1. A member of an ancient group of vascular plants that flourished during the Paleozoic era, characterized by small leaves and simple branching patterns; includes modern club mosses.
Usage: botanical; paleontology

Examples

• Lycopsids were among the first plants to develop vascular tissue for transporting water and nutrients.
• During the Carboniferous period, lycopsids grew to enormous sizes, forming vast swamp forests.
• Modern club mosses are the surviving descendants of the lycopsids that dominated ancient landscapes.
• Paleontologists study fossilized lycopsids to understand early plant evolution.
• The simple leaf structure of lycopsids differs significantly from that of ferns and seed plants.