Early Cretaceous angiosperm leaves from the Dakota Formation, Hoisington III locality, Kansas, USA Author Wang, Hongshan Author Dilcher, David L. text Palaeontologia Electronica 2018 34 A 2018-09-30 21 3 1 49 http://dx.doi.org/10.26879/841 journal article 10.26879/841 1094-8074 11062827 Rogersia dakotensis Wang and Dilcher, 2009 Figures 9.1, 9.3 , 10.1 FIGURE 7. Pabiania variloba Upchurch and Dilcher, 1990 . 1-3 , UF15706-24423, specimen showing suprabasal actinodromous primary venation (scale bar equals 1 cm) ( 1 ), enlargement of a sinus area to show sinus bracing by secondary veins (scale bar equals 2 mm) ( 2 ); and enlargement of basal portion of leaf to show two pairs of basal secondary veins (scale bar equals 2 mm) ( 3 ). 4-5 , UF15706-30154, specimen showing a long petiole and ocrea-like structure at the base (scale bar equals 5 mm) ( 4 ) and enlargement of the petiole to show the ocrea-like structure (scale bar equals 2 mm) ( 5 ). 6 , UF15706-14832, specimen showing suprabasal actinodromous primary venation and acute apices of the lobes. Scale bar equals 1 cm. FIGURE 8. Pabiania variloba Upchurch and Dilcher, 1990 . 1 , UF15706-14823, leaf showing basal actinodromous primary venation and basal secondary veins. Scale bar equals 1 cm. 2 , UF15706-24464, leaf showing rounded lobe apex. Scale bar equals 1 cm. 3 , UF15706-24587, specimen showing a small lobe on the left and entire margin on the right of the leaf. Scale bar equals 5 mm. 4 , Enlargement of Figure 8.2 to show straight primary vein extending to lobe apex and two series of loops in the excostal region. Scale bar equals 1 mm. FIGURE 9. 1 and 3 , Rogersia dakotensis Wang and Dilcher, 2009 , UF15706-24798, general leaf shape, note thin secondary veins forming intramarginal veins (scale bar equals 5 mm) ( 1 ) and enlargement to show intramarginal veins formed by looping secondary veins (scale bar equals 1 mm) ( 3 ). 2 and 4 , Rogersia parlatorii Dilcher and Wang, 2006 , UF15706-7529, specimen showing leaf shape (scale bar equals 5 mm) ( 2 ) and enlargement to show secondary venation (scale bar equals 5 mm) ( 4 ). Description. Leaf simple; whole lamina and base symmetrical; form linear oblong, L / W >9, 7.5 cm to 9 cm long and 0.5 cm to 1 cm wide. Apex attenuate. Base acute, decurrent. Margin entire. Petiole short, stout. Primary venation pinnate; primary vein stout, multi-stranded; course straight or slightly curved. Secondary venation brochidodromous; secondary veins thin relative to primary vein; subopposite, decurrent on primary vein; angle of divergence narrow acute (ca. 30º), spacing irregular; secondary veins uniformly curved to join exmedial branches of superadjacent secondary veins or superadjacent secondary veins at a distance of one fifth to one fourth of half lamina to form an intercostal region with its long axis oblique primary vein (ca. 30º), then continuing to join exmedial branches of adjacent secondary veins to form two series of loops; these loops enclosing elongate areas with long axis almost parallel to leaf margin; secondary veins running along the margin appearing to be intramarginal veins. Intersecondary veins present, one per intercostal region, simple, extending about one half of the distance from primary vein to leaf margin and then intersect with superadjacent secondary veins. Tertiary veins thin, irregular, percurrent with retroflexed or straight course. Veins of higher order not observed. FIGURE 10. 1 , Rogersia dakotensis Wang and Dilcher, 2009 , UF15706-24620, general leaf shape. Note short petiole. Scale bar equals 5 mm. 2-3 , Wolfiophyllum pfaffianum (Heer) Wang and Dilcher, 2009 , UF15706-14815, basal and middle portion of leaf, note strong primary vein and entire margin (scale bar equals 1 cm) ( 2 ) and enlargement of Figure 10.2 (area indicated by arrow) to show eucamptodromous venation, note intersecondary veins (Scale bar equals 1 mm) ( 3 ). Number of specimens examined. 200. Occurrences. Hoisington III locality, Kansas and Courtland I locality, Minnesota . Specimens illustrated. UF 15706-24798 ( Figure 9.1, 9.3 ); UF 15706-24620 ( Figure 10.1 ). Remarks. Rogersia dakotensis is similar in leaf shape and angle of divergence of secondary veins to Wolfiophyllum heigii from the Braun’s Ranch locality of Kansas , but they differ in that W. heigii has eucamptodromous secondary venation, forking secondary veins near margin, and percurrent or exmedially ramified tertiary veins ( Table 2 ).