Dordrechtitaceae And. & And. 2003
As for the order Dordrechtitales
As for the order Dordrechtitales
Putative pinopsids bearing elongate cones of numerous subopposite, subdecussate fascicles of 3 (?4) T-shaped ovuliverous scales (bracts absent or fully fused) attached to short pedicels.
Pinopsid plants bearing ovate cones with helically arranged megasporophyll units comprising a single, large, triangular, free bract, and single, sessile, orthotropous, fully enclosed ovules
Dicranophyllalean plants with ovulate sporophylls attached singly to the leaf axil; ovules borne subapically on pinnate arms of sporophylls. foliage: Leaves fork twice or three times. Stem: With no leaf cushions.
Tubivascular linearicostate gymnospermous Cresscaffines, or synorhizous exogenæ, with naked seeds, two or more cotyledons, linearicostate leaves, and glanduliferous wood
Voltzialean plants with ovulate pre-cones comprising a compound cone-like zone of axillary dwarf shoots between proximal and distal 'vegetative zones'; ovuliferous dwarf shoots bilateral, with a zone of several sterile scales subtending a fan of 3 to 4 uniovulate sporophylls; ovules inverted.
Leafy shoots bearing helically arranged, long and linear (up to 3 cm) or shorter and spathulate leaves with a thick cuticle. Leaf length and angle of attachment vary greatly along length of shoot. Leaves 2.0-2.5 mm wide. Leaf margin smooth or with vestigial cuticular microdenticulation. Stomatiferous furrows deep and narrow, their lateral walls strongly cutinized and papillose, stomatal band up to 250 µm wide, located on bottom wall. Stomatal pit bounded by cutin ring and overhung by long papillae arising from subsidiary cells. Epidermal cells up to 25 µm wide and up to 35 µm long.
Simple linear leaves with two marginal veins. The leaves are up to 60 mm long in available fragments and 1.5-2.5 mm wide. The furrows are 0.4 mm wide, and the distance between teh furrow and the margin is 0.3-0.4 mm.
Isolated leaves and leafy shoots. Leaves helically arranged, linear of spathulate, apex obtuse or acute, base decurrent. Lower surface of leaf with one stomatiferous furrow running along each lateral margin. Epidermal cells of lateral walls of furrows papillose; subsidiary cells also bearing papillae which overhang stomatal it. Leaf margin occasionally bearing cuticular microdenticulation. Axillary buds enveloped by cataphylls.