Question

Name the extinct plant which is devoid of true roots and leaves

Answer 1

I think you are talking about air plants botanically called epiphytes especially known as terrestrial epiphytes. The best-known epiphytic plants include mosses, orchids, and bromeliads such as Spanish moss (of the genus Tillandsia), but epiphytes may be found in every major group of the plant kingdom. They take their nourishment from the air. Some have roots but they are used for anchorage not to derive nourishment. All the one I can think of have stems and leaves.
here is your answer ☺️

Answer 2

Bryophyte extinct plants