Clevelandodendron ohioensis, Gen. et sp. nov., A Slender Upright Lycopsid from the Late Devonian Cleveland Shale of Ohio

Growth habit of the late Paleozoic rhizomorphic tree‐lycopsid family Diaphorodendraceae: Phylogenetic, evolutionary, and paleoecological significance

“…Unsurprisingly, these independently evolved trees share a morphology that appears unintuitive to the neobotanical eye. Isoetaleans are characterized by distinctive “stigmarian” rooting organs, best termed rhizomorphs (Rothwell, 1984; Bateman et al, 1992; DiMichele and Bateman, 1996a; Pigg, 2001)—organs homologous with the lobed or cormose bases of the more typically isoetoid group(s), which also were prominent in Paleozoic landscapes (DiMichele et al, 1979; Jennings et al, 1983; Pigg and Rothwell, 1983; Bateman and DiMichele, 1991; Bateman, 1992, 1994; Chitaley and Pigg, 1996; Cressler and Pfefferkorn, 2005). In addition, the strongly determinate, modular (arguably herb‐like) growth of the rhizomorphic lycopsids has long made them a favored subject of ontogenetic inference among paleobotanists (e.g., Eggert, 1961; Rothwell, 1984; Bateman, 1992, 1994; Sanders et al, 2011).…”

A new Late Devonian isoetalean lycopsid from New South Wales, Australia: Cymastrobus irvingii gen. et sp. nov

“…The stem is terminated by a 9 cm long, 6 cm wide bisporangiate cone comparable in size and shape to the Barraba specimen (Chitaley and Pigg, 1996). Because of the superficial resemblance between these two contemporaneous cones, it could be tempting to hypothesize a similar growth habit for the plants that produced them.…”

“…Wang et al (2003) proposed that Jurinodendron, together with Clevelandodendron ohioensis (Chitaley and Pigg, 1996) and Bisporangiotrobus harrisii (Chitaley and McGregor, 1988) represent the basal taxa of a supposedly monophyletic group that they referred to as the "Isoetales sensu stricto." This group would encompass the isoetalean lycopsids characterized by cormose rather than stigmarian rhizomorphs.…”

“…It superficially resembles the cone of Clevelandodendron, a contemporaneous plant of limited height characterized by an unbranched habit and a cormose base. When all characters are considered, however, the closest taxon is another contemporaneous genus, Bisporangiostrobus, represented by branched stems thought to belong to an arborescent rhizomorphic lycopsid related to Jurinodendron (Chitaley and Pigg, 1996).…”

Plant Paleoecology in Deep Time1

“…from the Triassic, was reconstructed from a complete plant, a finding made perhaps more likely because of the small stature of the plant (Rothwell et al, 2000). Some other whole plants found in the fossil record include the isoetalean lycopsids Clevelandodendron Chitaley & Pigg (1996), of Late Devonian age, and Chaloneria Pigg & Rothwell (1983) and Hartsellea Gastaldo, Gibson & Blanton-Hooks (2006) of Pennsylvanian age, all with pole-like growth forms and comose base. The former is a single specimen terminating in a fertile zone, whereas Chaloneria was put together from a number of variably complete specimens, terminating either in a fertile zone or with intercalated fertile and sterile zones.…”