Wolfiophyllum pfaffianum (Heer) Wang and Dilcher, 2009

Wang, Hongshan & Dilcher, David L., 2018, Early Cretaceous angiosperm leaves from the Dakota Formation, Hoisington III locality, Kansas, USA, Palaeontologia Electronica (34 A) 21 (3), pp. 1-49 : 17-18

Wolfiophyllum pfaffianum (Heer) Wang and Dilcher, 2009

Figure 10.2-3

Description. Leaf simple; whole lamina and base symmetrical; form very narrow elliptic to narrow oblong, L / W 4 to>7, 10 cm to 12 cm long (estimated maximum length) and 1.3 cm to 2.6 cm wide. Apex missing. Base acute, decurrent. Margin entire. Petiole normal, short, stout, up to 1 cm long and 1.5 mm wide, with decurrent lamina tissue on both sides, curved to one side. Primary venation pinnate; primary vein stout, multi-stranded, course straight or slightly curved. Secondary venation eucamptodromous, secondary veins upturned and gradually diminishing apically near the margin, connected to the superadjacent secondary veins by a series of cross veins without forming prominent marginal loops; secondary veins up to 12 pairs per lamina; angle of divergence uniform, narrow acute (less than 45 °); secondary veins uniformly curved and gradually diminishing apically inside the margin, connected to the superadjacent secondary veins without forming prominent loops; secondary vein course apically curved, occasionally forking near the margin; intersecondary veins common, one per intercostal region, extending half to almost the same distance as adjacent secondary veins; intersecondary veins simple. Tertiary veins predominately percurrent, course straight; angle of origin AO (acute on lower side of secondary veins and obtuse on upper side of secondary veins), forming cross veins between adjacent secondary and intersecondary veins. Veins of higher order poorly preserved.

Number of specimens examined. 1.

Specimens illustrated. UF 15706-14815 ( Figure 10.2-3 ).

Occurrences. Hoisington III locality, Kansas and Courtland I locality, Minnesota .

Remarks. The suite of characters, especially the combination of narrow elliptic simple leaf and eucamptodromous venation is different from any other angiosperm leaf megafossils from the Hoisington III locality, Kansas. The distinction between Wolfiophyllum pfaffianum with other similar leaves from the Dakota Formation is presented in Table 2 .

Figures

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).