Shrublike plants with stems up to ca. 5 cm and profuse adventitious rooting from nodal regions. Needle-like leaves at base of branches wiht spatulate leaves up to ca. 3 cm wide distally on some branches, needle-like leaves only on others. Phyllotaxis approaching 3/8, 5/13, and 8/21, with traces diverging from pith as single bundle in smaller stems and as double bundle in largest stems. Adventitious root traces not attached to primary xylem of stem or leaf, diverging at nodes distal to leaf trace and proximal to branche trace emission. Leaves hypostomatic with single rows of stomata. Leaf traces collateral, surrounded by distinct sheath and separated by compact, undifferentiated mesophyll. Leaf sclerenchyma of longitudinally oriente columns typically separated by two bundles; hypodermal sclerenchyma absent distal to leaf base. Cones irregularly arranged on both apical and proximal stem regions; xylem of cone axis often not continuous with xylem of stem. Pollen cones with five sporangia per cone scale, Florinites-type pollen 47-66 µm in greatest dimension.
Cordaixylon dumusum n. sp.
nomenclatorial act:
protologue/first publication
Page:
277
diagnosis:
systematic position:
Cordaitales, Cordaixylon Grand'Eury emend. Rothwell & Warner, 1984
typeseries:
Holotype. — Branching stem with attached leaves, bud, pollen cone, and immature cone, in C.B. 1604B bot — Bot, slide nos. 5489, 5490, 5503, 5522, 5524-5530, 5532, 5536, and 5557-5604 in the Paleobotanical Herbarium, Ohio University, figures 8, 9, 24 and 28.
Paratypes. — Branching stem with attached leaves and roots, in C.B. 1301A Bot — C Top, figures 3, 5, 15, 21, 23, 25, and 26; and fertile apex with attached leaves and immature cones, in C. B. 1397D Bot — E Top, not figured. Slide nos. of the paratypes are 5485, 5494, 5500, 5502, 5605 - 5615 and 5539-5545, 5616-5645, respectively, in the Paleobotanical Herbarium, Ohio University
stratigraphy:
Classification:
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