Calamophyton

The genus was established in 1926 from specimens collected by R. Kräusel & H. Weyland, in Hardberg and Kirberg, Rhineland, Germany, who identified the type species Calamophyton primaevum. A second species, C. renieri, was described by Suzanne Leclercq in Belgium in 1940; a third, C. bicephalum, also found in Belgium, by Leclercq and H. Andrews in 1960; and a fourth, C. forbesii, in the Mapleton Sandstone, Maine, United States, by James M. Schopf in 1964. It has since been suggested that C. primaevum and C. bicephalum are conspecific. All specimens date to the Middle Devonian, some 385 to 395 million years ago. The genus has been described as having an unusual—and unusually complex—morphology, superficially palm-like. Specimens are between 0.8 metres (2+1⁄2 feet) and 4 metres (13 ft) in height. Like other cladoxylopsids, the tree trunk was hollow, and composed of multiple interconnected longitudinal strands of vascular woody material (xylem). As the xylem bundles grew in diameter, they would split apart from one another near the apex of the trunk, thus limiting the overall height.