Final answer:
The fossil lycophyte that was a large tree in the Carboniferous and now makes up a large percentage of coal deposits is the Lycopodiales or club mosses. A feature that occurs on their bark is the presence of scale-like leaves called microphylls.
Step-by-step explanation:
The fossil lycophyte that was a large tree in the Carboniferous and now makes up a large percentage of coal deposits is the Lycopodiales or club mosses. These plants dominated the landscape of the Carboniferous period, growing into tall trees and forming large swamp forests. A feature that occurs on their bark is the presence of scale-like leaves called microphylls.
The two orders in the Lycopodiophyta are Isoetales or quillworts and Selaginellales or spike mosses. These orders are part of the same phylum as the club mosses and also consist of seedless vascular plants.