants.
Ocimum (tulsi) and garlic are medicinal plants that are widely cultivated and are not endangered.
Nepenthes (the pitcher plant) is an endangered plant, but it is an insectivorous plant and not a medicinal plant.
So the endangered Indian medicinal plant is Podophyllum.