They had a central trunk, from the top of which several lateral branches were attached. Fossils of these plants originate in the Middle Devonian to Early Carboniferous periods (around ), mostly just as stems.
Cladoxylopsida contains two orders. The order Hyeniales is now included in Pseudosporochnales.
A recent (2017) discovery in Xinjiang in China of early Late Devonian (Frasnian, ca. 374 Ma) silicified fossil cladoxylopsid tree trunks (diameter up to c.70 cm) with preserved cellular anatomy showed an internal arrangement with many xylem bundles in the outer part and none in the interior; each bundle was surrounded by its own cambium layer, by which the tree's trunk widened.
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Media related to Cladoxylopsida at Wikimedia Commons